ABDOMINAL WALL Uitnodiging

Voor het bijwonen van de openbare verdediging van ABDOMINAL mijn proefschrift getiteld

Improving surgical care Abdominal Wall Hernia WALL Improving surgical care

Op vrijdag 26 september 2014 om 13.45 uur in de Aula van de Vrije Universiteit. HERNIA De Boelelaan 1105, 1081 HV in Amsterdam. Improving surgical care Receptie na afloop ter plaatse

Promovenda: Marijn Poelman Gerard Brandtstraat 3-4 1054JH Amsterdam 0641013388 [email protected]

Paranimfen: Maartje Poelman [email protected] Yvonne Bors [email protected] Marijn Poelman De pdf van het proefschrift is te downloaden op: Marijn Poelman www.inchtrial.nl ABDOMINAL WALL HERNIA

Improving surgical care

Marijn Poelman Title: ABDOMINAL WALL HERNIA, improving surgical care Dissertation, Vrije Universiteit, Amsterdam, the Netherlands

ISBN 978-94-6108-706-5

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The printing of this thesis was financially supported by: ABN AMRO/ Chipsoft/ Covidien/ ChirurgenNoordWest.nl/ Dutch Hernia Society/ Foreest instituut Alkmaar/ Vrije Universiteit Amsterdam/ Bard Nederland/ Olympus Nederland BV/ Nederlandse Vereniging voor Endoscopische Chirurgie/ Nederlandse Vereniging voor Gastroenterologie

Copyright © M. Poelman, 2014. All rights reserved. No part of this publication may be reproduced. VRIJE UNIVERSITEIT

ABDOMINAL WALL HERNIA

Improving surgical care

ACADEMISCH PROEFSCHRIFT

ter verkrijging van de graad Doctor aan de Vrije Universiteit Amsterdam, op gezag van de rector magnificus prof.dr. F.A. van der Duyn Schouten, in het openbaar te verdedigen ten overstaan van de promotiecommissie van de Faculteit der Geneeskunde op vrijdag 26 september 2014 om 13.45 uur in de aula van de universiteit, De Boelelaan 1105

door

Marie Marijn Poelman

geboren te Groningen promotor: prof.dr. H.J. Bonjer copromotor: dr. W.H. Schreurs Promotiecommissie

Overige leden: prof.dr. M.A. Cuesta, VUMC Amsterdam, Nederland prof.dr. J. Jeekel, Erasmus MC, Rotterdam prof.dr. H. Van Goor, Radboudumc, Nijmegen prof.dr. G. Kazemier, VUMC Amsterdam prof.dr. J. Lange, Erasmus MC Rotterdam dr. B.J. Dwars, Slotervaartziekenhuis Amsterdam drs. B.L.A.M. Langenhorst, Medisch Centrum Alkmaar

Contents

Chapter 1 General introduction and outline of this thesis 9

Part 1 Incisional hernia

Chapter 2 Modified onlay technique for the repair of the more complicated 21 incisional : single-centre evaluation of a large cohort. Hernia. 2010 Aug;14(4):369-74.

Chapter 3 Health-related quality of life in patients treated for incisional hernia 33 with an onlay technique. Hernia. 2010 Jun;14(3):237-42.

Chapter 4 Open abdomen treatment: planned ventral hernia or delayed fascial 45 closure? A review of the literature compared with daily practice. Submitted.

Chapter 5 The INCH-trial: A multicenter randomized controlled trial comparing 57 the cost-effectiveness of conventional open surgery and laparoscopic surgery for incisional . BMC Surgery 2013 13:18 (7 June 2013).

Chapter 6 Comparison of the Dutch and English version of the Carolinas Comfort 69 Scale; a specific quality of life-questionnaire for abdominal hernia repairs with mesh. Hernia 2013 Oct 29.

Chapter 7 Laparoscopic incisional hernia repair: Influence of surgical technique on 85 recurrence rate. A systematic review of the literature. Submitted. Part 2 Groin hernia

Chapter 8 EAES Consensus Development Conference on endoscopic repair of 103 groin hernias. Surg Endosc. 2013 Oct;27(10):3505-19.

Chapter 9 Summary and Discussion 133

Chapter 10 Nederlandse samenvatting 145 Dankwoord 149 Curriculum Vitae 155 Chapter 1

General introduction and outline of this thesis R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

10 | Chapter 1 The abdominal wall R1 The abdominal wall serves many functions such as stabilization and movements of the trunk, 1 R2 containment of the viscera and respiration. Adaptation of the abdominal wall to accommodate R3 R4 increasing intra-abdominal volume due pregnancy, obesity or is another distinct feature of R5 the abdominal wall. The strength of the abdominal muscles decreases with age due to reduced R6 activity and degeneration. Decrease of muscle volume and tone results in enlargement of pre- R7 existent hernias of the abdominal wall. The groin, the umbilicus and the hiatus of the diaphragm R8 are sites of predilection for hernia formation. Incomplete fusion of tissues during embryologic R9 development causes epigastric, above the umbilicus, or hypogastric, below the umbilicus, R10 hernias. The intersections of the different layers of the abdominal wall muscles predispose to the R11 development of rare hernias such as Petit and Grynfeltt hernias. Groin hernias, particularly those R12 cranially to the iliopubic ligament are the most common hernias. Annually, more than 25,000 R13 patients with inguinal hernias undergo surgical repairs in the Netherlands. R14 R15 These congenital hernias, hernias due to ageing together with hernias arising due to impaired R16 healing of incisions of the abdominal wall, i.e. incisional hernias, constitue the entire spectrum of R17 hernias of the abdominal wall. The optimal management of abdominal wall hernias has remained R18 R19 unresolved despite the fact that the first hernia repairs occurred more than two centuries ago. R20 R21 Incisional hernias R22 Incisional hernias are defects of the fascia of the abdominal wall, which can only develop after R23 . Bulging of abdominal contents through the scar is visible and palpable when R24 patients are standing or coughing. These hernias occur in at least 10-15% of patients within R25 10 years after open abdominal surgery (1). Incisional hernias may be asymptomatic, but are R26 frequently associated with pain or discomfort. Strangulation of herniated bowel is the most R27 concerning consequence of an incisional hernia. Incisional hernias affect the quality of life and R28 economic productivity of patients (2). R29 Pre-disposing factors for developing an incisional hernia are obesity and post-operative surgical R30 site infections (3). The pathogenesis of incisional hernias is multifactorial. Altered collagen R31 metabolism and extra-cellular matrix disorders are important contributory factors (4). R32 When considering the ingenious design of the abdominal wall, one would suppose that repair R33 R34 of abdominal wall hernias is complicated. Nevertheless, abdominal wall surgery is generally not R35 considered very challenging. R36 R37 R38 R39

General introduction and outline of this thesis | 11 R1 Incisional hernia repair R2 Over 100,000 are performed annually in the Netherlands, more than 10,000 of these R3 patients will develop an incisional hernia. Eighty percent of all patients with an incisional hernia R4 undergo surgical repair (5). The natural course of an incisional hernia is unknown. It is unclear R5 whether surgery should be recommended to asymptomatic patients to prevent obstruction or R6 strangulation of the bowel. Thirty-three to seventy-eight percent of the patient with an incisional R7 hernia are reported to become symptomatic over time (6,7). The only way to resolve this disease R8 R9 is to repair the hernia surgically. R10 R11 The aim of an incisional hernia repair is to reestablish the function of the abdominal wall; the R12 barrier between viscera and the external environment, the muscular function and the cosmesis of R13 the abdominal wall should be restored. Before the introduction of synthetic meshes to reinforce R14 the abdominal wall, repairs of incisional hernias were done by primary suture repairs. Recurrence R15 rates of suture repairs, particularly in larger defects, were high at long-term follow up. With R16 the introduction of prosthetic meshes at the end of the nineteenth century, recurrence rates R17 significantly dropped below 15% (8). However, the perfect solution for restoring all abdominal R18 wall functions has not yet been found. Because “mesh repair” is the best available surgical R19 technique so far, it is considered the gold standard. However, the surgical procedure to perform R20 this “mesh repair” is far from standardized. R21 R22 A wide array of prosthetic meshes is available for incisional hernia repair. Most of these meshes R23 R24 are comparable in terms of adhesion formation and incorporation into the abdominal wall R25 and do not differ in clinically significant outcomes such as post-operative complication rates or R26 recurrences (9,10). R27 R28 Uniform indications for laparoscopic or open incisional hernia repair have not been determined. R29 Several randomized controlled trials, reviews and meta-analysis have shown that laparoscopic R30 incisional hernia repair is safe and is associated with a shorter hospital stay and fewer wound R31 infections (11-14). Recurrences rates, chronic pain and quality of life after open and laparoscopic R32 incisional hernia repair are similar (1,12,15). Patients with large abdominal wall defects appear R33 to benefit from reconstruction of the midline, which is usually done in open repair, in order to R34 restore the functionality of the abdominal wall (16). The fear for intra-abdominal adhesions due R35 to former (complicated) surgeries might direct the surgeon to choose an open repair. It remains R36 unclear whether the cost-effectiveness of the laparoscopic repair is superior to open surgery (12- R37 14). R38 R39

12 | Chapter 1 Proper evaluation of outcomes of incisional hernia repair requires clear definition of size and R1 location of these hernias. The European Hernia Society (EHS) categorized incisional hernias 1 R2 to facilitate scientific incisional hernia research (17). A classification system of abdominal wall R3 R4 hernias has been formulated. The classification of incisional hernias might help in and defining R5 the optimal treatment approach per subgroup. R6 R7 Traditional open repair involves repair of the hernia employing the scar of the previous surgery. A R8 preperitoneal, sublay or onlay mesh repair (picture 1), sometimes combined with an augmentation R9 of the abdominal wall through component separation technique can be performed. The mesh is R10 held in position between the muscular layers of the abdominal wall, usually in combination with R11 sutures. R12 The morbidity of open incisional hernia repair varying from respiratory infections, severe chronic R13 pain, recurrences to wound and mesh infections occur in 15 percent of patients. The position of R14 the mesh whether onlay, inlay or sublay does not affect the morbidity rate (2). R15 Component separation technique is a procedure based on enlargement of the abdominal wall by R16 separating the muscular layers in order to close the abdomen tension-free. The amount of soft R17 tissue dissection that needs to be done in the abdominal wall is considerable, leading to wound R18 R19 related complications in up to 50% of the cases (18). The component separation technique R20 without the use of a mesh should only be used when contents of the gut are present in the R21 abdominal cavity due to perforation of the gut, because bacteria will lodge on the mesh resulting R22 in chronic infection. R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 Picture 1. R39

General introduction and outline of this thesis | 13 R1 With the growing interest of general surgeons in , which started in the late 1980s, R2 surgeons started to perform laparoscopic incisional hernia repairs (19). The laparoscopic repair R3 entails employment of mesh that is placed intraperitoneally covering the fascial defect while R4 leaving the hernia sac in place. The mesh is fixed to the abdominal wall with transfascial sutures R5 and/or with the use of tackers (picture 2). In general, the fascial edges are not brought together R6 in the laparoscopic repair although some early experiences of laparoscopic closure of the midline R7 have been reported. R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21

R22 Picture 2. R23 R24 R25 Repair of incisional hernias is associated with considerable morbidity for the patient as well R26 with costs due to the surgical procedure and loss of economic productivity. A reduction of the R27 complication rate of incisional hernia surgery may lead to earlier recovery, which in turn shortens R28 hospital stay and promotes a faster return to work. Optimizing and standardizing the surgical R29 treatment of patients with an incisional hernia potentially saves our patients morbidity, and could R30 save our society millions of euros. R31 R32 Central questions and outline of this thesis R33 The main question of this thesis is: R34 Is it possible to determine the optimal management of incisional abdominal and groin hernias R35 through clinical evaluation, literature research and assessment by experts throughout Europe? R36 R37 R38 R39

14 | Chapter 1 In the first two chapters, the open onlay mesh technique for the repair of large incisional R1 hernias was evaluated. Other open techniques, such as the component separations technique, 1 R2 are accepted for the repair of large incisional hernias. These techniques are invasive and some R3 R4 require entering the abdominal cavity. The modified onlay technique was used to repair the more R5 complicated abdominal wall defects, i.e. after open-abdomen treatment or fascial necrosis. A R6 retrospective analysis of these patients was performed to analyze whether this is an appropriate R7 technique for the repair of large incisional hernias (chapter 2). The next step was to examine the R8 quality of life of these patients after surgery (chapter 3). R9 R10 Patients with an open abdomen develop a specific form of incisional hernia when there is no R11 delayed fascial closure. A standard approach to the management of an open abdomen is absent. R12 Patients who were treated with an open abdomen at a university hospital and a large teaching R13 hospital were selected and evaluated (chapter 4). A review of the literature was performed R14 to record the outcomes of various methods of fascial closure and correlate these with the R15 development of an incisional hernia. R16 R17

A large clinical trial randomizing patients with incisional hernias either for open or laparoscopic R18 R19 repair, called the “INCH trial” was started. The aim of this trial is to examine if laparoscopic R20 incisional hernia repair is superior to open incisional hernia repair in terms of hospital stay and R21 return to normal activities. Patients with an incisional hernia suitable for laparoscopic repair are R22 randomized to either laparoscopic or open repair. Alongside the trial, all the patients with an R23 incisional hernia who do not want to participate, whose hernia is considered to be unsuitable R24 for laparoscopic repair and the patients who are treated conservatively will be registered in a R25 prospective database. The preparations of the INCH trial started in 2010 and a study protocol R26 was written (chapter 7). Funding was gained through national and European societies. Ethical R27 approval was obtained and the trial started in July 2012 and is still running. R28 R29 Two studies were initiated in preparation of the start of the INCH trial. A review was performed R30 to determine the influence of surgical technique (overlap, use of transfascial sutures and type of R31 mesh) on the recurrence rate in laparoscopic incisional hernia repair (chapter 6). R32 The Carolina Comfort Scale, a disease specific questionnaire to measure quality of life that has R33 R34 been validated in English, was validated in Dutch in order to use this questionnaire in the INCH R35 trial (chapter 5). R36 R37 R38 R39

General introduction and outline of this thesis | 15 R1 While initiating the INCH trial, the Consensus Development Conference on endoscopic groin R2 hernia repair was organized for the European Association of Endoscopic Surgeons (chapter 9). R3 The aim was to provide practical guidelines employing available medical evidence combined with R4 the opinions of an expert panel and the membership of the EAES. R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

16 | Chapter 1 References R1 R2 1. Cassar K, Munro A. Surgical treatment of incisional hernia. Br J Surg 2002, May;89(5):534-45. 1 R3 2. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. Open surgical procedures for incisional hernias. R4 Cochrane Database Syst Rev 2008(3):CD006438. R5 3. Llaguna OH, Avgerinos DV, Lugo JZ, Matatov T, Abbadessa B, Martz JE, Leitman IM. Incidence and risk factors for the development of incisional hernia following elective laparoscopic versus open colon R6 resections. Am J Surg 2010, Aug;200(2):265-9. R7 4. Rosch R, Junge K, Knops M, Lynen P, Klinge U, Schumpelick V. Analysis of collagen-interacting proteins R8 in patients with incisional hernias. Langenbecks Arch Surg 2003, Feb;387(11-12):427-32. R9 5. Nieuwenhuizen J, Kleinrensink GJ, Hop WC, Jeekel J, Lange JF. Indications for incisional hernia repair: An international questionnaire among hernia surgeons. Hernia 2008, Jun;12(3):223-5. R10 6. Courtney CA, Lee AC, Wilson C, O’Dwyer PJ. Ventral hernia repair: A study of current practice. Hernia R11 2003, Mar;7(1):44-6. R12 7. Vardanian AJ, Farmer DG, Ghobrial RM, Busuttil RW, Hiatt JR. Incisional hernia after transplantation. J Am Coll Surg 2006, Oct;203(4):421-5. R13 8. Luijendijk RW, Hop WC, van den Tol MP, de Lange DC, Braaksma MM, IJzermans JN, et al. A comparison R14 of suture repair with mesh repair for incisional hernia. N Engl J Med 2000, Aug 10;343(6):392-8. R15 9. Eriksen JR, Gögenur I, Rosenberg J. Choice of mesh for laparoscopic ventral hernia repair. Hernia 2007, R16 Dec;11(6):481-92. R17 10. Colon MJ, Telem DA, Chin E, Weber K, Divino CM, Nguyen SQ. Polyester composite versus PTFE in laparoscopic ventral hernia repair. JSLS 2011;15(3):305-8. R18 11. Olmi S, Scaini A, Cesana GC, Erba L, Croce E. Laparoscopic versus open incisional hernia repair: An R19 open randomized controlled study. Surg Endosc 2007, Apr;21(4):555-9. R20 12. Sauerland S, Walgenbach M, Habermalz B, Seiler CM, Miserez M. Laparoscopic versus open surgical R21 techniques for ventral or incisional hernia repair. Cochrane Database Syst Rev 2011(3):CD007781. R22 13. Forbes SS, Eskicioglu C, McLeod RS, Okrainec A. Meta-analysis of randomized controlled trials comparing open and laparoscopic ventral and incisional hernia repair with mesh. Br J Surg 2009, R23 Aug;96(8):851-8. R24 14. Sajid MS, Bokhari SA, Mallick AS, Cheek E, Baig MK. Laparoscopic versus open repair of incisional/ R25 ventral hernia: A meta-analysis. Am J Surg 2009, Jan;197(1):64-72. R26 15. Itani KM, Hur K, Kim LT, Anthony T, Berger DH, Reda D, et al. Comparison of laparoscopic and open repair with mesh for the treatment of ventral incisional hernia: A randomized trial. Arch Surg 2010, R27 Apr;145(4):322-8; discussion 328. R28 16. Eker HH, Hansson BM, Buunen M, Janssen IM, Pierik RE, Hop WC, et al. Laparoscopic vs. Open R29 incisional hernia repair: A randomized clinical trial. JAMA Surg 2013, Mar;148(3):259-63. R30 17. Muysoms FE, Miserez M, Berrevoet F, Campanelli G, Champault GG, Chelala E, et al. Classification of primary and incisional abdominal wall hernias. Hernia 2009, Aug;13(4):407-14. R31 18. de Vries Reilingh TS, van Goor H, Rosman C, Bemelmans MH, de Jong D, van Nieuwenhoven EJ, et al. R32 “Components separation technique” for the repair of large abdominal wall hernias. J Am Coll Surg R33 2003, Jan;196(1):32-7. 19. LeBlanc KA, Booth WV. Laparoscopic repair of incisional abdominal hernias using expanded R34 polytetrafluoroethylene: Preliminary findings. Surg Laparosc Endosc 1993, Feb;3(1):39-41. R35 R36 R37 R38 R39

General introduction and outline of this thesis | 17

PART I

Incisional hernias

Chapter 2

Modified onlay technique for the repair of the more complicated incisional hernias:

Single centre evaluation of a large cohort

Poelman MM Langenhorst BL Schellekens JF Schreurs WH

Hernia. 2010 Aug;14(4):369-74. R1 Abstract R2

R3 Background The repair of incisional hernias remains a challenge for the general surgeon. R4 Indications for surgery are severe bowel obstruction, as well as aesthetic problems. There are R5 various surgical methods to correct these hernias with varying results. However, the gold standard R6 has not yet been found. Both laparoscopic repair and the component separation technique (CTS) R7 have proven to be acceptable techniques; however, they are not always suitable to resolve the R8 R9 more complicated abdominal wall defects, i.e. after open abdomen treatment or fascial necrosis. R10 In our hospital we developed a new onlay technique, which we have evaluated in the following R11 research. R12 R13 Patients & Methods During a period of 10 years (1996-2007) 101 patients with an incisional R14 hernia were corrected with the new onlay technique. A marlex mesh of dimensions at least 10x20 R15 cm was used, overlapping the fascia by at least 5cm at each side. This mesh was stapled onto the R16 fascia with skin staples. Of the 101 patient there were 45 men and 56 women, with a mean age R17 of 55 years. Nine patients died and 13 were lost during follow up. Of the remaining 79 patients, R18 eight refused to participate. The mean follow-up time was 64 months (normal distribution, SD R19 34 months). R20 This cohort of 101 patients was studied retrospectively. R21 R22 Results Seventy-one of the 101 patients were evaluated at our outpatient clinic. For 24 patients R23 R24 (25%) the operation was for a recurrence after an inscisional hernia correction in the past. R25 Twenty-one patients (20%) had an open abdomen treatment in their medical history. The surgical R26 procedure was technically possible in all patients and the mean operation time was 63 minutes. R27 The median admission time was 4,5 days (Quartiles 3-6,25). The mean follow-up time was 64 R28 months (SD 35 months). A seroma was reported in 27 of 101 patients (27%) and a wound R29 infection in 22 patients (21%) of which 7 patients had to be re-operated. Only if a patient was R30 evaluated at our outpatient clinic could reherniation have been scored; this occurred in 11 of 71 R31 patients (16%). R32

R33 Conclusion This technique is an effective and simple procedure to correct incisional hernias with R34 acceptable complication rates and is feasible even in the more complicated hernias. R35 R36 Key Words Incisional hernia, abdominal wall defects, mesh repair, hernia R37 R38 R39

22 | Chapter 2 Introduction R1 R2

Incisional hernias are a frequent complication after abdominal surgery, with an incidence of 10- R3 R4 23%(1;2). Although these hernias can be treated conservatively (with techniques like a bodice), R5 frequently, there are reasons to correct them surgically. Incisional hernias enlarge over time, cause R6 pain and/or aesthetic complaints. They can cause serious complications like bowel obstruction 2 R7 due to incarceration or strangulation. Patients suffer from these hernias and their quality of life R8 as well as their chances for employment are reduced (3). Improvement of the quality of life is the R9 major reason to seek surgical care (4-6). R10 R11 Incisional hernia surgery still is a challenge for the general surgeon. Repair of these hernias comes R12 with a high recurrence rate, high morbidity and, therefore high costs. Frequent complications are R13 reherniation, seroma formation and wound infection (7;8). Many techniques have been studied R14 but the gold standard has not yet been found (2;3;9). This is probably, at least partially, due to R15 the multifactorial aetiology of incisional hernias. Failures of the surgical technique, deterioration R16 of the patient’s nutritional status as well as interpersonal factors contribute. Reherniation rates R17 of 0-36% have been reported, even after mesh repair (3;7;8;10). There is no evidence that R18 R19 laparoscopic repair has a lower recurrence rate compared to open repair (11;12) and a recent R20 Cochrane analysis states that there is insufficient evidence as to which mesh position or which R21 type of mesh should be used (3). R22 Most challenging are, of course, the large and/or the complicated hernias. There is no superior R23 technique and the overall results in all series are, at best, moderate. In this article, we report a R24 new technique, an onlay mesh fixed with multiple skin staples. A single-centre R25 retrospective study was performed. R26 R27 R28 Methods R29 R30 Patients R31 All patients who had an incisional hernia operation between January 1996 and January 2007 R32 were selected. Out of this group the patients who were operated using an onlay polypropylene R33 R34 mesh, with a minimum size of 10x20 cm fixed with skin staples were included in this study. This R35 onlay-technique was only used when a large, complicated hernia was present. Smaller, simple R36 hernias were corrected using laparoscopy or open techniques. R37 R38 R39

Modified onlay technique for the repair of the more complicated incisional hernias | 23 R1 Surgical procedure R2 All operations are performed under . Patients are placed in the supine R3 position with their arms tucked in at the sides. After disinfection, one dosis of antibiotics was R4 given prior to the start of the operation (cefuroxim 1,500 mg iv). The skin scar was sometimes R5 excised and the subcutis opened. A de-epithelialisation was performed when the fascia was R6 absent and the subcutis was spread until the borders of the remaining fascia were found. A plane R7 of at least 5 cm was made in all directions over the fascia. The fascial edges were approximated R8 R9 as far as possible and closed using an absorbable vicryl suture, putting the de-epithelialized R10 part intra-abdominally without entering the abdominal cavity. After the hernia was successfully R11 approximated and haemostasis was achieved the Marlex mesh (Marlex©; C.R. Bard) was placed R12 on the freed fascial edges and trimmed to fit. The mesh was never put directly on the intestines. R13 Fascia, de-epithelialized tissue or omentum was always used to put in between the intestines and R14 the mesh. The mesh was fixed with over 150 skin staples to the fascia (figure 1). Two suction R15 drains were placed on top of the mesh and the subcutis and skin were closed in layers. R16 R17 Follow-up R18 All patients still alive were sent a letter to ask if they were willing to visit our outpatient clinic R19 for an evaluation. Patients who opted not to participate were asked for what reason. This was R20 then documented. After written consent was given, patients were invited to our outpatient clinic R21 for an interview and physical examination of their abdomen. A recurrent hernia was diagnosed R22 when a facial defect could be palpated when lifting the head from the examination table to raise R23 R24 the abdominal pressure. If this examination was not conclusive (in two patients) a computed R25 tomography (CT) scan was performed. R26 Demographics as well as pre-, peri- and postoperative data were collected. Patient history and R27 special features such as history of an open abdomen were noted. Post-operative outcomes were R28 wound-edge necrosis, wound infection, fistulas, seromas, bleedings, re-admission and length of R29 stay, re-operation, mortality and re-herniation in the follow-up. R30 R31 All of the data were entered into an SPSS database. All statistics mentioned are means or medians R32 along with their extremes or are in frequencies. R33 R34 R35 R36 R37 R38 R39

24 | Chapter 2 R1 R2 R3 R4 R5 2 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 Figure 1. R20 R21 R22 Results R23 R24 Patients R25 Between January 1996 and January 2007, 119 patients with incisional hernias were treated using R26 this onlay technique. The same two surgeons operated all of these patients, except six. These six R27 patients were excluded from this study because it was not certain that exactly the same technique R28 was used. In 12 patients, an attempt was made to correct the incisional hernia with the new R29 onlay technique, but failed due to iatrogenic bowel lesions. Eventually these hernias were not R30 corrected with a mesh. This group was also excluded. In total, 101 patients were included. R31 R32

Mean age at time of operation was 55 years (normal distribution, SD 14,4 years). There were R33 R34 45 (44%) males and 56 (56%) females. Nine of these patients had died at time of evaluation. R35 These deaths were not related to the hernia correction. Thirteen patients were lost to follow R36 up. Eight patients refused to participate, three of them because they were dissatisfied and five R37 because of logistic reasons. Therefore, it was possible to evaluate only 71 of the 101 patients in R38 R39

Modified onlay technique for the repair of the more complicated incisional hernias | 25 R1 our outpatient clinic. Seroma formation, infection and co morbidity is reported using the files of R2 all 101 patients. Recurrence was scored after the patients were seen in follow-up and is therefore R3 only mentioned in the outpatient group (n=71). R4 R5 Indications for surgery were complaints of bowel obstruction, i.e. patients felt pain or had difficulties R6 passing stool. Only a minority of the patients found the hernia aesthetically unacceptable. R7 R8 R9 The most prevalent comorbidity (table 1) is obesity (mean Body Mass Index [BMI] >29); 43 patients R10 had a BMI of more than 29. Nineteen patients had a history of cardiovascular disease. There were R11 11 diabetes, 27 patient smoked and 5 used corticosteroids. Seventy patients (70%) developed an R12 incisional hernia after a medial . About 18 patients had a recurrent hernia after former R13 incisional hernia repair using another technique. There were 21 patients (20%) with a history of R14 open abdomen treatment. R15

R16 Table 1: Baseline characteristics of patients R17 Baseline characteristics R18 N (%) mean SD minimum maximum R19 Gender 56 (55) female Diabetes 11 (11) R20 Cardiovascular disease 19 (19) R21 Pulmonary disease 18 (18) R22 Smokers 27 (27) R23 Use of corticosteroids 5 (5) History of open abdomen treatment 21 (20) R24 ASA-score* at time of operation 1,8 0,6 1 3 R25 BMI 29 9 19 48 R26 R27 R28 The surgical procedure was technically possible in all patients and the mean operation time was R29 63 minutes. The median admission time was 4,5 days (Quartiles 3-6,25). The mean follow-up R30 was 64 months (SD 34 months). During follow-up, 27 patients (27%) were seen more frequently R31 in the outpatient department because of a seroma. A wound infection was found in 22 patients R32 (21%). Seven of these patients had to be operated again: three with a seroma and a wound- R33 infection, two with only a seroma and two with only a wound infection. In the majority of cases, R34 the patient with seromas and infections could be treated without surgical interference. R35 About six patients (6%) suffered chronic pain and, in one case, the mesh had to be removed. R36 Whether or not this resolved the pain is unknown because the patient was lost for follow up. R37 Most patients report pain or an unpleasant sensation when bending over, due to stiffness of R38 R39

26 | Chapter 2 the mesh. None of them considered this invalidating. Migration of the mesh was not seen. Re- R1 herniation occurred in 11 patients (16%) (Table 2). R2 R3 R4 Table 2: Complications N (%) Surgical interference R5 Seroma 27 (27) 5 2 R6 Infection 22 (21) 5 R7 Wound edge necrosis 17 (17) 0 R8 Recurrence 11 (16) R9 Chronic pain 6 (6) 1 Re-admission 15 (15) R10 Mortality 0 R11 Re-operation 16 (6) 16 R12 Post-surgical complications* 23 (23) R13 * non-procedure related complications R14 R15 R16 Discussion R17 R18 R19 Large abdominal wall defects are a challenge for surgeons. The incidence of incisional hernias R20 is high and the surgical techniques to correct them challenging. Conditions associated with the R21 development of incisional hernias are suture technique, wound infection, increased abdominal R22 wall tension, metabolic connective tissue disorder and abdominal aortic aneurysms (1;2;7;13). R23 R24 In the last decade a lot of research has been done to find the best method to resolve incisional R25 hernias. Even in a large surgical department as ours, only 10 to 12 onlay procedures are performed R26 annually, which makes it difficult to evaluate techniques by randomised controlled trials. What R27 has been proven is that the use of a mesh to correct these hernias is necessary in order to avoid R28 high recurrence rates (2;3;7-10). R29 R30 The Component Separation Technique (CST) was first described by Ramirez (14) in 1990 to R31 reconstruct the abdominal wall without the use of prosthetic material. It was first tested on R32 cadavers and is based on enlarging the abdominal wall surface through translation of muscular R33 R34 layers. R35 R36 Several in vivo studies were performed after the introduction of the CST. In 2007, De Vries Reilingh R37 wrote his thesis about the correction of large abdominal wall defects and studied a modified CST R38 R39

Modified onlay technique for the repair of the more complicated incisional hernias | 27 R1 to close these defects. He added a laparoscopic element, thereby, diminishing the wound surface. R2 He states that autologous tissue repair like the CST should be reserved for patients in whom R3 prosthetic repair is contraindicated, i.e. in contaminated operations, as the rate of reherniation is R4 similar to that found after open suture repair (15). He found wound complication rates of 33% R5 and a recurrence rate of 32% using the CST (16). R6 R7 In 2007, Van Geffen also wrote a thesis about the CST for treatment of patients with large R8 R9 abdominal wall defects. He modulated the CST technique and combined it with an augmenting R10 mesh. He compared groups with and without the use of a mesh and found less recurrences in the R11 mesh group; however, the group size was too small to be significant. The overall study treated R12 95 patients and they found a recurrence of 15,6% after a median follow-up of 48 months (17). R13 Several studies (16-19) report a recurrence rate varying from 5-32% after the use of CST, but R14 most studies lack study size or duration of follow-up. R15 R16 A recent Cochrane analysis performed by den Hartog et al. states that there is insufficient evidence R17 as to which type of mesh or in which position it should be used in open ventral hernia repair. Also, R18 insufficient evidence was found to advocate the use of CST (3). R19 Nevertheless, recent studies performed in Germany and the United States report good results R20 using laparoscopic repair and a modified CST with recurrence rates as low as 5% (11;19;20). R21 R22 Conditions associated with recurrent herniation are obesity, previous abdominal aneurysm R23 R24 surgery, suture repair, chronic constipation, chronic obstructive airway disease, smoking and R25 occupational lifting (21). R26 The wide overlap of the previously described onlay technique allows a large surface area for in R27 growth of connective tissue, leading to permanent fixation within the abdominal wall. We believe R28 that, with incisional hernias, the whole scar is insufficient and, therefore, needs to be corrected R29 as a whole. The wide placement decreases the risk of recurrence and allows for the shrinkage of R30 the mesh; however this might also lead to the formation of seromas. R31 R32 Complications like wound-healing disorders, seroma, haematoma and mesh removal are more R33 common after an onlay procedure compared to other techniques (7;9). Seroma formation was R34 reported in different studies (1;7;22) to range from 0 to 63% after open mesh repair. In our R35 study, 28% patients suffered seroma formation; most of them could be treated conservatively R36 in the outpatient clinic. The high incidence of seroma formation may be caused by the extensive R37 dissection to separate the skin and subcutaneous tissue from the fascia and the subcutaneous R38 R39

28 | Chapter 2 implantation of the large mesh. It is known that a large wound surface predisposes for seroma R1 formation(16). R2 R3 R4 Fistula formation is reported in 3% of cases in the literature (2). In our study, it did not occur. R5 This is probably due to the fact that the mesh was never placed directly on the intestines. Even R6 when the hernia could not be closed great caution was taken to prevent this. Omentum was then 2 R7 placed underneath the mesh. When the intestines were, however, injured during the operation or R8 could not be covered, a mesh wasn’t used. Prosthesis removal ranges from 0-2.5% in literature; R9 in our study in only one patient the mesh had to be removed- this was due to pain. R10 R11 In this study, 101 patients were included with large incisional hernias. This large cohort study R12 evaluates the correction of large incisional abdominal wall hernias, which were corrected with R13 this particular technique. Twelve patients were excluded because of bowel injury; this, however, R14 is not related to the correction technique but shows the challenge of performing an incisional R15 hernia correction in this group. A recurrence rate of 16% was found, which is comparable to R16 other techniques. Therefore, this technique, although it has its disadvantaged, is very useful in the R17 repairing incisional hernias in patients who need an uncomplicated and fast surgical procedure. R18 R19 The advantages of the technique are the mean operation time of 63 minutes, no mortality and no R20 unacceptable technical difficulties to put in the mesh. Therefore, it seems to be an effective and R21 simple way to repair extremely large, as well as the more complicated, hernias. R22 Of course, the final indication for an abdominal wall correction needs to be tailored to the kind R23 of hernia the patient has; small or large, simple or complicated. R24 At this moment in time, there is no gold standard available, and we even state that, for incisional R25 hernias, there cannot be a gold standard because different types of incisional hernias and R26 different patient groups need a different treatment approach. Perhaps a superior classification of R27 the hernias can help to decide which therapy is best for which patient. R28 R29 Dietz et al. described a classification system in order to subdivide different kinds of incisional R30 hernias (23;24). They enlist morphology, patient body type and risk factors in the assessment R31 of prognosis. After classifying different kinds of hernias and studying these groups separately, it R32 might be easier to make surgical recommendations for these different groups. R33 R34 R35 Quality of life (QOL) is a major endpoint in evaluating surgical techniques; however, no study R36 concerning incisional hernia repair has included this. Therefore, we decided to score the QOL R37 of the patients corrected with this technique for further investigation. We will also perform a R38 R39

Modified onlay technique for the repair of the more complicated incisional hernias | 29 R1 subgroup analysis of the patients whose abdominal wall was corrected after open abdomen R2 treatment. Subsequently we hope to be able to make further recommendations for which R3 patients should be operated using this technique. R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

30 | Chapter 2 References R1 R2 1. Kingsnorth A, LeBlanc K. (2003) Hernias: inguinal and incisional. Lancet: 362(9395):1561-71. R3 2. Cassar K, Munro A. (2002) Surgical treatment of incisional hernia. Br J Surg: 89(5):534-45. R4 3. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. (2008) Open surgical procedures for incisional hernias. Cochrane.Database.Syst.Rev 2008(3):CD006438. R5 4. Urbach DR.(2005) Measuring quality of life after surgery. Surg Innov.: 12(2):161-5. 2 R6 5. Wright JG. (1999) Outcomes research: what to measure. World J Surg: 23(12):1224-6. R7 6. Heniford BT, Walters AL, Lincourt AE, Novitsky YW, Hope WW, Kercher KW. (2008) Comparison of R8 generic versus specific quality-of-life scales for mesh hernia repairs. J Am Coll.Surg: 206(4):638-44. R9 7. Luijendijk RW, Hop WC, van den Tol MP, de Lange DC, Braaksma MM, IJzermans JN et al. (2000) A comparison of suture repair with mesh repair for incisional hernia. N Engl J Med: 343(6):392-8. R10 8. Burger JW, Luijendijk RW, Hop WC, Halm JA, Verdaasdonk EG, Jeekel J. (2004) Long-term follow-up of R11 a randomized controlled trial of suture versus mesh repair of incisional hernia. Ann Surg: 240(4):578- R12 83. R13 9. Korenkov M, Paul A, Sauerland S, Neugebauer E, Arndt M, Chevrel JP et al. (2001) Classification and surgical treatment of incisional hernia. Results of an experts’ meeting. Langenbecks Arch Surg: R14 386(1):65-73. R15 10. Korenkov M, Sauerland S, Arndt M, Bograd L, Neugebauer EA, Troidl H. (2002) Randomized clinical R16 trial of suture repair, polypropylene mesh or autodermal hernioplasty for incisional hernia. Br J Surg: 89(1):50-6. R17 11. Gananadha S, Samra JS, Smith GS, Smith RC, Leibman S, Hugh TJ. (2008) Laparoscopic ePTFE mesh R18 repair of incisional and ventral hernias. ANZ J Surg: 78(10):907-13. R19 12. Barbaros U, Asoglu O, Seven R, Erbil Y, Dinccag A, Deveci U et al. (2007) The comparison of laparoscopic R20 and open ventral hernia repairs: a prospective randomized study. Hernia: 11(1):51-6. R21 13. Liapis CD, Dimitroulis DA, Kakisis JD, Nikolaou AN, Skandalakis P, Daskalopoulos M et al. (2004) Incidence of incisional hernias in patients operated on for aneurysm or occlusive disease. Am Surg: R22 70(6):550-2. R23 14. Ramirez OM, Ruas E, Dellon AL. (1990) “Components separation” method for closure of abdominal- R24 wall defects: an anatomic and clinical study. Plast.Reconstr.Surg: 86(3):519-26. R25 15. Vries Reilingh TS, Bodegom ME, van Goor H, Hartman EH, van der Wilt GJ, Bleichrodt RP. (2007) Autologous tissue repair of large abdominal wall defects. Br J Surg: 94(7):791-803. R26 16. Vries Reilingh TS, van Goor H, Rosman C, Bemelmans MH, de Jong D, van Nieuwenhoven EJ et al. R27 (2003) “Components separation technique” for the repair of large abdominal wall hernias. J Am Coll. R28 Surg: 196(1):32-7. R29 17. H.J.A.A.van Geffen, D.Kreb, R.K.J.Simmermacher, J.Olsman, Chr.van der Werken. (2009) Long term results of reconstructing large abdominal wall defects with the Companent Separation Method. In: R30 Prof.Dr.V.Schumpelick, Prof.Dr.Robert J.Fitzgibbons, editors. Recurrent Hernia: 205-11. R31 18. Lowe JB, Garza JR, Bowman JL, Rohrich RJ, Strodel WE. (2000) Endoscopically assisted “components R32 separation” for closure of abdominal wall defects. Plast.Reconstr.Surg: 105(2):720-9. R33 19. Moore M, Bax T, MacFarlane M, McNevin MS. (2008) Outcomes of the fascial component separation technique with synthetic mesh reinforcement for repair of complex ventral incisional hernias in the R34 morbidly obese. Am J Surg: 195(5):575-9. R35 20. Benhidjeb T, Benecke C, Strik MW. (2008) Incisional hernia repair: sublay or intraperitoneal onlay mesh. R36 Zentralbl.Chir: 133(5):458-63. R37 21. Vidovic D, Jurisic D, Franjic BD, Glavan E, Ledinsky M, Bekavac-Beslin M. (2006) Factors affecting recurrence after incisional hernia repair. Hernia: 10(4):322-5. R38 R39

Modified onlay technique for the repair of the more complicated incisional hernias | 31 22. Vries Reilingh TS, van Geldere D, Langenhorst B, de Jong D, van der Wilt GJ, van Goor H et al. (2004) R1 Repair of large midline incisional hernias with polypropylene mesh: comparison of three operative R2 techniques. Hernia: 8(1):56-9. R3 23. Dietz UA, Hamelmann W, Winkler MS, Debus ES, Malafaia O, Czeczko NG et al. (2007) An alternative classification of incisional hernias enlisting morphology, body type and risk factors in the assessment of R4 prognosis and tailoring of surgical technique. J Plast.Reconstr.Aesthet.Surg: 60(4):383-8. R5 24. Winkler MS, Gerharz E, Dietz UA. (2008) Overview and evolving strategies of ventral hernia repair.]. R6 Urologe A: 47(6):740-7. R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

32 | Chapter 2 Chapter 3

Health-related quality of life in patients treated

for incisional hernia with an onlay technique

M.M. Poelman J.F. Schellekens B.L.A.M. Langenhorst W.H. Schreurs

Hernia. 2010 Jun;14(3):237-42. R1 Abstract R2

R3 Background An incisional hernia is a frequent complication of abdominal surgery. Repair of R4 incisional hernias comes with a high risk of reherniation and serious complications. With the R5 introduction of mesh repair, recurrence rates have decreased and subsequent clinical outcomes R6 have improved. Whereas further research needs to be done to improve complication rates and R7 recurrence, the focus has now been placed on quality-of-life outcomes in patients undergoing R8 R9 these repairs. The aim of this study was to investigate the long-term health-related quality-of-life R10 (HRQL) of patients who were treated for incisional hernias using an onlay technique. R11 R12 Patients & Methods Over a period of 10 years (1997-2007) 101 patients with an incisional hernia R13 were treated with an onlay marlex mesh, fixed on the fascia with skin staples. Of the 101 patients R14 there were 45 males and 56 females, their mean age was 55 years. Nine patients died and 13 R15 were lost during follow up. Of the remaining 79 patients, 8 refused to participate. The mean R16 follow-up time was 64 months (normal distribution, SD 34 months). The Short Form 36 (SF- R17 36©) and the Karnofsky Performance Scale (KPS) and a semi-structured interview were used to R18 measure HRQL. R19 R20 Results Seventy-one of the 101 patients were evaluated at our outpatient clinic. Twenty-one R21 patients (20%) had an open abdomen treatment in their medical history. The median admission R22 time was 4,5 days (Quartiles 3-6,25). Mean follow-up time was 64 months (SD 35 months). A R23 R24 seroma was reported in 27 of the 101 patients (27%) and a wound infection in 22 patients (21%) R25 of which 5 patients had to be re-operated. Only if a patient was evaluated at our out-patient clinic R26 could reherniation be scored; this occurred in 11 of 71 patients (16%). R27 The evaluation of HRQOL showed equal SF-36© scores for patients treated for an incisional hernia R28 compared to their matched controls. Patients with a history of an open abdominal treatment did R29 not score significantly lower compared to patients without such a treatment. The median KPS R30 score was 75, indicating that activities could be performed with effort and patients had some R31 signs of disease. R32 R33 Conclusion HRQL is the same in patients treated for an incisional hernia compared to the matched R34 controls. Therefore, the onlay technique seems to be an acceptable method to repair large R35 incisional hernias. R36 R37 R38 R39

34 | Chapter 3 Introduction R1 R2

Incisional hernias are a frequent complication of abdominal surgery, with an incidence of 10-23% R3 R4 (1, 2). Although they can be treated conservatively, patients frequently choose to have them R5 corrected surgically. Incisional hernias enlarge over time and might give aesthetic complaints. R6 They can cause serious complications like strangulation or incarceration of the bowel. The quality R7 of life of these patients, as well as their chances for re-employment, is reduced (3). Of all patients R8 with an incisional hernia, 20% is treated conservatively (4). The major reason to seek surgical care R9 is to improve the quality of life (5-7). 3 R10 R11 Repair of these hernias comes with a high recurrence rate, high morbidity and, therefore high R12 costs. Complications like seroma formation and wound infections are usual (8). These problems, R13 in combination with the technical difficulties, might discourage many surgeons to perform an R14 abdominal wall reconstruction. Still, these hernias, especially the larger ones, can give invalidating R15 complaints such as bulging of the abdominal wall, chronic wounds and immobility necessitating R16 surgical treatment (9). The treatment of large incisional hernias is a challenge for surgeons and a R17 risk for the patient undergoing the surgery. R18 R19 R20 Many aspects of incisional hernia surgery are to be answered, as there is no gold standard for R21 this procedure (1,3,10). This is probably, at least partially, due to the multifactorial aetiology R22 of abdominal wall defects. Different methods of hernioplasty and several prosthetic materials R23 are currently used. Recurrence rates up to 36% have been reported even after mesh repair R24 (3,8,11,12). A recent Cochrane review states that there is insufficient evidence as to which mesh R25 position or which type of mesh should be used (3). R26 R27 A variety of measures can be used to determine the outcome of surgical treatment. They can be R28 categorized as utilization measures, clinical measures, traditional measures of convalescence and R29 functional status/health-related quality-of-life (HRQL) measures (5). Improvement of the quality R30 of life is a way for patients to judge the effect of their treatment (5-7). With improving clinical R31 outcomes, HRQL has become a major endpoint in the treatment of patients (5, 13). HRQL has R32 been assessed in patients with an open abdominal treatment, severe peritonitis and patients R33 R34 undergoing repair (14-16). Data on HRQL in patients treated for incisional hernia R35 are not widely available. The assessment of HRQL yields essential information of the somatic R36 success of treatment and helps to determine the overall effect of surgery on patients with R37 incisional hernias. The outcome might help to determine when to correct an incisional hernia and R38 with which technique. R39

Health-related quality of life in patients treated for incisional hernia with an onlay technique | 35 R1 The aim of this study was to investigate the long-term HRQL in patients treated for incisional R2 hernias with an onlay procedure. We performed a matched-control retrospective study. R3 R4 R5 Methods R6 R7 Patients R8 R9 All patients who had an incisional hernia operation between January 1996 and January 2007 R10 were selected and put onto a database. Out of this group, the patients who were operated using R11 an onlay polypropylene mesh, with a minimum size of 10x20 cm fixed with skin staples, were R12 included. This onlay-technique was only used when a large, complicated hernia was present; R13 smaller, simple hernias were corrected using laparoscopy or open techniques. R14 R15 Follow-up R16 All patients still alive were sent a letter to ask if they were willing to visit our outpatient clinic for R17 an evaluation. Patients who opted not to participate were asked for what reason. After written R18 consent was given, patients were invited to our outpatient clinic for an interview and physical R19 examination of their abdomen. A recurrent hernia was diagnosed when a facial defect could be R20 palpated when lifting the head from the examination table to raise the abdominal pressure. If this R21 examination was not conclusive, which was the case in two patients, a CT-scan was performed. R22 Demographics, pre-, peri- and postoperative data were collected. Post-operative outcomes were R23 R24 wound-edge necrosis, wound infection, fistulas, seromas, hematoma, re-admission and length of R25 stay, re-operation, mortality and reherniation in the follow-up. R26 R27 HRQL questionnaires R28 HRQL was assessed using the Study Short Form 36 (SF-36©) and the Karnofsky Performance R29 Status (KPS). The SF-36© is one of the most widely used generic measures in HRQL and is currently R30 the gold standard for measuring quality of life in patients who have undergone incisional hernia R31 repair in the US (7, 17). The SF-36© has been validated for many diseases and has been translated R32 into several languages, including Dutch (18). The SF-36© consists of 36 multiple-choice items that R33 are used to calculate eight subscales: physical functioning (PF), role physical (RP), bodily pain (BP), R34 general health (GH), vitality (VT), social functioning (SF), role emotional (RE), and mental health R35 (MH). The eight subscales can be converted via a syntax into values ranging from 0 (poor health) R36 to 100 (best health), resulting in two major subscales: physical health and mental health. Three R37 of the eight SF-36© subscales (physical functioning, bodily pain and role physical) were considered R38 R39 as main outcomes.

36 | Chapter 3 The KPS was first described in 1949 and measures functional performance on a decimal scale R1 from 0 to 100, where 100 is perfect health and 0 is death. Patients have to indicate which R2 statement applies best to their condition, where 100 indicates that the patient can fully function R3 R4 and perform all activities of daily life independently, with no evidence of disease. R5 Patients were asked to score their health after the hernia correction and satisfaction of the R6 treatment on a ten-point scale, were 10 was the best and 1 the worst condition possible, to R7 measure the self-perceived health. R8 R9 Statistical analysis 3 R10 All data was put in an SPSS database. The Pearson χ² test was used to compare the study R11 population to the non-responders regarding patient characteristics. R12 A national database from the Netherlands Cancer Institute and the Netherlands Organization for R13 Applied Scientific Research provided values of the Medical Outcome Study Short Form 36 (SF-36©) R14 for a matched population without an incisional hernia. Patients were matched with controls from R15 the database with respect to age, sex and the presence of cancer. R16 These values were compared to the results of the patients treated for incisional hernias. A R17 matched-pair analysis was performed using the Wilcoxon signed rank test. Spearman correlation R18 R19 coefficients were calculated between HRQL of life scores and history of open abdomen. Two- R20 tailed p<0.05 was considered significant. All statistical analysis was performed using SPSS© R21 software (version 14.0; SPP, Chicago, Illinois, USA). R22 R23 R24 Results R25 R26 Patients R27 Between January 1996 and January 2007, 107 patients with an incisional hernia were treated R28 using this specific onlay technique. The same two surgeons operated all patients selected, except R29 six. These 6 patients were excluded from this study because it was not certain that exactly the R30 same technique was used. Therefore, 101 patients were included in this study. R31 Mean age at time of operation was 55 years (normal distribution, SD 14,4 years). There were 45 R32 (44%) males and 56 (56%) females. Nine of these patients had died at time of evaluation. These R33 R34 deaths were not related to the hernia correction. Thirteen patients were lost to follow up. Eight R35 patients refused to participate, three of them because they were dissatisfied and five because R36 of logistic reasons. Therefore, it was possible to evaluate only 71 of the 101 patients in our R37 outpatient clinic. There were 30 males and 41 females. R38 R39

Health-related quality of life in patients treated for incisional hernia with an onlay technique | 37 R1 Seroma formation, infection and co morbidity was reported using the medical records of all 101 R2 patients. Recurrence could only be scored if a patient was seen at the out-patient clinic and is, R3 therefore, only mentioned in the out-patient controlled group (n=71). R4 R5 The indications for surgery were complaints of bowel obstruction, i.e. patients felt pain or R6 had difficulties passing stool; only a minority of the patients found the hernia aesthetically R7 unacceptable. R8 R9 R10 The most prevalent co-morbidity (table 1) is obesity (mean BMI >29); 43 patients had a BMI R11 of more than 29. Nineteen patients had cardiovascular disease. There were 11 diabetics, 27 R12 smokers and 5 patients used corticosteroids. Seventy patients (70%) developed an incisional R13 hernia after a medial laparotomy. Eighteen patients had a recurrent hernia after former incisional R14 hernia repair using another technique. There were 21 patients (20%) with a history of open R15 abdomen treatment. R16

R17 Table 1: Baseline characteristics of patients R18 % mean SD minimum maximum R19 gender 55% female R20 malignancy at time of operation 15% diabetes 7% R21 cardiac disease 16% R22 pulmonary disease 18% R23 smoker 25% R24 use of corticosteroids 3% R25 history of open abdomen treatment 20% ASA-score* at time of operation 1,8 0,6 1 3 R26 BMI 29 6 19 48 R27 R28 *American society of Anesthesiologists R29 R30 The primary outcome for this study was the SF-36© score. Three of the eight SF-36© subscales R31 (physical functioning, bodily pain and role physical) were considered as main outcomes19 (table R32 1). Secondary outcomes were seroma formation, wound infection, recurrence, length of hospital R33 stay in days, aesthetic results, patient satisfaction, operating time in minutes and post-operative R34 pain. R35 R36 R37 R38 R39

38 | Chapter 3 Overall results for quality of life R1 The scores of the SF-36© subscales in patients treated for incisional hernias are not significantly R2 lower compared to the matched controls (Table 2). There was no difference between the two R3 R4 groups; patients scored equal in all subscales. Patients with a history of an open abdominal R5 treatment did not score significantly lower on the SF-36© compared to patients without such a R6 treatment. R7 R8 Karnovsky scale R9 The median score of KPS was 75 (range 30-90), indicating that activities could be performed with 3 R10 effort and patients had some signs of disease. R11 R12 Self-perceived health R13 Measuring self-perceived health on a 10-point-scale, 80% scored above 6 and 60% scored above R14 7,5. Scoring overall satisfaction of the surgical procedure, 75% scored above 6 and 50% scored R15 above 7,5. R16 R17 R18 Table 2: SF-36© outcome Study group Controle Group R19 R20 N mean sd N mean sd t-value p-value Physical functioning 69 71,0 24,0 71 74,1 26,8 0,72 0,47 R21 Role physical 67 63,4 42,7 71 68,7 41,6 0,73 0,47 R22 Bodily pain 69 68,2 24,4 71 68,2 25,4 0,01 0,99 R23 General health perceptions 67 61,0 24,1 71 64,3 21,6 0,86 0,39 R24 Vitality 69 63,7 21,5 71 64,3 22,4 0,17 0,87 Social functioning 69 76,3 27,2 71 81,0 24,6 1,08 0,28 R25 Role emotional 65 74,4 39,9 71 75,6 36,9 0,19 0,85 R26 Mental health 69 75,8 17,9 71 72,5 20,5 1,01 0,31 R27 R28 Table 3: secondary outcomes; evaluated patients compared to total R29 patients seen in out-patient clinic n=71 using medical records N=101 R30 woundedge necrosis 11 17 R31 seroma formation 18 27 R32 wound-infection 16 22 recurrence 11 unknown R33 R34 R35 R36 R37 R38 R39

Health-related quality of life in patients treated for incisional hernia with an onlay technique | 39 R1 Discussion R2

R3 Incisional hernia is a common complication after abdominal surgery, which causes impressive R4 morbidity for patients suffering from these hernias, especially when these hernias are large. R5 Complications like wound healing disorders, seroma, haematoma and mesh removal are more R6 common after an onlay procedure compared to other techniques (8,10). The quality of life and R7 chances for re-employment of these patients are reduced (3). It is therefore necessary to find the R8 R9 best possible solution to treat them. R10 R11 In the last decade, much research has been done to find the best method to resolve incisional R12 hernias. Even in a large surgical department as ours, only 10 to 12 onlay procedures are performed R13 annually, which makes it difficult to evaluate techniques by randomised controlled trials. What R14 has been proven is that the use of a mesh to correct these hernias is necessary in order to avoid R15 high recurrence rates (1,10,12). A gold standard for the position of the mesh and how to place it R16 in the abdomen, i.e open or laparoscopic, is not yet found (3). Although these technical questions R17 are useful to study, functional outcome and quality of life after hernia repair has become the R18 more important question. R19 R20 Disease specific measures focus on a particular health condition and are useful to detect the R21 changes resulting from a specific treatment. There is currently only one incisional hernia quality- R22 of-life questionnaire available, named the Carolinas Comfort Scale© (CCS) (7). The CCS is not R23 R24 validated in Dutch and could, therefore, not be used in our study. Generic measures cover a R25 broader spectrum of quality-of-life, provide a global assessment of a patient’s overall health and R26 allow comparisons to other health conditions, different interventions and populations (5). We, R27 therefore, chose to use the SF-36©. R28 R29 Generic quality-of-life measurements like the SF-36© are used primarily to compare outcomes R30 across different interventions and populations. Mesh hernia repair can affect each of the domains R31 of the SF-36©. Although it is not a disease specific measurement, it is an adequate way to score R32 HRQL (7,17). R33 R34 In our study, patients who were treated for an incisional hernia had an equal HRQL score, R35 measured with the SF-36©, compared to their matched controls. Both groups are matched based R36 on prevalence of cancer, age and sex. The comparable outcomes of this matched-pair analysis R37 might be explained partially by the high incidence of cancer (17,18,20,21) as it is known that R38 R39

40 | Chapter 3 this has a great influence on the HRQL. Since the questionnaires were filled in anonymously, R1 it was impossible to perform an individual match. It was, therefore, not possible to perform R2 a subgroup analysis. Improvement of quality of life through surgery can only be measured by R3 R4 a validated questionnaire before and after the surgical interference. A prospective study is, R5 therefore, necessary. R6 R7 The average outcome of 75 on the KPS shows that patients have some signs of disease and are R8 able to take care of themselves, but are not always able to carry on normal activity or to do active R9 work. One patient even scored as low as 30, indicating that (s)he is severely disabled; hospital 3 R10 admission is indicated although death is not imminent. One could wonder whether this is due to R11 the hernia correction. R12 R13 The study by Burger et al. published in 2004 showed that, depending on which surgical method R14 was used, 64-77% of patients were satisfied after incisional hernia repair (12). The main reason R15 for dissatisfaction was a recurrent hernia. Of the 181 patients in this trial, 20-23% reported scar R16 pain and 18-39% suffered bowel pain in the last year. The cosmetic result was satisfying for 47- R17 52% of the patients (12). R18 R19 In measuring self-perceived health, 80% of the patients found their overall health status R20 satisfactory. Scoring general satisfaction of this particular surgical procedure, 75% scored above R21 6. The recurrence rate was 16% (seven patients). Cosmetic satisfaction is to be examined. R22 R23 © A study published in 2005 using the SF-36 showed improved physical function scores four R24 months after mesh repair (22). In general, the extent to which postoperative pain interferes R25 with function has not been well described (7). In this study, six (6%) patients suffered chronic R26 pain. These patients were specifically asked whether they suffered pain from the numerous skin R27 staples. Although many patients reported to feel the staples, only 2 patients suffered major pain R28 due to the staples. One patient chose to have the mesh removed; whether or not this relieved the R29 pain is not known, as he did not visit the out patient clinic again. R30 R31 Dietz et al described a classification system in order to subdivide different kinds of incisional R32 hernias (23,24). They enlist morphology, patient body type and risk factors in the assessment R33 R34 of prognosis. After classifying different kinds of hernias and studying these groups separately, it R35 might be easier to make surgical recommendations for these different groups. R36 R37 R38 R39

Health-related quality of life in patients treated for incisional hernia with an onlay technique | 41 R1 In this study, 30 patients were lost to follow-up. Although the complication rate was not higher R2 in this group (table 3), it is possible that their HRQL was worse than in the group which we R3 evaluated. This might have a positive impact on the outcome of this study. In the attempt to state R4 something about the HRQOL in patients whose incisional hernia was corrected with an onlay R5 mesh, we might have to conclude that this group is to small to reject the null hypothesis. R6 R7 Quality of life is an important but difficult end-point in surgery. Overall, the patients in this study R8 R9 had significant co-morbidity and also suffered from their incisional hernias. Most of them choose R10 to have their hernia corrected with this onlay technique because it is fast and simple and allows R11 a short hospital stay. Although this technique has it disadvantages, it is a very useful in correcting R12 an incisional hernia in patients who need a uncomplicated and fast procedure. Is it possible that R13 their expectations influence the level of satisfaction? We do not know. We do not even know if R14 is relevant. What we do know is that, after incisional hernia correction, 80% of the patients had R15 a satisfactory health status. R16 R17 The management of an incisional hernia is currently not standardized (10) and it is probably R18 not possible to allocate a gold standard for al incisional hernias as a whole. They cannot be R19 considered as one aetiology. Different types of incisional hernias and different patient groups R20 need a different treatment approach. In future studies, besides complications and reherniation R21 rate, HRQOL should be a major endpoint, scored before and after surgical interference. R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

42 | Chapter 3 References R1 R2 1. Cassar K, Munro A. Surgical treatment of incisional hernia. Br J Surg 2002; 89: 534-45. R3 2. Kingsnorth A, LeBlanc K. Hernias: inguinal and incisional. Lancet 2003; 362: 1561-71. R4 3. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. Open surgical procedures for incisional hernias. R5 Cochrane Database Syst Rev 2008; CD006438. 4. Nieuwenhuizen J, Kleinrensink GJ, Hop WC, Jeekel J, Lange JF. Indications for incisional hernia repair: R6 an international questionnaire among hernia surgeons. Hernia 2008; 12: 223-5. R7 5. Urbach DR. Measuring quality of life after surgery. Surg Innov 2005; 12: 161-5. R8 6. Wright JG. Outcomes research: what to measure. World J Surg 1999; 23: 1224-6. R9 7. Heniford BT et al. Comparison of generic versus specific quality-of-life scales for mesh hernia repairs. J R10 Am Coll Surg 2008; 206: 638-44. 3 R11 8. Luijendijk RW et al. A comparison of suture repair with mesh repair for incisional hernia. N Engl J Med 2000; 343: 392-8. R12 9. Vries Reilingh TS et al. Repair of large midline incisional hernias with polypropylene mesh: comparison R13 of three operative techniques. Hernia 2004; 8: 56-9. R14 10. Korenkov M et al. Classification and surgical treatment of incisional hernia. Results of an experts’ R15 meeting. Langenbecks Arch Surg 2001; 386: 65-73. 11. Korenkov M et al. Randomized clinical trial of suture repair, polypropylene mesh or autodermal R16 hernioplasty for incisional hernia. Br J Surg 2002; 89: 50-6. R17 12. Burger JW et al. Long-term follow-up of a randomized controlled trial of suture versus mesh repair of R18 incisional hernia. Ann Surg 2004; 240: 578-83. R19 13. Velanovich V. The quality of quality of life studies in general surgical journals. J Am Coll Surg 2001; 193: 288-96. R20 14. Kriwanek S et al. Long-term outcome after open treatment of severe intra-abdominal infection and R21 pancreatic necrosis. Arch Surg 1998; 133: 140-4. R22 15. Scheingraber S, Kurz T, Dralle H. Short- and long-term outcome and health-related quality of life after R23 severe peritonitis. World J Surg 2002; 26: 667-71. R24 16. van Hanswijck dJ, Lloyd A, Horsfall L, Tan R, O’Dwyer PJ. The measurement of chronic pain and health- related quality of life following inguinal hernia repair: a review of the literature. Hernia 2008. R25 17. Aaronson NK et al. Translation, validation, and norming of the Dutch language version of the SF-36 R26 Health Survey in community and chronic disease populations. J Clin Epidemiol 1998; 51: 1055-68. R27 18. Visschers RG et al. Health-related quality of life in patients treated for enterocutaneous fistula. Br J Surg R28 2008; 95: 1280-6. 19. Bitzer EM, Lorenz C, Nickel S, Dorning H, Trojan A. Patient-reported outcomes in hernia repair. Hernia R29 2008; 12: 407-14. R30 20. Kriegsman DM, Deeg DJ, Stalman WA. Comorbidity of somatic chronic diseases and decline in physical R31 functioning:; the Longitudinal Aging Study Amsterdam. J Clin Epidemiol 2004; 57: 55-65. R32 21. Kriegsman DM, Deeg DJ, van Eijk JT, Penninx BW, Boeke AJ. Do disease specific characteristics add to the explanation of mobility limitations in patients with different chronic diseases? A study in The R33 Netherlands. J Epidemiol Community Health 1997; 51: 676-85. R34 22. Conze J et al. Randomized clinical trial comparing lightweight composite mesh with polyester or R35 polypropylene mesh for incisional hernia repair. Br J Surg 2005; 92: 1488-93. R36 23. Dietz UA et al. An alternative classification of incisional hernias enlisting morphology, body type and risk factors in the assessment of prognosis and tailoring of surgical technique. J Plast Reconstr Aesthet R37 Surg 2007; 60: 383-8. R38 R39

Health-related quality of life in patients treated for incisional hernia with an onlay technique | 43 24. Winkler MS, Gerharz E, Dietz UA. [Overview and evolving strategies of ventral hernia repair.]. Urologe R1 A 2008; 47: 740-7. R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

44 | Chapter 3 Chapter 4

Open abdomen treatment:

planned ventral hernia or delayed fascial closure?

A review of the literature compared with daily practice

M.M. Poelman H.J. Bonjer W.H. Schreurs

Submitted R1 Abstract R2

R3 Introduction Open abdomen treatment is leaving the fascial edges and skin intentionally open after R4 a laparotomy. The advantages of this treatment are a reduction of the intra-abdominal pressure, R5 drainage of abdominal cavity and visualization of the intra-abdominal contents postoperatively. R6 Open abdomen treatment may lead to several serious complications. To prevent evisceration the R7 open abdomen requires temporary abdominal closure (TAC). The aim of TAC is either delayed R8 R9 primary fascial closure or development of a ‘planned ventral hernia’. There is no gold standard for R10 TAC and several techniques are available. Although many studies have evaluated the success rate R11 of TAC-methods in terms of primary closure rate, little is known about the (long-term) results. R12 Does delayed fascial closure really benefit the severely ill patient and at what cost should it be R13 achieved? R14 The aim of this research was to compare the outcomes of primary fascial closure and planned R15 ventral hernia after OAT. R16 R17 Methods Retrospective analysis of our own patients in a large teaching and a university hospital. R18 Review of the existing literature on OAT and TAC. R19 R20 Discussion Level 1 and 2 evidence for OAT and the management after this treatment is non- R21 existent. If OAT is necessary to prevent the patient from dying, the temporary closure should R22 do the same. The way the abdomen is temporally closed, should not be dependent on the skills R23 R24 of the surgeon on duty. It has to be a very easy procedure and should not have a large risk of R25 complications itself. TAC with anticipation of a planned ventral hernia might be a good and R26 simple option. We plea to keep it simple. R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

46 | Chapter 4 Introduction R1 R2

Open abdomen treatment (OAT) is a sometimes necessary but undesirable treatment in severely R3 R4 ill patients. Intentional opening of the abdominal cavity is a lifesaving procedure in many acute R5 situations leading to intra-abdominal hypertension and abdominal compartment syndrome. In R6 case of visceral or retroperitoneal oedema due to shock or reperfusion, the intra-abdominal R7 pressure may rise to dangerous levels, leading to organ dysfunction. Leaving the abdomen open R8 allows for visceral and renal perfusion as well as adequate pulmonary function (1). R9 Open abdomen treatment is leaving the fascial edges and skin intentionally open after a R10 laparotomy. The advantages of this treatment are a reduction of the intra-abdominal pressure, R11 drainage of abdominal cavity and visualization of the intra-abdominal contents postoperatively. R12 Open abdomen treatment is the standard of care in challenging clinical situations that can be R13 summarized in the following four clinical scenarios. The septic contaminated abdomen that cannot 4 R14 be closed or when second-look operation is mandatory. The patient with a tense abdomen after R15 massive resuscitation or a prolonged surgical procedure that is at risk of developing abdominal R16 compartment syndrome and may be a candidate for prevention. R17 Open abdomen treatment may lead to several complications such as dehydration, evisceration R18 R19 and the most serious are the development of enteroatmospheric fistulas and giant ventral hernia, R20 both associated with prolonged treatment and failure to close the open abdomen. R21 To prevent evisceration the open abdomen requires temporary abdominal closure (TAC), which is R22 used to postpone definite closure until predisposing factors causing pathologic elevation of the R23 intra abdominal pressure or sepsis are resolved. The aim of TAC is either delayed primary fascial R24 closure or development of a ‘planned ventral hernia’. The ideal TAC stabilizes the abdominal R25 wall, prevents for lateral retraction of the abdominal wall muscles, minimizes trauma to the skin, R26 fascia and bowel and is easy to apply, remove and replace. There is no gold standard for TAC and R27 several techniques are available, including the Bogota bag, absorbable mesh and the KCI VAC R28 dressing (2) (3). R29 R30 Although many studies have evaluated the success rate of TAC-methods in terms of primary R31 closure rate, little is known about the (long-term) results. Does delayed fascial closure really R32 benefit the severely ill patient and at what cost should it be achieved? What is known about the R33 R34 long-term results? R35 The results of a planned ventral hernia are hard to find either: does this treatment negatively R36 influence the patients’ prognosis? On the long run, should a ventral hernia repair be performed R37 after the patient recovered or is a conservative management acceptable? And what about quality R38 of life (QOL) in these patients? R39

Open abdomen treatment: planned ventral hernia or delayed fascial closure? | 47 R1 The aim of this research was to compare the outcomes of primary fascial closure and planned R2 ventral hernia after OAT. The incidence and indications for OAT as well as the management of R3 the abdominal wall after this treatment was started were studied in two hospitals: a university R4 hospital and a large teaching hospital. Evaluation of the results of our strategy of temporary R5 closing of the abdomen was performed. Furthermore the management after a ‘planned ventral R6 hernia’ developed was evaluated. R7 The literature on OAT was reviewed to find evidence to support a certain temporary abdominal R8 R9 coverage and a systematic review was performed to see if there is any evidence to advocate a R10 certain treatment of the abdominal wall after OAT. R11 R12 R13 Methods R14 R15 An evaluation of all the patients who had an OAT was done. The selection procedure took place R16 in two hospitals; a university hospital and a large teaching hospital. R17 In the both hospitals a search was performed for all patients who were admitted to the Intensive R18 Care Unit after a laparotomy. The patient files were searched for the following terms: ‘open R19 abdomen treatment’ and ‘vacuum closure of the abdomen’. The surgical files for the code “re- R20 exploration of the abdomen, because of post-operative complications” were also selected. R21 Patients who met all these criteria were included. In the university hospital patients were included R22 between 2005 and 2010, in the teaching hospital between 2007 and 2010. R23 R24 R25 R26 Results R27 R28 Incidence R29 During this period 2994 laparotomies were performed in both hospitals (1251 in the University R30 hospital (UH) and 1743 in the Teaching Hospital (TH)). R31 After laparotomy 883 patients had been admitted to the ICU (264 UH, 559 TH), and all these R32 files were studied. Finally 55 patients (UH 29, TH 26) met all the criteria and were selected for R33 evaluation. R34 Six patients were excluded because there was no follow up; two were transferred to another R35 hospital after surgery and lost for follow up and four patients died within the first 8 hours after R36 surgery. R37 R38 R39

48 | Chapter 4 Resulting in 49 patients who were included in this study: 21 females and 28 males. Mean age at R1 time of surgery was 70 years for females and 62 years for males. Eleven patients died during the R2 hospital admittance. Patients’ characteristics are listed in table 1. The mean length of hospital stay R3 R4 was 42,5 days (table 2). R5 R6 Table 1: baseline characteristics R7 Patient characteristics Number Extremes Gender male/female 28/22 R8 Age (mean) 65,82 R9 Cardiac disease(s) 32% R10 Pulmonary diseases/smokers 36% R11 Malignancy 34% BMI (mean) 25,80 16,2 - 41,52 R12 Corticosteroid use 5% R13 Diabetes 12% 4 R14 R15

Table 2: results R16 Results N= Days Extremes R17 Deaths during admittance 11 R18 Length of hospital stay (mean) 65,5 42,5 3 - 245 R19 Length of stay in ICU 22,8 22,7 1 - 86 R20 R21 Indications R22 These patients were all reported ASA 3, 4 and 5 according to the ASA physical status classification. R23 Most patients required an acute surgical intervention because of sepsis and/or shock. There were R24 various reasons why the fascia could not be closed (table 3); anastomotic dehiscence frequently R25 caused abdominal sepsis and/or an abdominal compartment syndrome. In some patients a known R26 bowel perforation was put underneath a Vicryl mesh and the fascia was left open to drain the R27 abdominal cavity. Damage control surgery has not been reported. R28 R29 Table 3: Causes of open abdomen treatment R30 Indication for Open Abdomen Treatment N= R31 Abdominal sepsis after anastomotic dehiscence 20 R32 Short bowel perforation (iatrogenic and spontaneous) 8 R33 Bowel ischemia due to vascular occlusion 4 ACS due to bleeding 5 R34 Fascial dehiscence 5 R35 Other 7 R36 R37 R38 R39

Open abdomen treatment: planned ventral hernia or delayed fascial closure? | 49 R1 Management of the open abdomen R2 In all but two patients temporary closure was achieved with an absorbable mesh i.e. Vicryl. The R3 mesh was sewn at the fascial edges or stapled onto the skin if the fascia tensile strength was to R4 low. A Vacuum system and a Bogota bag were both only used once. R5 R6 Mortality and morbidity rate R7 There were 13 patients with entero-atmospheric fistulas: Eight patients developed fistulas after R8 R9 the OAT was started, in 5 patients an OAT was started because of the fistula formation. Sixteen R10 patients were treated for intra-abdominal abscesses after the OAT was started. Eleven patients R11 died during their hospital stay, 4 died within 48 hours after the OAT was started. Causes of death R12 were: 7 sepsis, 2 intra-abdominal bleeding, 1 myocardial infarction, 1 necrotizing pancreatitis. R13 R14 Follow up R15 Of the 49 patients, 11 died during hospital stay: cause of death was due to their initial disease. Of R16 the remaining 38 patients, 19 patients did not have a ventral hernia repair until now. Of the 19 R17 patients that did have a surgical incisional hernia repair, 9 were reconstructed using a large onlay R18 mesh, we reported on these patients earlier (6). Five patients had a primary suture closure (all R19 after planned closure of their or ), two had a Ramirez, one had a sublay repair R20 and one had an inlay repair. Of these 19 patients, three recurrences were reported in the follow- R21 up: one after the onlay mesh repair, one after primary suture closure and one after sublay repair. R22 The patients still alive were contacted to ask them about their quality of life. We specifically R23 R24 asked them if they still had problems concerning their abdominal wall. Five patients were lost for R25 follow up because they died of other causes in the mean time. Twenty-seven of the 31 patients R26 responded (table 4). R27 As table 4 shows, no difference between the patients who had and the patients who hadn’t R28 a correction of the incisional hernia could be demonstrated. The patients equally dislike their R29 abdominal wall appearance and still have the same wish for surgical interference. Patients without R30 surgical correction tend to have more incarceration of bowel in the hernia, however with these R31 small numbers of patients, statistical significance cannot be reached. R32 R33 Table 4: Follow-up After incisional hernia repair. N=14 After conservative treatment. N=13 R34 VAS score (mean) 2 (0-7) 1 (0-7) R35 Use of a bondage 3 2 R36 Incarceration of a bowel 1 4 R37 Cosmetics; unhappy with the result 12 11 Wish for surgical repair 5 5 R38 R39

50 | Chapter 4 Discussion R1 R2

Incidence R3 R4 Little is known about the incidence of open abdomen treatment. Some articles suggest that 25% R5 of all patients who undergo a laparotomy because of a trauma will be treated with a (temporary) R6 open abdomen, according to the damage control principle (4). R7 Leaving the abdomen open because of a damage control purpose however is thought to be R8 another aetiology than an OAT because of sepsis or ACS. It has been shown that trauma patients R9 whose abdomen was left open were more likely to have primary fascial closure (5). Nevertheless, R10 these groups of patients are frequently studied together. In our study we found an incidence of R11 less than 2% (UH 1.9%, TH 1.5%,) of all performed laparotomies during the study period. R12 A single centre study from England, reports only 29 patients in 6 years whose abdominal walls R13 were left open because of sepsis (6). A Swedish study reports 151 patients with an open abdomen 4 R14 treatment (for more than five days; the majority because of sepsis or ACS) in 4 hospitals within R15 41 months (7). Prichayudh et al reported only 37 patients, with sepsis or ACS, who had an open R16 abdomen treatment in over 6 years in a Thai hospital (8). Other retrospective studies do not R17 specifically search for patients treated with an open abdomen, but search for the device chosen R18 R19 to treat their open abdomen, for example, the use of a Vacuum-dressing (9) (10). Studies on the R20 number of patients requiring OAT according to the number of performed laparotomies were not R21 found. R22 R23 Temporary abdominal closure R24 OAT is mend to be a live saving procedure, however, once the abdomen is left open a potentially R25 dangerous situation is created for the individual patient. Early complications of an open abdomen R26 treatment are increased water and electrolyte loss, evisceration and entero-cutaneous fistula R27 formation. Late complications are entero-cutaneous fistula formation, lateral retraction of the R28 fascial edges and development of a large ventral hernia (6). The last one is rather a consequence R29 than a complication, as it is not an adverse or unforeseen effect. Entero-cutaneous or entero- R30 atmospheric fistula formation is the most severe complication. R31 Therefore temporally closure is demanded. The aim of the abdominal coverage is to make R32 sure that the abdominal content stays inside, to allow for drainage, to keep the fascial edges R33 R34 together and to prevent the formation of adhesions between the viscera and the abdominal R35 wall. Furthermore, the coverage should not damage the viscera underneath it and should be R36 easy to apply and remove. The temporary closure may facilitate delayed primary fascial closure, R37 this is however not the main goal. If the plan for delayed closure fails, a ‘planned ventral hernia’ R38 R39

Open abdomen treatment: planned ventral hernia or delayed fascial closure? | 51 R1 is created. Articles examining the different temporary abdominal coverages are widely available R2 however, they tend to differentiate for the cause of the open abdomen treatment and usually R3 study small numbers (3). R4 R5 A method to cover and protect a laparotomy wound is the application of a Bogota-bag. A Bogota R6 bag is a sterile plastic bag used for closure of abdominal wounds. It is generally a sterilized, 3 liter R7 genitourinary irrigation bag that is sewn to the skin or fascia of the anterior abdominal wall. Its R8 R9 use was first described by Oswaldo Borraez while a resident in Bogota, Colombia. R10 This method is cheap, easy to use and always available. Disadvantage is it does not prevent the R11 fascia to shift laterally. The Bogota bag is very popular in the treatment of gastroschisis in new- R12 born. R13 Another method to cover the open abdomen is the use of a mesh. Absorbable meshes have R14 been used for many years to close the abdomen. They are easy to handle, widely available and R15 resistant to infection. An absorbable mesh allows for the development of a ‘planned ventral R16 hernia’ when a delayed primary fascial closure cannot be achieved. The disadvantage of the R17 use of an absorbable mesh is the risk for entero-atmospheric fistula formation (11). The risk is R18 reported to be up to 7% but is also related to the severity of the abdominal injury. Advantage of R19 an absorbable mesh is that it can be left in situ. R20 The third method to cover an open abdomen is the use of a Vacuum system. The technique has R21 first been reported in the mid-eighties and has evaluated since (12). A non-adherent plastic drape R22 is placed beneath the anterior abdominal wall to protect the viscera. Coverage is created with the R23 R24 use of sponges and drapes, and a controlled sub-atmospheric pressure is connected to a small R25 opening in the drape. This technique facilitates the removal of fluid collections, reduces oedema R26 and accelerates healing by the formation of granulation tissue. It is a widely used technique that R27 gained popularity in the last decade. Is thought to be associated with the highest rates of delayed R28 primary fascial closure and the lowest mortality rates, yet this is only level IV evidence (7). R29 The latest modification is the combination of a mesh with a vacuum system (13) (14) (7). These R30 studies report a high fascial closure rate, however patients had to be taken into the operation R31 room every other day to change the vacuum system en tighten the mesh (14). Complications R32 like fistula formation occurred in about 5%. Both last mentioned procedures are also technically R33 demanding when ileo- or are present. R34 R35 The results after delayed primary fascial closure are unknown. Most studies choose the achieved R36 fascial closure rate as endpoint of their research. Morbidity and mortality is unknown as are R37 success rates and failures resulting in an incisional hernia. Follow-up in these studies is non- R38 R39 existing or very short.

52 | Chapter 4 Delayed fascial closure or ‘planned ventral hernia’? R1 When delayed primary closure of the fascia is not achieved, a ventral hernia exists. A split skin R2 graft is sometimes used to close the defect when granulation tissue is present. Some patients R3 R4 might want to have this hernia repaired. Several techniques are known to repair large incisional R5 hernias, such as a modified component separation technique, onlay and sublay procedures (15) R6 (16) all with the use of a synthetic mesh. The overall results of all surgical techniques are at R7 best moderate; recurrence rates up to 30% have been reported and complications like wound R8 infections frequently occur. R9 There is no study reporting the conservative treatment of the ‘planned ventral hernia’. Patients R10 might be fine once the abdominal wall has recovered and scar tissue might be strong enough to R11 keep the abdominal content into place. The use of bondage can also help these patients. R12 Quality of life (QOL) is a major endpoint in evaluating surgical techniques; however, only few R13 studies concerning the reconstruction of large ventral hernias included QOL questionnaires (17). 4 R14 QOL in patients with a large ventral hernia who are treated conservatively is unknown. R15 OAT is a known treatment in case of ACS and in damage control surgery. Patients who had an R16 open abdomen treatment are often compared with patients with large ventral hernias, while we R17 believe this is a different modality. R18 R19 Once the abdomen has been left open, the choice of a temporary abdominal closure depends on R20 the planned treatment strategy. When the surgeon aims for delayed fascial closure, the use of a R21 vacuum system is thought to give the highest chance of a successful closure. As a consequence, R22 patients have to undergo surgery every other day. If delayed primary fascial closure can be R23 obtained, the long-term results for developing an incisional hernia are unknown. R24 Frequent surgical intervention can be too invasive for critically ill and/or aged patients. In that R25 case achieving primary fascial closure is, or should not be the main goal and thus an absorbable R26 mesh is used. The mesh is easy to handle, allows for drainage and prevents the fascial edges to R27 shift too laterally. Using an absorbable mesh, a planned ventral hernia can be created, while the R28 patient recovers. R29 Patients with a planned ventral hernia may need a surgical correction, although conservative R30 management can be a good option to. Indications for surgical repair are usually pain, bowel R31 obstruction or aesthetic complaints. Conservative management has never been reported, so the R32 non-surgical treatment of large ventral hernias is unknown. Quality of life in this patient group R33 R34 has not been evaluated. In our study no difference was found between the two patients groups R35 according to patient satisfaction, pain and cosmetics. R36 R37 R38 R39

Open abdomen treatment: planned ventral hernia or delayed fascial closure? | 53 R1 Conclusion R2

R3 Level 1 and 2 evidence for OAT and the management after this treatment is non-existent. In R4 general, the indications for open abdomen treatment are known; i.e. ACS and damage control. R5 Once the fascia has been left open, the temporary coverage can be done using an absorbable R6 mesh, a vacuum system or a combination of both. R7 If OAT is necessary to prevent the patient from dying, the temporary closure should do the same. R8 R9 The way the abdomen is temporally closed, should not be dependent on the skills of the surgeon R10 on duty. It has to be a very easy procedure and should not have a large risk of complications R11 itself. The first goal should be survival of the severely ill patient. The use of an absorbable mesh R12 stapled to the skin or sewn at the fascia is a simple procedure and does not dependent on the R13 skills of the individual surgeon. Until evidence is available to advocate another procedure, we R14 therefore plea to keep it simple. If a patient survives, a reconstruction of the abdominal wall may R15 be necessary. However, a conservative treatment might be a good option to. For now options R16 should be discussed with the patient and treatment should be personalized. Further research is R17 necessary on how to manage patients with OAT. Survival and QOL should be major endpoints. R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

54 | Chapter 4 References R1 R2 1. Schein M, Ivatury R. Intra-abdominal hypertension and the abdominal compartment syndrome. Br J R3 Surg 1998, Aug;85(8):1027-8. R4 2. Stevens P. Vacuum-assisted closure of laparostomy wounds: A critical review of the literature. Int Wound J 2009, Aug;6(4):259-66. R5 3. Boele van Hensbroek P, Wind J, Dijkgraaf MG, Busch OR, Goslings JC, Carel Goslings J. Temporary R6 closure of the open abdomen: A systematic review on delayed primary fascial closure in patients with R7 an open abdomen. World J Surg 2009, Feb;33(2):199-207. R8 4. Miller PR, Meredith JW, Johnson JC, Chang MC. Prospective evaluation of vacuum-assisted fascial closure after open abdomen: Planned ventral hernia rate is substantially reduced. Ann Surg 2004, R9 May;239(5):608-14; discussion 614-6. R10 5. Tsuei BJ, Skinner JC, Bernard AC, Kearney PA, Boulanger BR. The open peritoneal cavity: Etiology R11 correlates with the likelihood of fascial closure. Am Surg 2004, Jul;70(7):652-6. R12 6. Anderson O, Putnis A, Bhardwaj R, Ho-Asjoe M, Carapeti E, Williams AB, George ML. Short- and long- term outcome of laparostomy following intra-abdominal sepsis. Colorectal Dis 2011, Feb;13(2):e20-32. R13 7. Acosta S, Bjarnason T, Petersson U, Pålsson B, Wanhainen A, Svensson M, et al. Multicentre prospective 4 R14 study of fascial closure rate after open abdomen with vacuum and mesh-mediated fascial traction. Br R15 J Surg 2011, Jan 14. R16 8. Prichayudh S, Sriussadaporn S, Samorn P, Pak-Art R, Sriussadaporn S, Kritayakirana K, Capin A. Management of open abdomen with an absorbable mesh closure. Surg Today 2011, Jan;41(1):72-8. R17 9. Fieger AJ, Schwatlo F, Mündel DF, Schenk M, Hemminger F, Kirchdorfer B, et al. [Abdominal vacuum R18 therapy for the open abdomen - a retrospective analysis of 82 consecutive patients]. Zentralbl Chir R19 2011, Feb;136(1):56-60. R20 10. Caro A, Olona C, Jiménez A, Vadillo J, Feliu F, Vicente V. Treatment of the open abdomen with topical negative pressure therapy: A retrospective study of 46 cases. Int Wound J 2011, Jun;8(3):274-9. R21 11. Mayberry JC, Burgess EA, Goldman RK, Pearson TE, Brand D, Mullins RJ. Enterocutaneous fistula and R22 ventral hernia after absorbable mesh prosthesis closure for trauma: The plain truth. J Trauma 2004, R23 Jul;57(1):157-62; discussion 163-3. R24 12. Padalino P, Dionigi G, Minoja G, Carcano G, Rovera F, Boni L, Dionigi R. Fascia-to-fascia closure with abdominal topical negative pressure for severe abdominal infections: Preliminary results in a department R25 of general surgery and intensive care unit. Surg Infect (Larchmt) 2010, Dec;11(6):523-8. R26 13. Seternes A, Myhre HO, Dahl T. Early results after treatment of open abdomen after aortic surgery with R27 mesh traction and vacuum-assisted wound closure. Eur J Vasc Endovasc Surg 2010, Jul;40(1):60-4. 14. Petersson U, Acosta S, Björck M. Vacuum-assisted wound closure and mesh-mediated fascial traction- R28 -a novel technique for late closure of the open abdomen. World J Surg 2007, Nov;31(11):2133-7. R29 15. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. Open surgical procedures for incisional hernias. R30 Cochrane Database Syst Rev 2008(3):CD006438. R31 16. Poelman MM, Langenhorst BL, Schellekens JF, Schreurs WH. Modified onlay technique for the repair of the more complicated incisional hernias: Single-centre evaluation of a large cohort. Hernia 2010, R32 Aug;14(4):369-74. R33 17. Zarzaur BL, DiCocco JM, Shahan CP, Emmett K, Magnotti LJ, Croce MA, et al. Quality of life after R34 abdominal wall reconstruction following open abdomen. J Trauma 2011, Feb;70(2):285-91. R35 R36 R37 R38 R39

Open abdomen treatment: planned ventral hernia or delayed fascial closure? | 55

Chapter 5

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open surgery and

laparoscopic surgery for incisional hernia repair

Poelman M Apers J van den Brand H Cense H Consten E Deelder J Dwars B van Geloven N de Lange E Lange J Simmermacher R Simons M Sonneveld E Schreurs H Bonjer J

BMC Surgery 2013 13:18 (7 June 2013) R1 Abstract R2

R3 Background Annually approximately 100.000 patients undergo a laparotomy in the Netherlands. R4 About 15,000 of these patients will develop an incisional hernia. Both open and laparoscopic R5 surgical repair have been proven to be safe. However, the most effective treatment of incisional R6 hernias remains unclear. This study, the ‘INCH-trial’, comparing cost-effectiveness of open and R7 laparoscopic incisional hernia repair, is therefore needed. R8 R9 R10 Methods / Design A randomized multi-center clinical trial comparing cost-effectiveness of open R11 and laparoscopic repair of incisional hernias. Patients with a symptomatic incisional hernia, R12 eligible for laparoscopic and open incisional hernia repair. Only surgeons, experienced in both R13 open and laparoscopic incisional hernia repair, will participate in the INCH trial. During incisional R14 hernia repair, a mesh is placed under or on top of the fascia, with a minimal overlap of 5 cm. R15 Primary endpoint is length of hospital stay after an incisional hernia repair. Secondary endpoints R16 are time to full recovery within three months after index surgery, post-operative complications, R17 recurrences, mortality and quality of life. R18 Our hypothesis is that laparoscopic incisional hernia repair comes with a significant shorter R19 hospital stay compared to open incisional hernia repair. A difference of two days is considered R20 significant. One-hundred-and-thirty-five patients are enrolled in each treatment arm. The R21 economic evaluation will be performed from a societal perspective. Primary outcomes are costs R22 per patient related to time-to-recovery and quality of life. R23 R24 The main goal of the trial is to establish whether laparoscopic incisional hernia repair is superior R25 to conventional open incisional hernia repair in terms of cost-effectiveness. This is measured R26 through length of hospital stay and quality of life. Secondary endpoints are re-operation rate due R27 to post-operative complications or recurrences, mortality and quality of life. R28 R29 Discussion The difference in time to full recovery between the two treatment strategies is thought R30 to be in favor of the laparoscopic incisional hernia repair. Laparoscopic incisional hernia repair is R31 therefore thought to be a more cost-effective approach. R32 R33 R34 R35 R36 R37 R38 R39

58 | Chapter 5 Introduction R1 R2

Incisional hernias are defects of the fascia of the abdominal wall, covered by skin, which can R3 R4 develop after abdominal surgery. Bulging through the scar is visible and palpable when patients are R5 standing or coughing (1-2). These hernias occur in at least 15% of patients after open abdominal R6 surgery within ten years after surgery. Incisional hernias may be asymptomatic, but frequently R7 they cause pain and give aesthetic complaints. They can also cause serious complications like R8 strangulation of the bowel. The quality of life in these patients as well as their chances for R9 employment is reduced (2). R10 R11 Pre-disposing factors to get an incisional hernia are obesity, which is increasing rapidly in the R12 Western world, and a post-operative surgical site infection (3). There are no differences between R13 men and women in developing an incisional hernia. Ethnical differences are not known. The R14 pathogenesis of incisional hernias is complex; altered collagen metabolism and extra-cellular R15 matrix disorders causing wound-healing disorders have been found in patients who developed R16 incisional hernias (4). R17 5 R18 R19 A population based study showed a 3,7% yearly increase in the incidence of incisional hernia repair R20 per 10.000 people (5) in the United States. Since obesity plays an important role in developing R21 an incisional hernia and is an increasing problem in the Netherlands, we expect the incidence of R22 incisional hernias to increase in the Netherlands as well. Mean age at time of the surgical repair is R23 58 years old; mean SD 15 years (6). The majority of these patients will have to go back to work. R24 R25 Eighty per cent of the patients with an incisional hernia undergo surgical repair (5). The R26 morbidity of open incisional hernia repair is more than 20% involving recurrence and mesh R27 infection. Laparoscopic surgery tends to be safe and is associated with less infections and shorter R28 hospitalization. It is highly feasible in obese patients, because of a good exposure of the incisional R29 hernia. However, the surgical procedure can be difficult and the operating time might be longer. R30 Up till now it is not clear what is the best treatment strategy for incisional hernias. The potential R31 benefits of a more defined treatment strategy includes a shorter hospital admission, cost reduction R32 and less post-operative complications. R33 R34 R35 Two recent meta-analysis (7,8) state that laparoscopic repair is at least as effective and might be R36 superior to the open approach in a number of outcomes. Total hospital stay was shorter and less R37 post-operative complications were seen. The largest study in the meta-analysis (8) has several R38 R39

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open | 59 R1 shortcomings; randomization is not listed and there was no sample size calculation. Most studies R2 only provide short-term follow-up evaluation and cost-effectiveness is not evaluated. This study, R3 comparing the cost-effectiveness of open and laparoscopic incisional hernia repair, is therefore R4 needed. R5 Criteria to recommend a surgical repair should be stated and the natural course of an incisional R6 hernia should be examined. R7 R8 R9 This is a multi-centre study with surgeons who are experienced in open as well as laparoscopic R10 surgery. The study group exists of dedicated laparoscopic surgeons, committed to improve hernia- R11 care. First, we want to know if laparoscopic repair is more effective than open repair. The future R12 of this study will allow evidence-based change of practice. R13 R14 R15 Methods / Design R16 R17 A randomized multi-centre trial comparing the cost-effectiveness of two surgical techniques for R18 the repair of incisional hernias: laparoscopic vs. conventional open repair. R19 R20 Inclusion criteria: R21 The following patients will be eligible for the randomization to either open or laparoscopic repair: R22 Adult patients who are referred to the surgical clinic for assessment of an incisional hernia, either R23 R24 primary or recurrent. Imaging of the abdomen will only be done when it is unclear whether an R25 incisional hernia is present. The need for surgery will be determined; pain, severe discomfort R26 and episodes of visceral incarceration are indications for surgery. Only symptomatic patients will R27 get a surgical correction of the incisional hernia. Patients whose incisional hernia is suitable for R28 laparoscopic repair are included in the trial, this decision is at the discretion of the surgeon. R29 After consenting to the study, the patient will be randomized to either open or laparoscopic R30 repair. Patients who are excluded or who don’t want to participate will be registered. (figure 1; R31 flowchart). R32 R33 R34 R35 R36 R37 R38 R39

60 | Chapter 5 R1 R2 R3 patients with an incisional hernia R4 R5 R6 R7

symptomatic asymptomatic R8 R9 R10 R11 excluded patients. R12 elegible for register patient in register patient in randomisation the database the databse R13 R14 R15 R16 laparoscopic open incisional incisional hernia R17 hernia repair repair R18 Figure 1: flowchart. 5 R19 R20 Exclusion criteria: R21 1. Pregnancy R22 2. Age less than 18 years old 18 R23 3. Abdominal ostomy R24 4. History of open abdomen treatment R25 5. Mentally or cognitively unable to be consented R26 6. A life expectancy of less than one year R27 7. Immune-compromised patients R28 8. ASA>3 (ASA: scoring system of the American Society of Anaesthesiologists) R29 R30 Treatment: R31 Patients will be randomized, using a computer-program, to one of the following surgical R32 approaches: R33 R34 I) Open repair of the incisional hernia: the employed open technique is at the discretion of the R35 participating surgeon. There is no evidence, which open technique, is best; bridging as well as R36 augmenting techniques might be used. Onlay, sublay as well as CST technique are allowed as R37 long as a mesh is used. An overlap of at least 5cm of the mesh over the fascia is preferable. R38 R39

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open | 61 R1 II) Laparoscopic repair of incisional hernias will entail employment of mesh that is placed R2 subfascially with a minimal overlap of 5cm. Choice and fixation of the mesh is at the discretion R3 of the surgical team. During laparoscopic surgery a photograph will be taken of the hernia defect R4 before and after the correction is done. When laparoscopic repair is not successfully achieved R5 or complications occur, the surgeon may decide to change to the open surgical procedure (i.e. R6 conversion); this is common practice in laparoscopic surgery. R7 In each approach, the use of a mesh is preferable, as this has shown to reduce the recurrence- R8 R9 rate (9). Every detail of the technique should be described. Dutch hernia experts will perform the R10 surgical corrections. R11 R12 Case Record Form: R13 At first presentation in the outpatient clinics: age/ sex/ co-morbidity/ pre-illness/ working-social R14 activities/ surgical history/ symptoms of the incisional hernia/ classification of the incisional hernia: R15 The European Hernia Society (EHS) tried to categorize incisional hernias, in order to be able to R16 compare different scientific incisional hernia research (10). A classification system of abdominal R17 wall hernias was formulated (figure 2). This classification will be used in the INCH-trial. R18 Postoperatively: open or laparoscopic/ length of the scar/ duration of surgery/ type of mesh used/ R19 size of the mesh/ type of mesh fixation/ presence of bleeding/ accidental bowel lesion/ use of R20 tubes/ use of per-operative antibiotics/ possible re-operation. R21 Inpatient: daily VAS score/ use of analgesics/ length of hospital stay/ morbidity/ mortality/ QOL at R22 two days post-surgery. R23 R24 During Follow-up at 2 weeks and 3 months: healthcare and lost productivity costs/ QOL at 2 R25 weeks and 3 months post-surgery will be measured through the Short Form 36 and the Carolina R26 Comfort Scale/ time to return to work/ recurrence/ pain/ wound infection/ patient satisfaction/ R27 other morbidity. R28 During long-term follow-up at 1, 3 and 5 years: Recurrence/ pain/ wound infection/ patient R29 satisfaction/ other morbidity. R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

62 | Chapter 5 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15

R16 R17 5 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35

R36

Figure 2 R37 R38 R39

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open | 63

54 R1 Primary outcomes R2 --Length of hospital stay. This is the time until discharge. A patient can be discharged when he/ R3 she is able to move normally, tolerate a normal diet and has a VAS painscore< 5 without the use R4 of opiates. R5 --Quality of life measures through SF-36 and CCS. R6 R7 Secondary endpoints R8 R9 -Re-operation rate for recurrence or complications of the incisional hernia repair. The analysis R10 will be continued after the cost-effectiveness study has ended, a longer follow-up is needed to R11 examine the recurrence-rate. R12 -28 days post surgery morbidity and mortality, R13 -Shape of the abdomen: a digital photograph of the abdomen using raster-stereography will be R14 taken pre- and post-operatively to analyse the change in the abdominal shape. R15 -Total mean costs will be related to the following effect measures in the cost-effectiveness R16 analyses: R17 1) Time to full recovery R18 2) Quality-adjusted life-years (QALYs) based on the SF-36D(11) R19 R20 Intention to treat analysis will be performed. Blinding is impossible as the surgical difference is R21 visible from the outside. R22 R23 R24 Economic evaluation R25 The aim of the economic evaluation is to describe the costs of laparoscopic and open repair of R26 incisional hernias, and to relate the costs to the clinical effects of the treatments. The time horizon R27 of the economic evaluation is 3 months. A societal perspective is chosen for this economic R28 evaluation. For the measurement and valuation of the costs the Dutch costing guidelines will be R29 used (12). R30 R31 Cost measurement and valuation Health care utilization will be measured using hospital data R32 and cost diaries during hospitalization and after 2 weeks and 3 months of follow-up. Health care R33 costs include costs of the operation, hospital stay, medical supplies, additional examinations (CT, R34 X-ray, laboratory, etcetera), medication, GP care, emergency visits and ambulatory hospital care. R35 Absenteeism from paid and unpaid work and presenteeism at baseline and after 2 weeks and 3 R36 months of follow-up will also be measured. R37 R38 R39

64 | Chapter 5 For the valuation of health care utilization standard prices published in the Dutch costing R1 guidelines will be used (12). Medication use will be valued using prices of the Royal Dutch R2 Society for Pharmacy. A detailed cost price calculation will be performed to estimate the costs of R3 R4 laparoscopic and open repair of incisional hernias. R5 R6 Analysis of cost-effectiveness R7 The analysis will be done according to the intention-to-treat principle. Missing cost and effect R8 data will be imputed using multiple imputations according to the MICE algorithm developed R9 by Van Buuren (13). Costs typically have a highly skewed distribution. Policy makers want to R10 have information on the difference in mean total costs between the two treatment-groups to R11 be able to estimate the total health care budget needed for a specific condition (14). Therefore, R12 bias-corrected and accelerated bootstrapping with 5000 replications will be used to calculate R13 95% confidence intervals around the mean difference in total costs between the treatment R14 groups. Incremental cost-effectiveness ratios (ICERs) will be calculated by dividing the difference R15 in mean total costs between the treatment groups by the difference in mean effects between the R16 treatment groups. Bootstrapping will be used to estimate the uncertainty surrounding the ICERs, R17 which will be graphically presented on cost-effectiveness planes. Cost-effectiveness acceptability 5 R18 R19 curves and net monetary benefits will also be calculated. Cost-effectiveness acceptability curves R20 show the probability that collaborative care is cost-effective in comparison with usual care for a R21 range of different ceiling ratios thereby showing decision uncertainty (15). R22 R23 The baseline data of both treatment groups will be described and 95% confidence intervals will R24 be calculated. Additional as-treated analyses will be done, because patients who were planned R25 to have a laparoscopic repair might have had an open correction and vice versa. Differences in R26 primary and secondary endpoints between the two treatment groups will be calculated as well R27 as their 95% confidence intervals. Student’s t tests, Chi square tests or Fisher exact tests will R28 be applied where appropriate. The risk of re-operation will also be studied by application of a R29 multiple logistic regression model. R30 R31 Statistics R32 Sample size calculation: This is a superiority design: Our hypothesis is that length of hospital stay R33 R34 is shorter after incisional hernia repair, and therefore the laparoscopic approach will be superior R35 in terms of cost-effectiveness. Statistics are based on an average hospital stay of 2 days (SD 5) R36 after laparoscopic repair (8). The outcome is considered superior if there is a difference in hospital R37 stay of more than 2 days. Therefore, 135 patients in each treatment arm are needed (alpha R38 R39

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open | 65 R1 0,05/ power 0,9) (16). Loss to follow-up may occur; we will therefore aim for an inclusion of 300 R2 patients. R3 R4 Randomisation will be performed through a computer-guided system. A stratified block- R5 randomisation will be used per centre. The randomisation code will be noted on the patients file. R6 Peritonitis carcinomatosa, unplanned surgical procedures for pathology that was not discovered R7 during pre-operative analysis, absence of an incisional hernia are reasons for post-randomization R8 R9 exclusion. R10 R11 Feasibility R12 Twelve hospitals, both university medical centres and community hospitals, will participate in this R13 trial. The study group consists of hernia experts from these 12 centres, who frequently perform R14 laparoscopic as well as open hernia surgery. These hospitals perform about 20-30 incisional R15 hernia corrections a year, and aim for an inclusion of 10-15 patients each year. R16 We aim for 125 patients per year, hence 12-13 inclusions every month. This is highly feasible, R17 because these 12 centres together perform over 300 incisional hernia repairs annually. We aim R18 for participation of more centres along the way, but only experienced laparoscopic surgeons can R19 participate. R20 R21 Time schedule R22 Study preparation and formation of a core study group is already in progress. Initiation of the R23 R24 INCH-trial around 1-8-2012 after METC permission is obtained in each hospital. We aim for an R25 inclusion rate of 10-15 patients per month. About 28 months are needed to include the amount R26 of patients needed to calculate the difference in length of hospital stay. After this period the trial R27 will continue; to meet the secondary end-point a longer follow-up period is needed. The follow- R28 up will be continued at 3 and 5 year after index surgery. Patients who don’t want to participate R29 and patient who are excluded will be registered. R30 R31 Ethical approval and safety monitoring R32 According to the ‘Good Clinical Practice’ rules, ethical approval has been asked and obtained R33 from our Medical Ethical Board (METC). This independent board will supervise the trail and make R34 decisions about all possible changes in the study through amendments. The board will also R35 monitor the possible complications. R36 R37 R38 R39

66 | Chapter 5 No experimental surgery is performed; all the surgical techniques used are already part of our R1 daily practice. All hospitals record (post-operative) morbidity according to guidelines of the Dutch R2 Society of Surgeons. Adverse effects will be registered and told to the METC. R3 R4 R5 SAE’s All individual Serious Adverse Events (SAE’s) will be registered and reported to the CCMO. R6 Sepsis and possible re-operation due to a missed bowel perforation after laparoscopic incisional R7 hernia repair, as well as death in the direct post-operative phase will be reported within 7 days. R8 Permission has been obtained for ‘line listing’ for all other individual SAE’s; the METC permits to R9 report all other events once every 6 months. R10 R11 Criteria for participating centres Participating surgeons have already performed at least 50 open R12 and 50 laparoscopic incisional hernia repairs. They will hand over an unedited recording of a R13 laparoscopic incisional hernia repair of their own. The principle investigators will review their R14 recordings. Guidelines to perform a safe laparoscopic procedure will be made. Participating R15 surgeons have to follow the guidelines. R16 R17

Goal 5 R18 R19 The goal of the trial is to establish whether laparoscopic incisional hernia repair is superior to R20 conventional open incisional hernia repair in terms of cost-effectiveness. This is measured through R21 length of hospital stay and quality of life. Secondary endpoints are re-operation-rate (due to R22 complications or recurrence), morbidity, mortality and shape of the abdomen. R23 In current surgical practice there is on going discussion about the possible benefits of laparoscopic R24 incisional hernia surgery. Scientific evidence is lacking to determine whether laparoscopic R25 correction is superior to conventional open techniques in terms of cost-effectiveness. R26 R27 R28 Discussion R29 R30 The difference in time to full recovery between the two treatment strategies is thought to be in R31 favor of the laparoscopic incisional hernia repair. Laparoscopic incisional hernia repair is therefore R32 thought to be a more cost-effective approach. R33 R34 R35 R36 R37 R38 R39

The INCH-Trial: a multicenter randomized controlled trial comparing the efficacy of conventional open | 67 R1 References R2 R3 1. Cassar K, Munro A. Surgical treatment of incisional hernia. Br J Surg 2002; 89: 534-45. R4 2. Den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. Open surgical procedures for incisional hernias. Cochrane Database Syst Rev 2008 jul 16;(3):CD006438. R5 3. Llaguna OH, Avgerinos DV, Lugo JZ, Matatov T, Abbadessa B, Martz JE, Leitman IM. Incidence and R6 risk factors for the development of incisional hernia following elective laparoscopic versus open colon R7 resections. Am J surg aug 2010 Aug;(200)2: 265-269. R8 4. Rosch R, Junge K, Knops M, Lynen P, Klinge U, Schumpelick V. Analysis of collagen-interacting proteins in patients with incisional hernias. Ach surg 2003 vol 387;427-432. R9 5. Nieuwenhuizen J, Kleinrensink GJ, Hop WC, Jeekel J, Lange JF. Indications for incisional hernia repair: R10 an international questionnaire among hernia surgeons. Hernia 2008; 12: 223-5. R11 6. Flum DR, Horvath K, Koepsell T. Have outcomes of incisional hernia repair improved with time? Annals R12 of surgery 2003; vol 237, No 1, 129-135.10. 7. Forbes SS, Eskicioglu C, McLeod RS, Okrainec A. Meta-analysis of randomized controlled trials R13 comparing open and laparoscopic ventral incisional hernia repair with mesh. Br J Surg 2009; 96: 851- R14 858. R15 8. Sajid MS, Bokhari SA, Mallick AS, Cheek S, Baig MK. Laparoscopic versus open repair of incisional/ R16 ventral hernia: a meta-anaysis. Am J Surg 2009: 197: 64-72. 9. Luijendijk RW, Hop WCJ, van den Tol MP, de Lange DCD, Braaksma MMJ, IJzermans JNM, Boelhouwer R17 RU, de Vries BC, Salu MKM, Wereldsma JCJ, Bruijninckx DCMA, Jeekel J. A comparison of suture repair R18 with mesh repair for incisional hernia. N Engl J Med 2000; 343: 392-8. R19 10. Muysoms FE, Miserez M, Berrevoet F, Campanelli G, Champault GG, Chelala E, Dietz UA, Eker HH, El R20 Nakadi I, et al. Classification of primary and incisional abdominal wall hernias. Hernia 2009;13:407– 414.11. R21 11. Brazier J, Robert J, Deverill M. The estimation of a preference-based measure of health from the SF-36. R22 J Health Econ 2002 Mar;21(2):271-92. R23 12. Oostenbrink, J. B., Bouwmans, C. A. M., Koopmanschap, M. A., and Rutten, F. F. H. Handleiding R24 voor kostenonderzoek: Methoden en standaard kostprijzen voor economische evaluaties in de gezondheidszorg. Geactualiseerdeversie 2004 [Handbook for cost studies: methods and standard costs R25 for economic evaluation in health care. Updatedversion 2004. Den Haag, The Netherlands: College R26 voor Zorgverzekeringen; 2004. R27 13. vanBuuren, S. and Oudshoorn, C. G. M. Multivariate Imputation by Chained Equations. Leiden: TNO;2000. R28 14. Thompson SG, Barber JA. How should cost data in pragmatic randomised trials be analysed? BMJ 2000 R29 Apr 29;320(7243):1197-200. R30 15. Fenwick E, Byford S. A guide to cost-effectiveness acceptability curves. Br J Psychiatry 2005 R31 Aug;187:106-8. 16. Dupont WD, Plummer WD. Power and Sample Size Calculations forStudies Involving Linear Regression. R32 Controlled Clinical Trials 1998; 19:589-601. R33 R34 R35 R36 R37 R38 R39

68 | Chapter 5 Chapter 6

Comparison of the Dutch and English version of the

Carolinas Comfort Scale; a specific quality of life- questionnaire for abdominal hernia repairs with mesh

K Nielsen MM Poelman FM den Bakker HJ Bonjer WH Schreurs

Hernia 2013 Oct 29 R1 Abstract R2

R3 Purpose Repair of abdominal wall hernias with mesh is one of the most common procedures in R4 general surgery. The introduction of hernia repair with mesh has lowered recurrence rates and R5 shifted the focus to quality of life after surgery, raising the need for a specific tool measuring R6 quality of life. The Carolinas Comfort Scale (CCS) is a questionnaire designed specifically for R7 patients having hernia repair with mesh. The aim of this study is to validate the Dutch CCS and R8 R9 to compare it to the generic short-form-36 (SF-36). R10 R11 Methods The CCS questionnaire was translated into Dutch. Patients undergoing mesh hernia R12 repair between April 2010 and December 2011 completed the CCS, the SF-36 and 4 questions R13 comparing these two questionnaires in the first week after surgery. After three weeks, the CCS R14 was repeated. Correlations between the two surveys were calculated using the Spearman’ s rank R15 correlation test with a 95% confidence interval to determine validity. R16 R17 Results The response rate was 60.3% (100/168). The CCS showed excellent reliability R18 with a Crohnbach’s α of 0.948. Significant correlation existed between the CCS and the R19 domains physical functioning, bodily pain, role physical, vitality and social functioning of R20 the SF-36. Seventy-nine percent of the patients preferred the CCS to the SF-36, and 83% R21 considered the CCS a better reflection of their quality of life after hernia repair with mesh. R22 R23 R24 Conclusion The Dutch CCS appears a valid and clinically relevant tool for assessing quality of life R25 after repair of abdominal wall hernia with mesh. R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

70 | Chapter 6 Introduction R1 R2

Surgical repair of inguinal, umbilical and incisional hernias is the most common procedure in R3 R4 general surgery. Annually, more than 20 million groin hernias (inguinal and femoral) are repaired R5 worldwide, with a respective lifetime risk of 27% and 3% in men and women (1;2). Umbilical R6 hernias account for 10% of all primary hernias (3). Incisional hernias occur in 20% of patients R7 within 10 years after abdominal surgery (4). About 80% of these patients with incisional hernias R8 require surgical repair(5). R9 Patients with hernias of the abdominal wall seek medical care for various reasons, discomfort R10 being the most important (6-8). Also, patients have notice a lump in the groin, umbilicus R11 or at a scar after abdominal surgery. Surgical repair is advised depending on the size of the R12 hernia, age, co-morbidities, the living proximity to a medical centre and personal preference R13 of the patient. The compelling reason for surgery in these asymptomatic patients is prevention R14 of incarceration of visceral contents in the hernia. Particularly in the elderly, a conservative R15 approach, coined watchful waiting, is evaluated considering that the risk of incarceration R16 is low: less than 1% in patients with asymptomatic groin hernias (9-11). For umbilical and R17 incisional hernias this risk is still to be determined. A small group of patients with hernias of the R18 R19 abdominal wall presents with tenderness of pain. These patients are usually managed surgically. R20 Surgery of abdominal wall hernias has been hampered for almost a century by high recurrence R21 rates. These recurrences have overshadowed other important aspects of surgery for hernias such 6 R22 as chronic pain and loss of compliance of the abdominal wall. R23 The introduction of ‘tension-free’ repairs, employing meshes, by Lichtenstein in the 1970’s has R24 changed the surgical approach to hernias greatly and lowered recurrence rates significantly (12- R25 14). Traditionally, tension repairs of inguinal hernias were associated with recurrence rates as R26 high as 25 %. These rates decreased to less than 5 % upon use of mesh (15-18). Chronic pain R27 after inguinal hernia repair was rarely reported in the past but occurs frequently in up to 20 % R28 of all patients within the first year after surgery subsiding to less than 5 % at 5 years (4;19-21). R29 Management of pain in these patients has proven very complex. R30 Umbilical hernias are still repaired preferentially without mesh which is, however, associated with R31 high recurrence rates of up to 40% (22). The value of mesh in umbilical hernia surgery is currently R32 under review. R33 R34 Incisional hernias, which occur in 15 to 20 % of patients after traditional open surgery, form R35 a distinct entity of abdominal wall hernias (23). Patients with incisional hernias present with a R36 swelling at the site of previous surgery. Pain is relatively rare in these patients. Incisional hernias R37 over 3 centimetres in diameter require repair with mesh. Although the use of mesh has reduced R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 71 R1 the rate of recurrences, patients continue to experience recurrent hernias in 10 to 15 % after R2 repair with mesh (2;9;12;23). Initially, heavy weight meshes such as small pore polypropylene R3 were utilized. These meshes are rigid and affect the compliance of the abdominal wall. In addition, R4 bowels tend to adhere to polypropylene meshes resulting in adhesive bowel obstruction and, in R5 rare instances, fistulas to the gut. R6 Introduction of mesh in surgery for hernias of the abdominal wall has shifted the focus from R7 recurrent hernias to quality of life. While the rate of recurrence can be determined accurately, R8 R9 measuring quality of life is more demanding. Various generic tools such as Short Form-36 (SF-36) R10 exist but have proven not very valuable to quantify outcomes of hernia surgery (24-26). R11 To measure the influence of a specific surgical intervention, there is a need for disease specific R12 instruments with a focus on particular health outcomes. The Carolinas Comfort Scale has been R13 developed to evaluate the sensation of the mesh, pain and movement limitations after hernia R14 surgery with mesh in different aspects of daily life (6). Experience with this tool, which is currently R15 only available in English, is limited (6;27;28). The objective of this study is to translate and validate R16 the Carolinas Comfort Scale in Dutch and to assess the value of the Dutch version of the Carolinas R17 Comfort Scale compared to the SF-36 in a group of patients with hernias of the abdominal wall. R18 R19 R20 Material and Methods R21 R22 The Medical Centre Alkmaar local ethics board approved of this study. Patients who had R23 R24 undergone surgical abdominal hernia repair with a mesh between April 2010 and December R25 2011 at the Medical Centre Alkmaar participated in this study after gaining informed consent. R26 Inclusion criteria were surgical repair of inguinal, femoral, incisional or umbilical hernias with a R27 mesh within previous six months, being 18 years of age or older and able to read and understand R28 the Dutch language. Exclusion criteria were a life expectancy of less than 24 months and immune R29 suppression therapy within two weeks before surgery. R30 The English version of the Carolinas Comfort Scale was translated into Dutch (Appendix). The R31 translation was produced by a forward-backward procedure. R32 While patients were admitted in the hospital, they were asked by the study coordinator to R33 participate in the study. All patients were asked to complete the SF-36 and the Carolinas Comfort R34 Scale at home, without the presence of an interviewer, 4-7 days after surgery. A self addressed R35 stamped envelope was added to return completed forms. In this study we assess construct validity R36 by comparing the Carolinas Comfort Scale to a well-known validated quality of life questionnaire, R37 the SF-36. Construct validity refers to whether the new test actually measures the theoretical R38 R39

72 | Chapter 6 construct that it purports to measure. Subsequently, all patients were asked to complete the R1 Carolinas Comfort Scale again three weeks after completing the first survey to determine test- R2 retest reliability. The test was mailed to the home address, including the self addressed and R3 R4 stamped envelope, so all patients could complete the test at home without an interviewer present. R5 R6 Questionnaires The SF-36 is a multi-purpose short form health survey containing 36 questions R7 about 8 domains of quality of life: physical functioning, role-physical, bodily pain, general health, R8 vitality, social functioning, role-emotional and mental health. These domains are scored on a scale R9 of 0-100, with the maximal score representing optimal functioning (24). R10 The Carolinas Comfort Scale (table 1) is a 23 item questionnaire that measures severity of pain, R11 sensation and movement limitations from the mesh in eight different categories of normal daily R12 life: lying down, bending over, sitting up, activities of daily living, coughing or taking a deep R13 breath, walking, climbing the stairs and physical or sport exercise. The score is based on a scale R14 0-115 with 0 being the best possible level of functioning (6). R15 Four questions were added to compare the Carolinas Comfort Scale and the SF-36; R16 1. Which questionnaire did you like best? R17 1. Which questionnaire is easier to understand? R18 R19 2. Which questionnaire is more reflective of the problems you have with your mesh? R20 3. Given the choice, which questionnaire would you prefer? R21 6 R22 Statistical analyses R23 To determine the construct validity of the test, the total score of the Carolinas Comfort Scale was R24 compared to all domains of the SF-36 using Spearman’s rank correlation coefficient test. R25 Cronbach’s α was used to measure reliability, or internal consistency, of the test score. This test is R26 commonly used to determine overall correlation between items in a scale. An outcome of 0.7 or R27 more is considered acceptable. In addition, we conducted a factor analysis based on all questions R28 of the Carolinas Comfort Scale. Test-retest reliability was estimated by Spearman’s correlation R29 coefficients of two assessments completed three weeks apart from each other. A principal R30 component analysis was performed to study if the Carolina’s Comfort Scale is unidimensional. R31 All data were analyzed using SPSS version 15.0 (Chicago, SPSS Inc). The significance level was R32 set to 0.05. R33 R34 R35 R36 R37 R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 73 Table 1: Carolinas Comfort Scale* R1 0 = No symptoms; 1 = Mild but not bothersome symptoms; 2 = Mild and bothersome symptoms; 3 = R2 Moderate and/or daily symptoms; 4 = Severe symptoms; 5 = Disabling symptoms R3 1. While lying down, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R4 Pain 0 1 2 3 4 5 n/a 2. While bending over, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R5 Pain 0 1 2 3 4 5 n/a R6 Movement limitations 0 1 2 3 4 5 n/a R7 3. While sitting up, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R8 Pain 0 1 2 3 4 5 n/a Movement limitations 0 1 2 3 4 5 n/a R9 4. While performing activities of daily life, do you Sensation on the mesh 0 1 2 3 4 5 n/a R10 have R11 Pain 0 1 2 3 4 5 n/a R12 Movement limitations 0 1 2 3 4 5 n/a R13 5. While coughing or deep breathing, do you have Sensation on the mesh 0 1 2 3 4 5 n/a Pain 0 1 2 3 4 5 n/a R14 Movement limitations 0 1 2 3 4 5 n/a R15 6. While walking, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R16 Pain 0 1 2 3 4 5 n/a R17 Movement limitations 0 1 2 3 4 5 n/a 7. While walking up the stairs, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R18 Pain 0 1 2 3 4 5 n/a R19 Movement limitations 0 1 2 3 4 5 n/a R20 8. While exercising, do you have Sensation on the mesh 0 1 2 3 4 5 n/a R21 Pain 0 1 2 3 4 5 n/a Movement limitations 0 1 2 3 4 5 n/a R22 R23 * The Carolinas Comfort Scale was created by and is licensed from the Division of Gastrointestinal and Minimally Invasive Surgery of Carolinas Medical Center in Charlotte, North Carolina. R24 R25 R26 R27 Results R28 R29 In total, 166 patients were asked to participate in this study. One hundred patients returned R30 completed questionnaires, 95 males and 5 females. The response rate was 60.3%. Ninety percent R31 of the patients had an inguinal hernia, 6% had an incisional hernia, 3% an umbilical hernia and R32 1% a . R33 R34 R35 R36 R37 R38 R39

74 | Chapter 6 Acceptability R1 Of the 100 patients who returned the Carolinas Comfort Scale the first time there were no R2 missing items in question 1-7. In 65% of the returned forms patients scored either n/a R3 R4 or there were missing items in the category ‘physical exercise and sports’ and therefore this R5 question was left out in the analysis. Four per cent of the SF-36 had at least one missing item. R6 When comparing the two questionnaires, 75% preferred the Carolinas Comfort Scale and 79% R7 thought the Carolinas Comfort Scale was easier to understand (table 2). Eighty-three per cent of R8 the patients thought the Carolinas Comfort Scale to be more specific for their situation and 79% R9 would rather fill out the Carolinas Comfort Scale than the SF-36. R10 R11 Table 2: Outcome questionnaire comparing CCS and SF 36 R12 CCS SF36 R13 Which questionnaire did you like best? 75% 25% R14 Which questionnaire is easier to understand? 79% 21% Which questionnaire is more reflective of the problems you have with your mesh? 83% 17% R15 Given the choice, which questionnaire would you rather fill out? 79% 21% R16 R17 R18 Table 3: Test-retest validity (n=92) Domain Correlation coefficient 95% Confidence interval P value R19 Laying down 0.286 0.071-0.523 < 0.01 R20 0.445 0.204-0.613 < 0.01 R21 Bending over 0.288 0.083-0.515 < 0.01 6 R22 0.529 0.300-0.684 < 0.01 0.563 0.428-0.702 < 0.01 R23 Sitting 0.331 0.115-0.566 < 0.01 R24 0.372 0.166-0.596 < 0.01 R25 0.515 0.322-0.641 < 0.01 R26 Activities of daily living 0.456 0.269-0.618 < 0.01 0.531 0.332-0.690 < 0.01 R27 0.537 0.365-0.688 < 0.01 R28 Coughing or deep breathing 0.247 0.026-0.447 0.017 R29 0.392 0.159-0.595 < 0.01 R30 0.333 0.139-0.488 < 0.01 R31 Walking 0.225 0.037-0.422 0.03 0.438 0.263-0.575 < 0.01 R32 0.481 0.323-0.621 < 0.01 R33 Walking stairs 0.373 0.149-0.546 < 0.01 R34 0.378 0.164-0.544 < 0.01 0.417 0.211-0.641 < 0.01 R35 R36 R37 R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 75 R1 Reliability R2 The Carolinas Comfort Scale showed an excellent internal consistency, with a Cronbach’s α R3 coefficient of 0.948 (>0.7). The Cronbach’s coefficients ranged from 0.944-0.951 when a variable R4 was deleted. R5 R6 Test- retest reliability R7 Ninety-two patients (92 %) completed the second Carolinas Comfort Scale three weeks after R8 R9 surgery. Spearman’s correlation coefficient showed a correlation of 0.53 (ci 0.387-0.669, p < R10 0.01) for the total score of the Carolinas Comfort Scale in the test- retest validation (figure 1). R11 The correlation coefficients for the separate questions between the two different administrations R12 ranged from 0.247-0.563. This correlation was significant in all questions (table 4). R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 Figure 1: test-retest reliability. Total scores of the initial survey (CCS1) compared to the total score of the R35 second survey (CCS2). This figure shows a trend towards recovery three weeks after surgery; most dots are R36 located below the line of optimal agreement. R37 R38 R39

76 | Chapter 6 Construct validity R1 The validity of the Carolinas Comfort Scale was determined by comparing the scores of the R2 Carolinas Comfort Scale and the different domain scores of the SF-36. Spearman’s rank showed R3 R4 a correlation between the different domains of the SF-36 and the Carolinas Comfort Scale R5 ranging from -0.006 to -0.479 (table 4). The best correlations were found in the domains physical R6 functioning and bodily pain (-0.479 and -0.437 respectively). In the domains role physical, vitality R7 and social functioning the correlation with the Carolinas Comfort Scale was also significant. Only R8 the domains general health, role emotional and mental health showed no significant correlations. R9 R10 Table 4: Correlations between CCS and different domains of SF 36 R11 Category Correlation 95% confidence interval p Value R12 Physical Functioning -0.479 -0.658- -0.305 0.000* R13 Role-Physical functioning -0.259 -0.450- -0.019 0.01* Bodily Pain -0.437 -0.596- -0.222 0.00* R14 General Health -0.054 -0.283- 0.124 0.592 R15 Vitality -0.201 -0.406- 0.002 0.046* R16 Social Functioning -0.275 -0.468- -0.041 0.006* R17 Role Emotional -0.066 -0.255- 0.168 0.519 Mental Health -0.102 -0.319- 0.104 0.316 R18 R19 * significant correlation R20 R21 Principal component analysis 6 R22 The principal component analysis determined three components, with the first component R23 explaining 52% of the variance (question 1a; sensation of the mesh while lying down). After R24 deleting this item the Crohnbach’s alpha was 0.951. All factor loadings for this first component R25 were > 0.3 for the unrotated solution. R26 R27 R28 Discussion R29 R30 To validate the Carolina’s Comfort Scale in Dutch we compared our results to the results of R31 Heniford et al (6). The Carolinas Comfort Scale appears to be a valid and specific instrument R32 to measure quality of life after hernia surgery. The unique and additive value of the Carolinas R33 R34 Comfort Scale is its focus on pain, presence of mesh sensation and limitations of movements R35 during walking, laying down, bending over and straining. In contrast, the SF-36 is a generic tool R36 to determine quality of life assessing more general variables such as bodily pain, mental health, R37 social and role functioning. Bodily pain does not specifically reflect pain related to surgical repair R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 77 R1 of a hernia. The impact of hernia surgery on mental health, role functioning and social functioning R2 seems limited rendering the SF-36 less suitable to assess outcome in patients after hernia surgery R3 (24-26). This is confirmed by the lack of correlation between the Carolinas Comfort Scale scores R4 and the domains general health, role-emotional and mental health which is fairly similar to the R5 findings of Heniford et al (6). R6 The use of simple and unequivocal questions is essential in questionnaires to generate consistent R7 and reliable findings that are reproducible. This is quantified by ‘test-retest reliability’. Ideally, R8 R9 tests and retests are studied in patients with unchanged health conditions. In this study we R10 found a moderate ‘test-retest reliability’ of 0.53, whereas a reliability of 0.7 is desired (29). We R11 noted lower scores, reflecting less discomfort or fewer restrictions, during the retest, which was R12 done three weeks after the first test (figure 1). This is in accordance with expectations regarding R13 recovery time after hernia surgery. In our study, the period of three weeks between the test and R14 the retest appears too long because the condition of the patient at three weeks after surgery R15 was improved compared with the condition at the time of the first test. However, we believe R16 that if the period between the questionnaires is shorter, patients can remember their previous R17 answers. Heniford et al. used an interval between the two questionnaires of 6 months. It should R18 be stressed that our test-retest reliability is within the range reported by Heniford et al (6) and this R19 outcome is important in the comparison of the English and Dutch survey. R20 Questions left unanswered in questionnaires are another indicator of quality. In this study, R21 four percent of the returned SF-36 questionnaires had one or more missing answers while all R22 Carolinas Comfort Scale questionnaires were complete except for physical exercise. This question R23 R24 was deemed inappropriate considering that patients had been instructed not to initiate physical R25 exercise during the first six weeks after surgery. R26 All items of a questionnaire, which is designed to measure in the same general construct, should R27 produce similar scores. This is called the internal consistency of a test. The Carolinas Comfort R28 Scale shows an excellent internal consistency, comparable to the original paper (6). Deleting R29 question 1a of the Carolinas Comfort Scale can even increase this high outcome. However, we R30 are very satisfied with an internal consistency of 0.944 and we prefer to use a questionnaire R31 comparable to the English version over a slightly improved internal consistency. Over three R32 quarters of all patients preferred the Carolinas Comfort Scale in comparison to the SF-36 (table R33 2). This is another indication of its feasibility. R34 A possible limitation of this study was a preponderance of patients with inguinal hernias. However, R35 the Carolinas Comfort Scale was designed for surgical abdominal wall hernia repair with mesh in R36 general and evidence exists of successful employment of the questionnaire in patients with both R37 inguinal as with incisional hernias (27;28). R38 R39

78 | Chapter 6 In conclusion, the Carolinas Comfort Scale seems a short, feasible and effective questionnaire R1 to measure quality of life after surgical repair of abdominal wall hernias with mesh in a Dutch R2 population, compared to the English version. Adoption of this disease specific questionnaire by R3 R4 more countries will facilitate international studies and evaluation of quality of life outcomes of R5 hernia surgery. R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 6 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 79 R1 References R2 R3 1. Primatesta P, Goldacre MJ (1996) Inguinal hernia repair: incidence of elective and emergency surgery, readmission and mortality. Int J Epidemiol 25:835-839 R4 2. Kingsnorth A, LeBlanc K (2003) Hernias: inguinal and incisional. Lancet 362:1561-1571 R5 3. Muschaweck U (2003) Umbilical and epigastric hernia repair. Surg Clin North Am 83:1207-1221 R6 4. den Hartog D, Dur AHM, Tuinebreijer WE, Kreis RW (2008) Open surgical procedures for incisional R7 hernias. Cochrane Database Syst RevCD006438 R8 5. Nieuwenhuizen J, Kleinrensink GJ, Hop WCJ, Jeekel J, Lange JF (2008) Indications for incisional hernia R9 repair: an international questionnaire among hernia surgeons. Hernia 12:223-225 6. Heniford BT, Walters AL, Lincourt AE, Novitsky YW, Hope WW, Kercher KW (2008) Comparison of R10 generic versus specific quality-of-life scales for mesh hernia repairs. J Am Coll Surg 206:638-644 R11 7. Urbach DR (2005) Measuring quality of life after surgery. Surg Innov 12:161-165 R12 8. Wright JG (1999) Outcomes research: what to measure. World J Surg 23:1224-1226 R13 9. Fitzgibbons RJJ, Giobbie-Hurder A, Gibbs JO, Dunlop DD, Reda DJ, McCarthy MJ, Neumayer LA, Barkun R14 JST, Hoehn JL, Murphy JT, Sarosi GAJ, Syme WC, Thompson JS, Wang J, Jonasson O (2006) Watchful waiting vs repair of inguinal hernia in minimally symptomatic men: a randomized clinical trial. JAMA R15 295:285-292 R16 10. Thompson JS, Gibbs JO, Reda DJ, McCarthy MJ, Wei Y, Giobbie-Hurder A, Fitzgibbons RJJ (2008) Does R17 delaying repair of an asymptomatic hernia have a penalty? Am J Surg 195:89-93 R18 11. van den Heuvel B, Dwars BJ, Klassen DR, Bonjer HJ (2011) Is surgical repair of an asymptomatic groin hernia appropriate? A review. Hernia 15:251-259 R19 12. Burger JWA, Luijendijk RW, Hop WCJ, Halm JA, Verdaasdonk EGG, Jeekel J (2004) Long-term follow-up R20 of a randomized controlled trial of suture versus mesh repair of incisional hernia. Ann Surg 240:578- R21 583 R22 13. Heniford BT, Park A, Ramshaw BJ, Voeller G (2003) Laparoscopic repair of ventral hernias: nine years’ experience with 850 consecutive hernias. Ann Surg 238:391-399 R23 14. EU Hernia Trialists Collaboration. (2000) Mesh compared with non-mesh methods of open groin hernia R24 repair: systematic review of randomized controlled trials. Br J Surg 87:854-859 R25 15. Eklund A, Rudberg C, Leijonmarck CE, Rasmussen I, Spangen L, Wickbom G, Wingren U, Montgomery R26 A (2007) Recurrent inguinal hernia: randomized multicenter trial comparing laparoscopic and Lichtenstein repair. Surg Endosc 21:634-640 R27 16. Fleming WR, Elliott TB, Jones RM, Hardy KJ (2001) Randomized clinical trial comparing totally R28 extraperitoneal inguinal hernia repair with the Shouldice technique. Br J Surg 88:1183-1188 R29 17. Langeveld HR, van’t Riet M, Weidema WF, Stassen LPS, Steyerberg EW, Lange J, Bonjer HJ, Jeekel R30 J (2010) Total extraperitoneal inguinal hernia repair compared with Lichtenstein (the LEVEL-Trial): a randomized controlled trial. Ann Surg 251:819-824 R31 18. Schmedt CG, Sauerland S, Bittner R (2005) Comparison of endoscopic procedures vs Lichtenstein and R32 other open mesh techniques for inguinal hernia repair: a meta-analysis of randomized controlled trials. R33 Surg Endosc 19:188-199 19. Bittner R, Arregui ME, Bisgaard T, Dudai M, Ferzli GS, Fitzgibbons RJ, Fortelny RH, Klinge U, Kockerling R34 F, Kuhry E, Kukleta J, Lomanto D, Misra MC, Montgomery A, Morales-Conde S, Reinpold W, Rosenberg R35 J, Sauerland S, Schug-Pass C, Singh K, Timoney M, Weyhe D, Chowbey P (2011) Guidelines for R36 laparoscopic (TAPP) and endoscopic (TEP) treatment of inguinal hernia [International Endohernia Society (IEHS)]. Surg Endosc 25:2773-2843 R37 20. Burger JWA, Lange JF, Halm JA, Kleinrensink GJ, Jeekel H (2005) Incisional hernia: early complication R38 of abdominal surgery. World J Surg 29:1608-1613 R39

80 | Chapter 6 21. Simons MP, Aufenacker T, Bay-Nielsen M, Bouillot JL, Campanelli G, Conze J, de Lange D, Fortelny R, Heikkinen T, Kingsnorth A, Kukleta J, Morales-Conde S, Nordin P, Schumpelick V, Smedberg S, R1 Smietanski M, Weber G, Miserez M (2009) European Hernia Society guidelines on the treatment of R2 inguinal hernia in adult patients. Hernia 13:343-403 R3 22. Aslani N, Brown CJ (2010) Does mesh offer an advantage over tissue in the open repair of umbilical hernias? A systematic review and meta-analysis. Hernia 14:455-462 R4 23. Sajid MS, Bokhari SA, Mallick AS, Cheek E, Baig MK (2009) Laparoscopic versus open repair of R5 incisional/ventral hernia: a meta-analysis. Am J Surg 197:64-72 R6 24. Brazier JE, Harper R, Jones NM, O’Cathain A, Thomas KJ, Usherwood T, Westlake L (1992) Validating R7 the SF-36 health survey questionnaire: new outcome measure for primary care. BMJ 305:160-164 R8 25. Patrick DL, Deyo RA (1989) Generic and disease-specific measures in assessing health status and quality of life. Med Care 27:S217-S232 R9 26. Burney RE, Jones KR, Coon JW, Blewitt DK, Herm A, Peterson M (1997) Core outcomes measures for R10 inguinal hernia repair. J Am Coll Surg 185:509-515 R11 27. Belyansky I, Tsirline VB, Klima DA, Walters AL, Lincourt AE, Heniford TB (2011) Prospective, comparative R12 study of postoperative quality of life in TEP, TAPP, and modified Lichtenstein repairs. Ann Surg 254:709- 714 R13 28. Hope WW, Lincourt AE, Newcomb WL, Schmelzer TM, Kercher KW, Heniford BT (2008) Comparing R14 quality-of-life outcomes in symptomatic patients undergoing laparoscopic or open ventral hernia R15 repair. J Laparoendosc Adv Surg Tech A 18:567-571 R16 29. BB Gerstman (2008) Basic Biostatistics: Statistics for Public Health Practice. Jones and Bartlett Publishers. Sudbury, Canada, R17 R18 R19 R20 R21 6 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 81 R1 Appendix R2

R3 CarolinasComfortScale™ R4 Dit is een vragenlijst over uw kwaliteit van leven. R5 Beantwoord alstublieft ALLE vragen voor elk van de 8 activiteiten. Gebruik nvt (niet van toepassing) R6 als u een activiteit niet verricht. Omcirkel het juiste antwoord. (0= niet, 5= heel erg) R7 R8 R9 1. Als u gaat liggen, voelt u dan R10 R11 a.) de mat zitten 0 1 2 3 4 5 nvt R12 b.) Pijn 0 1 2 3 4 5 nvt R13 R14 R15 2. Wanneer u bukt, voelt u dan: R16 R17 a.) de mat zitten 0 1 2 3 4 5 nvt R18 b.) Pijn 0 1 2 3 4 5 nvt R19 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R20 R21 R22 3. Wanneer u gaat zitten, voelt u dan: R23 R24 R25 a.) de mat zitten 0 1 2 3 4 5 nvt R26 b.) pijn 0 1 2 3 4 5 nvt R27 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R28 R29 R30 4. In uw dagelijks leven (bijvoorbeeld bij het uit bed stappen, douchen, aankleden) voelt u dan: R31 R32 a.) de mat zitten 0 1 2 3 4 5 nvt R33 b.) pijn 0 1 2 3 4 5 nvt R34 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R35 R36 R37 R38 R39

82 | Chapter 6 5. Wanneer u hoest of diep adem haalt, voelt u dan: R1 R2 a.) de mat zitten 0 1 2 3 4 5 nvt R3 R4 b.) pijn 0 1 2 3 4 5 nvt R5 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R6 R7 R8 6. Wanneer u loopt of staat, voelt u dan: R9 R10 a.) de mat zitten 0 1 2 3 4 5 nvt R11 b.) pijn 0 1 2 3 4 5 nvt R12 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R13 R14 R15 7. Wanneer u de trap op of af loopt, voelt u dan: R16 R17 a.) de mat zitten 0 1 2 3 4 5 nvt R18 R19 b.) pijn 0 1 2 3 4 5 nvt R20 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R21 6 R22 R23 8. Wanneer u sport (anders dan werkgerelateerd), voelt u dan: R24 R25 a.) de mat zitten 0 1 2 3 4 5 nvt R26 b.) pijn 0 1 2 3 4 5 nvt R27 c.) een bewegingsbeperking 0 1 2 3 4 5 nvt R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

Comparison of the Dutch and English version of the Carolinas Comfort Scale; a specific quality of life-questionnaire | 83

Chapter 7

Laparoscopic incisional hernia repair:

Influence of surgical technique on recurrence rate

A systematic review of the literature

M.M. Poelman J.D. Deelder E. de Lange W.H. Schreurs H.J. Bonjer

Submitted R1 Abstract R2

R3 Introduction Recent studies reported that laparoscopic incisional hernia repair is at least as R4 effective as the open approach. The technique of laparoscopic incisional hernia repair has not R5 been standardized. R6 R7 Methods A systematic review of the literature was performed to evaluate the surgical technique R8 R9 of laparoscopic incisional hernia repair with outcomes. PubMed was searched using the R10 following key words; incisional hernia, ventral hernia, mesh, fixation, laparoscopy, R11 and combinations of these words. Relevant articles published prior to August 2012 were selected. R12 Methodological Index of Nonrandomized Studies (MINORS) criteria were adapted for this topic. R13 Two independent researchers appraised all the publications with the use of these modified R14 MINORS criteria to assess their methodology. Primary outcome was recurrence rate. R15 A meta-analysis was performed for the influence of three factors (number of transfascial sutures, R16 type of mesh and overlap of the mesh) on recurrence rates. Forest plots were used as a graphical R17 design to display the relative strength of each individual study. R18 R19 Results Twenty-one articles, with a total number of 2353 patients were selected for evaluation. R20 Indications for repair were unclear in almost all studies. Mesh was employed in all studies. The R21 conversion rate to an open procedure was 2.8%. Relaparotomies were performed in 2.7% of all R22 patients in less than a week after index surgery. Recurrences were determined based on physical R23 R24 examinations, the reported recurrence rate was 5,2%. R25 Analysis of the subgroups (overlap of < 3cm vs overlap of >5cm/use of ≥4 TFS vs use of ≤2 TFS/ R26 Dual mesh vs Parietex mesh) did not show any significant difference in recurrence rates. R27 R28 Discussion In spite of numerous reports on laparoscopic incisional hernia repair, a preferred R29 surgical technique has not yet been determined. R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

86 | Chapter 7 Introduction R1 R2

Incisional hernias are defects of the fascia of the abdominal wall, covered by skin, which develop R3 R4 after open abdominal surgery. Bulging of abdominal contents through the scar occurs when R5 patients are standing up or coughing. Incisional hernias may be asymptomatic, but are frequently R6 associated with pain or discomfort affecting quality of life and economic productivity. Entrapment R7 of bowel jeopardizing the blood supply, strangulation, is the most concerning consequence of R8 incisional hernias. Incisional hernias do affect the quality of life and economic productivity of R9 patients (1,2). Obesity, wound infections and collagen disorders are risk factors for developing R10 incisional hernias (3,4). R11 Currently, eighty percent of all patients with an incisional hernia undergo surgical repair (5) in R12 the Western world. Clear criteria to determine whether either surgical repair or conservative R13 approach is preferable have not yet been determined. A wide variety of surgical techniques, both R14 open and laparoscopic, to repair incisional hernias exist. R15 Infection of surgical incisions, skin necrosis, seroma and infection of the prosthetic material R16 are potential complications of incisional hernia surgery. Extensive mobilization of the skin and R17 subcutaneous tissue endangering the blood supply and exposure of prosthetic material to large R18 R19 incisions predispose to impaired wound healing and subsequent infection. Laparoscopic surgery R20 could improve outcomes of incisional hernia repair because it employs small incisions and it R21 avoids a blunt traumatic dissection. Less pain, shorter hospital stay and fewer complications after R22 laparoscopic incisional hernia repair have been reported. Two recent meta-analyses (6,7) that R23 included 366 and 526 patients (overlapping studies were included in these two analyses) reported R24 that laparoscopic repair was at least as effective and possibly superior to the open approach in R25 terms of hospital stay and post-operative complications. The technique of laparoscopic incisional 7 R26 hernia repair has not been standardized. R27 R28 A review of the literature was performed to evaluate the surgical technique of laparoscopic R29 incisional hernia repair with outcomes, to define the optimal technique. R30 R31 R32 Methods R33 R34 R35 Search strategy R36 For this review PubMed was searched and relevant articles were identified published prior to R37 August 2012, using the following key words; incisional hernia, ventral hernia, mesh, fixation, R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 87 Methods Search strategy For this review PubMed was searched and relevant articles were identified published prior to August 2012, using the following key words; incisional hernia, ventral hernia, mesh, fixation, laparoscopy, endoscopy and combinations of these words. A flowchart of the R1 search strategylaparoscopy, is shown inendoscopy figure 1. Furthermore,and combinations reference of these lists words. of these A flowchart articles were of the cross- search strategy is R2 shown in figure 1. Furthermore, reference lists of these articles were cross-searched for additional searched for additional literature. There was no data limit set, and only papers written in English R3 literature. There was no data limit set, and only papers written in English were included. Papers R4 incisional were included.that Papers did not that describe did not laparoscopic describe laparoscopic incisional hernia repair, hernia but also repair, ventral but herniaalso repair and that R5 ventral herniadid repair not differentiate and that did between not differentiate these two betweengroups were these excluded. two groups In case were of overlapping excluded. In studies, the R6 case of overlappingstudy with studies, the longest the study study-period with the longest was chosen. study-period was chosen. R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 Figure 1: flowchart of the search strategy R22 R23 Figure 1: flowchart of the search strategy R24 MINORS criteria R25 Methodological Index of Nonrandomized Studies, also known as the ‘MINORS’ criteria, (8) was R26 MINORS criteriadeveloped Methodological as a tool to Index assess of theNonrandomized methodology Studies,of observational also known studies as the such ‘MINORS’ as case-control and R27 cohort designs. Although an increasing number of randomized controlled trials are conducted, criteria, [8] was developed as a tool to assess the methodology of observational studies such as R28 most available evidence in surgery comes from non-randomized studies. However, a systematic case-control and cohort designs. Although an increasing number of randomized controlled trials R29 review or meta-analysis of the combined results of observational studies of varying quality R30 are conducted,could most be availablehighly biased. evidence The MINORSin surgery criteria comes were from developed non-randomized to perform studies. a quality assessment of R31 However, a systematicobservational review studies or meta-analysisbefore conducting of the a combinedsystematic resultsreview ofwith observational these studies. studies It is a validated R32 of varying qualitytool (8).could The be MINORS highly biased. criteria The can MINORS be adapted criteria to werespecific developed topics ofto the perform research. a In this study R33 the modification entailed specification to studies that describe the technique of laparoscopic R34 quality assessment of observational studies before conducting a systematic review with these incisional hernia repair (modified MINORS, table 1). These modified MINORS criteria were used to R35 studies. It is a validated tool [8]. The MINORS criteria can be adapted to specific topics of the assess the quality of the observational studies. R36 research. In this study the modification entailed specification to studies that describe the R37 R38 R39 76 88 | Chapter 7 Table 1: Modified MINORS R1 0 1 2 R2 1. Clearly stated aim No aim described Partially described (i.e. Clearly stated aim R3 evaluation of a case serie) R4 2. Number of included <20 >20 patients R5 3. Inclusion of consecutive Was not described Only a time frame (i.e. from Consecutive patients + R6 patients 1997 until 2000) patient characteristics. R7 4. Type of hernia specified Unspecified Only ‘incisional hernia’ Specification of the location R8 specified and size of the hernia R9 5. Surgical technique Was not reported Reported incomplete (i.e. Completely specified, type of mesh was not including type of mesh, type R10 specified) of fixation and cm overlap. R11 6. Report of end points Was not reported Only some endpoints All complications reported. R12 reported (i.e. recurrences) R13 R14 Critical appraisal R15 Two independent researchers (MMP and JDD) appraised all the publications and scored them R16 using the modified MINORS. In case of disagreement, a senior researcher (WHS) was asked for R17 help and made the final decision whether to in- or exclude the study. Publications with a score of R18 R19 less than 9 were excluded, as well as publications that scored ‘zero’ on any item of the modified R20 MINORS. Studies that did not describe the full surgical technique including type of mesh, overlap R21 of the mesh of the fascia and type of fixation (i.e. minimum of 2 point on MINORS point 5) were R22 also excluded. Overlapping cohorts were identified and the study with the longest study period R23 was included. Only studies with a median follow-up of at least 12 months were included in the R24 analysis. R25 7 R26 Primary and Secondary Outcome R27 The primary outcome was recurrence of the incisional hernia. Secondary outcomes were wound- R28 and mesh infection and pain. R29 R30 Data Extraction R31 All reports were thoroughly reviewed, and data for primary and secondary outcomes were R32 extracted. Study design, year of publication, number of included and evaluated patients, surgical R33 R34 technique (choice of mesh, choice and number of transfascial sutures, choice of tackers and R35 centimeters of overlap), morbidity, re-interventions and duration of follow-up were listed. R36 Three subgroups were formed for differences in surgical technique: choice of mesh, number of R37 transfascial sutures used and amount of overlap of the mesh over the fascia. R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 89 R1 Analysis A meta-analysis (applying the random effects method of DerSimonian-Laird) was R2 performed for each of these subgroups to see if any combination of variables would show a R3 certain trend in influence on recurrence rate. Forest plots were used as a graphical design to R4 display the relative strength of each individual study. A line represents each study; the width of R5 the line shows the 95%- confidence interval of the effect estimate of the individual studies. The R6 area of the box represents the weight given to a study. The diamond below the studies represents R7 the overall effect; the width of the diamond shows the confidence intervals of the overall effect R8 R9 estimate. R10 R11 R12 Results R13 R14 Twenty-one articles, with a total number of 2353 patients were selected for evaluation (9-29) R15 (Table 2). Three randomized controlled trials on laparoscopic surgical technique were found (30- R16 32) but excluded for analysis. Reasons for exclusion were inclusion of both primary ventral and R17 incisional hernias and lack of follow up. R18 R19 Indications for repair were unclear in all studies, except for one study (23) on incarcerated incisional R20 hernias. Mesh was employed in all studies and all but one study reported to use tacker fixation R21 of the mesh, with or without transfascial sutures. The conversion rate to an open procedure was R22 2.8%. Re-interventions were performed because of suspected bowel injury, trocar site hernia, R23 R24 intra-abdominal bleeding, mesh infection and extreme pain. Relaparotomies were performed in R25 2.7% of all patients in less than a week after index surgery. Removal of mesh at relaparotomy for R26 bowel perforation was not reported as a recurrence. R27 R28 Follow-up studies were done mostly in clinic and included physical examination. Hence recurrences R29 were determined based on physical examinations. Only 2 studies reported use of CT scan or R30 ultrasonography to confirm recurrences, while in other studies the presence of a recurrent hernia R31 at reoperation was considered evidence of a recurrence. Overall, there was a reported recurrence R32 rate of 5.2% in this analysis. R33 R34 Only 10 authors reported on post-operative chronic pain. Validated pain-scores were seldom R35 used. Three mortalities were reported due to cardio-pulmonary events. Trocar site hernias were R36 only recorded in 6 out of 1115 patients (0.5 %). R37 R38 R39

90 | Chapter 7 Table 2 R1 study n= M type of mesh TFS overlap FU C R SSI MI re-lap BI M TSH P R2 Bageacu / 2002 (9) 159 12 various variable 5cm 49 21 19 3 0 3 10 0 U 31 Bencini/ 2003 (10) 42 11 Dual Mesh 4 3-4cm 17 0 0 0 0 0 2 0 U U R3 Berger/ 2002 (11) 150 10 Dual Mesh >4 3-5 cm 12 1 4 0 1 4 4 1 4 U R4 Berger/ 2009 (12) 297 10 Dynamesh >4 5cm 24 1 2 2 1 5 1 1 1 6 R5 Carbajo/ 2003 (13) 270 9 Dual Mesh 0 5cm 44 1 12 0 U 2 9 0 U 20 R6 Cecceralli/ 2008 (14) 94 10 Composix 4 3-5cm 38 0 2 0 0 0 0 U U 0 Heniford/ 2000 (15) 100 9 ePTFE >4 3-4cm 22.5 0 1 0 1 2 1 U U U R7 Kirshtein/ 2002 (16) 103 10 Dual Mesh 4 3cm 26 3 4 3 2 0 2 0 0 U R8 Koehler/ 1999 (17) 32 11 Dual Mesh >6 5cm 20 U 3 2 1 2 2 1 U U R9 Kurmann / 2011 (18) 69 12 Dual-layered >4 5cm 33 7 11 4 U 17 U 0 U 13 R10 Liang / 2012 (19) 22 11 Coated polyester >4 6cm 21 U 0 0 0 5 U 0 0 U Moreno Egea/ 2010 (20) 200 11 Parietex 4 5cm 60 5 11 1 0 0 5 0 0 0 R11 Motson/ 2006 (21) 117 10 Prolene 0 3cm 42 5 9 0 3 4 6 U U U R12 Olmi / 2006 (22) 156 10 Parietex 0 4-5cm 29 0 4 U 1 U 7 0 0 3 R13 Olmi / 2009 (23) 48 9 Parietex 0 4-5cm 38 0 0 U 0 0 2 0 0 U R14 Riet van ‘t/ 2002 (24) 25 10 Polypropylene variable 3cm 17 3 4 1 0 0 2 U U U Stickel / 2007 (25) 62 9 Dual Mesh 4 5cm 13 1 3 1 1 1 1 0 U 19 R15 Sturt/ 2011 (26) 227 11 Various <2 3cm 17 8 25 5 3 7 0 U U 8 R16 Verbo et al/ 2007 (27) 41 9 Dual Mesh 0 3-4cm 38 0 1 0 0 1 1 0 0 U R17 Wolter / 2009 (28) 41 9 Various 4 3cm 23 2 3 1 1 2 1 0 U 4 R18 Yannam/ 2011 (29) 98 11 Various >4 3cm 32 9 9 1 4 8 2 0 1 U 2353 127 R19 R20 U= unknown/ M= minors score/ TFS= Transfascial sutures/ FU= median follow-up in months/ C= conversion R21 to open procedure R= recurrence/ SSI= surgical site infection/ MI= mesh infection R22 BI= bowel injury/ M= mortality/ TSH= trocar site hernia/ P= pain R23 R24 Correlation of the surgical technique and recurrence rate R25 Overlap of mesh 7 R26 The degree of overlap of the mesh relative to the fascial margin was reported in all but one R27 article. An analysis was done to determine recurrence rates associated with overlap of less than 3 R28 centimeters and overlap greater than 5 centimeters (table 3 and figure 2). The forest plot (figure R29 2) shows the number of recurrences (from zero to a hundred percent) for each study and their R30 95%-confidence interval. The weight of the study is represented by the size of the box. When R31 more than 5cm overlap was used, the overall recurrence rate was 6%. When 3cm or less overlap R32 was used, the overall recurrence rate was 9.1%. This was not a significant difference. R33 R34 R35 R36 R37 R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 91 Table 3: Included studies for overlap of the mesh over the fascia. R1 study n= overlap median FU R R2 Kirshtein/ 2002 103 ≤3cm 26 months 4 R3 Motson/ 2006 117 ≤3cm 42 monhts 9 R4 Riet van ‘t/ 2002 25 ≤3cm 17 months 4 R5 Sturt/ 2011 227 ≤3cm 17 months 25 Wolter/ 2009 41 ≤3cm 23 months 3 R6 Yannam/ 2011 98 ≤3cm 32 months 9 R7 total 611 R8 Bageacu/ 2002 159 ≥5cm 49 months 19 R9 Berger/ 2009 297 ≥5cm 24 months 2 Carbajo/ 2003 270 ≥5cm 44 months 12 R10 Koehler/ 1999 32 ≥5cm 20 months 3 R11 Kurmann/ 2011 69 ≥5cm 33 months 11 R12 Liang / 2012 22 ≥5cm 21 months 0 R13 Moreno Egea/ 2010 200 ≥5cm 60 months 11 R14 Stickel/ 2007 62 ≥5cm 13 months 3 total 1111 R15 R=recurrence R16 FU= follow up/ R= number of recurrences. R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 Figure 2: Forest plot for overlap of the mesh over the fascia R37 Figure 2: Forest plot for overlap of the mesh over the fascia R38 R39 Number of transfascial sutures. The number of transfascial sutures (TFS) used in each group was listed. Two studies were excluded from the analysis because they reported to use TFS in ‘6 out 92of 25’| Chapter patients 7 and one group reported to use either 1 or 4 TFS. Twenty-two studies were used in the analysis (table 4 and figure 3). In the subgroup of studies, where ≥4 TFS were used, the overall recurrence rate was 4.5%. In the subgroup where ≤2 TFS were used the overall recurrence rate was 5.3%. No clear trend could be noticed. As pain was not reported in most of the studies, it was not possible to investigate the relationship between the number of TFS and pain.

81 Number of transfascial sutures R1 The number of transfascial sutures (TFS) used in each group was listed. Two studies were excluded R2 from the analysis because they reported to use TFS in ‘6 out of 25’ patients and one group R3 R4 reported to use either 1 or 4 TFS. Twenty-two studies were used in the analysis (table 4 and figure R5 3). In the subgroup of studies, where ≥4 TFS were used, the overall recurrence rate was 4.5%. In R6 the subgroup where ≤2 TFS were used the overall recurrence rate was 5.3%. No clear trend could R7 be noticed. As pain was not reported in most of the studies, it was not possible to investigate the R8 relationship between the number of TFS and pain. R9 R10 Table 4: included studies in analysis for transfascial sutures (TFS). R11 study n= TFS median FU R Bencini/ 2003 42 ≥4 17 months 0 R12 Berger/ 2002 150 ≥4 12 months 4 R13 Berger/ 2009 297 ≥4 24 months 2 R14 Cecceralli/ 2008 94 ≥4 38 months 2 R15 Heniford/ 2000 100 ≥4 22.5 months 1 Kirshtein/ 2002 103 ≥4 26 months 4 R16 Koehler/ 1999 32 ≥4 20 months 3 R17 Kurmann/ 2011 69 ≥4 33 months 11 R18 Liang/ 2012 22 ≥4 21 months 0 R19 Moreno Egea/ 2010 200 ≥4 60 months 11 Stickel/ 2007 62 ≥4 13 months 3 R20 Wolter/ 2009 41 ≥4 23 months 3 R21 Yannam/ 2011 98 ≥4 32 months 9 R22 total: 1310 R23 Carbajo/ 2003 270 ≤2 44 months 12 R24 Motson/ 2006 117 ≤2 42 monhts 9 Olmi/ 2006 156 ≤2 29 months 4 R25 Olmi/ 2009 48 ≤2 38 months 0 7 R26 Sturt/ 2011 227 ≤2 17 months 25 R27 Verbo/ 2007 41 ≤2 38 months 1 R28 total: 859 R= recurrence R29 R30 FU= follow up/ R= number of recurrences R31 R32 R33 R34 R35 R36 R37 R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 93

Table 4: included studies in analysis for transfascial sutures (TFS). FU= follow up/ R= number of recurrences

R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 FigureFigure 3: 3: Forest Forest plot plotfor number for number of transfacial of transfacial sutures (TFS) sutures used (TFS) used R22 Type of mesh R23 R24 In this review, Parietex composite mesh (Covidien, n=404) and Dual Mesh (Gore, n=700) were most frequently used. The studies using one of these meshes were extracted and compared for R25 82 R26 a difference in recurrence (table 5 and figure 4). In the Parietex group, the overall recurrence rate R27 was 3.8% while in the Dual mesh subgroup the overall recurrence rate was 4.2%. R28 In the Dual Mesh group 5 mesh infections were reported in these studies whereas 1 mesh R29 infection was reported in the Parietex group. This was not a significant difference. R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

94 | Chapter 7 Table 5: included studies in analysis for Parietex vs DualMesh R1 study n= mesh median FU R Moreno Egea/ 2010 200 1 60 months 11 R2 Olmi/ 2006 156 1 29 months 4 R3 Olmi/ 2009 48 1 38 months 0 R4 total: 404 R5 Bencini/ 2003 42 2 17 months 0 Berger/ 2002 150 2 12 months 4 R6 Carbajo/ 2003 270 2 44 months 12 R7 Kirshtein/ 2002 103 2 26 months 4 R8 Koehler/ 1999 32 2 20 months 3 R9 Stickel/ 2007 62 2 13 months 3 R10 Verbo/ 2007 41 2 38 months 1 total: 700 R11 Parietex=1/ Dual mesh= 2 R12 R=recurrence R13 Type of mesh 1= Parietex/ 2= Dual Mesh. R14 FU= follow up/ R= number of recurrences R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 7 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 Figure 4: Forest plot for Dual mesh vs Parietex mesh Figure 4: Forest plot for Dual mesh vs Parietex mesh R37 R38 Incisional hernias of the abdominal wall occur in 15 to 20 percent after laparotomy [1]. R39 However, only some of these patients who develop incisional hernias undergo surgery because Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 95 many of these hernias are asymptomatic. Evidence regarding the necessity to undertake a repair of an incisional hernia is not available. It is surprising that the considerations for incisional hernia repair were not recorded in the studies that were reviewed. Accurate documentation of the severity and localization of pain, range of physical activity and cosmesis before and after surgery is required to assess the benefit of incisional hernia surgery. Furthermore, more information on the natural course of incisional hernias is needed to validate a ‘wait and see’ policy in patients with incisional hernias.

There are a wide variety of meshes and fixation techniques available to the surgical team to reconstruct the abdominal wall. The requirements for these meshes include compliance similar to that of the abdominal wall of the patient, good attachment to the abdominal wall opposed to

84 R1 Discussion R2

R3 Laparoscopic surgery is progressively employed in patients with incisional hernia because this R4 minimally invasive technique is considered to be associated wit short-term advantages such as R5 reduced pain, earlier recovery and shorter hospital stay (6,7). In spite of numerous reports on R6 laparoscopic incisional hernia repair, a preferred surgical technique has not yet been determined. R7 Long term restoration of the integrity of the abdominal wall without postoperative pain or risk of R8 R9 visceral adhesions is the ultimate goal of incisional hernia repair. R10 R11 Incisional hernias of the abdominal wall occur in 15 to 20 percent after laparotomy (1). However, R12 only some of these patients who develop incisional hernias undergo surgery because many of R13 these hernias are asymptomatic. Evidence regarding the necessity to undertake a repair of an R14 incisional hernia is not available. It is surprising that the considerations for incisional hernia repair R15 were not recorded in the studies that were reviewed. Accurate documentation of the severity and R16 localization of pain, range of physical activity and cosmesis before and after surgery is required R17 to assess the benefit of incisional hernia surgery. Furthermore, more information on the natural R18 course of incisional hernias is needed to validate a ‘wait and see’ policy in patients with incisional R19 hernias. R20 R21 There are a wide variety of meshes and fixation techniques available to the surgical team to R22 reconstruct the abdominal wall. The requirements for these meshes include compliance similar R23 R24 to that of the abdominal wall of the patient, good attachment to the abdominal wall opposed R25 to lack of adherence to the viscera, pliability allowing insertion of a large mesh through a trocar R26 and resistance to micro-organisms. Evidence providing guidance to surgeons and patients for R27 selecting the optimal mesh is not available. Employment of various meshes combined with R28 different fixation techniques renders such an analysis very difficult. Hence, this review of more R29 than 2,000 patients has not provided a better understanding of the outcomes of different meshes R30 and fixation techniques. R31 R32 An overlap of mesh of at least 3-5 centimeters is recommended in all studies included in the R33 analysis. The rationale is mesh shrinkage, which appears to be influenced by the pore-size, weight R34 of the mesh, fixation method of the mesh and the inflammatory response of the host. This review R35 showed a trend towards a lower recurrence rate when the overlap of the mesh was greater than R36 5 centimeters. R37 R38 R39

96 | Chapter 7 Transfascial sutures are used to keep the mesh in place and position the mesh over the defect. R1 Transfascial sutures might cause post-operative pain due to entrapment of nerves of the R2 abdominal wall in the knot of the suture. Besides transfascial sutures, the mesh is often fixated to R3 R4 the abdominal wall with the use of tacks or sutures. R5 The randomized controlled studies on the influence of surgical technique (i.e. tacker vs suture R6 fixation) on QOL and pain were ambiguous (30,32). The study performed by Wassenaar et al R7 did not find any difference in post-operative pain or QOL comparing suture (absorbable or non- R8 absorbable) or tacker fixation. The Bansal study showed a reduction of early post-operative R9 pain and return to activity in favor of suture fixation compared to tacker fixation of the mesh. R10 Transfascial sutures were used in both groups. R11 R12 Tackers are usually non-absorbable, but are produced in absorbable material as well. Absorbable R13 tackers have been designed because the definitive fixation methods were thought to cause pain. R14 Absorbable tackers might be related with a lower tensile strength of fixation of the mesh to the R15 abdominal wall compared to non-absorbable tacks, the reason why the latter are more often R16 used. Nonetheless, this has only been proven in animal studies (36,37). R17 The shape and penetration depth of the fixation device probably plays a key role in tensile R18 R19 strength. Non-absorbable metal tacks might cause more intra-abdominal adhesions of viscera R20 to the tacks than absorbable tack (36,38) at the long term. On the other hand, at follow-up R21 until 6 months after the index surgery, some ‘absorbable tackers’ did not show any signs of R22 degeneration (38). A difference in post-operative pain between definitive and resorbable fixation R23 has never been determined. R24 R25 In conclusion, thorough registries of patients with incisional hernias who undergo surgical repair 7 R26 and of those who abstain from surgery are of great importance to learn more about the outcomes R27 of surgical and non-surgical management of incisional hernias. Comparing standardized surgical R28 techniques in randomized clinical trials is another necessary method to improve the quality of care R29 that we provide to patients with incisional hernias. R30 R31 A randomized trial is needed to know which patients are suitable for an endoscopic repair, the R32 natural course of an incisional hernia in asymptomatic patients, what surgical technique to R33 R34 choose and the effect on morbidity such as recurrence rate and quality of life. Authors initiated R35 the “INCH trial”, a randomized controlled trial and registry that started July 2012, in which they R36 aim to find an answer on some of these questions. R37 R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 97 R1 References R2 R3 1. Cassar K, Munro A. Surgical treatment of incisional hernia. Br J Surg 2002, May;89(5):534-45. R4 2. den Hartog D, Dur AH, Tuinebreijer WE, Kreis RW. Open surgical procedures for incisional hernias. Cochrane Database Syst Rev 2008(3):CD006438. R5 3. Rosch R, Junge K, Knops M, Lynen P, Klinge U, Schumpelick V. Analysis of collagen-interacting proteins R6 in patients with incisional hernias. Langenbecks Arch Surg 2003, Feb;387(11-12):427-32. R7 4. Llaguna OH, Avgerinos DV, Lugo JZ, Matatov T, Abbadessa B, Martz JE, Leitman IM. Incidence and R8 risk factors for the development of incisional hernia following elective laparoscopic versus open colon resections. Am J Surg 2010, Aug;200(2):265-9. R9 5. Nieuwenhuizen J, Kleinrensink GJ, Hop WC, Jeekel J, Lange JF. Indications for incisional hernia repair: R10 An international questionnaire among hernia surgeons. Hernia 2008, Jun;12(3):223-5. R11 6. Sajid MS, Bokhari SA, Mallick AS, Cheek E, Baig MK. Laparoscopic versus open repair of incisional/ R12 ventral hernia: A meta-analysis. Am J Surg 2009, Jan;197(1):64-72. 7. Forbes SS, Eskicioglu C, McLeod RS, Okrainec A. Meta-analysis of randomized controlled trials R13 comparing open and laparoscopic ventral and incisional hernia repair with mesh. Br J Surg 2009, R14 Aug;96(8):851-8. R15 8. Slim K, Nini E, Forestier D, Kwiatkowski F, Panis Y, Chipponi J. Methodological index for non-randomized R16 studies (minors): Development and validation of a new instrument. ANZ J Surg 2003, Sep;73(9):712-6. 9. Bageacu S, Blanc P, Breton C, Gonzales M, Porcheron J, Chabert M, Balique JG. Laparoscopic repair of R17 incisional hernia: A retrospective study of 159 patients. Surg Endosc 2002, Feb;16(2):345-8. R18 10. Bencini L, Sanchez LJ, Scatizzi M, Farsi M, Boffi B, Moretti R. Laparoscopic treatment of ventral hernias: R19 Prospective evaluation. Surg Laparosc Endosc Percutan Tech 2003, Feb;13(1):16-9. R20 11. Berger D, Bientzle M. Polyvinylidene fluoride: A suitable mesh material for laparoscopic incisional and parastomal hernia repair! A prospective, observational study with 344 patients. Hernia 2009, R21 Apr;13(2):167-72. R22 12. Berger D, Bientzle M, Müller A. Postoperative complications after laparoscopic incisional hernia repair. R23 Incidence and treatment. Surg Endosc 2002, Dec;16(12):1720-3. R24 13. Carbajo MA, Martp del Olmo JC, Blanco JI, Toledano M, de la Cuesta C, Ferreras C, Vaquero C. Laparoscopic approach to incisional hernia. Surg Endosc 2003, Jan;17(1):118-22. R25 14. Ceccarelli G, Patriti A, Batoli A, Bellochi R, Spaziani A, Pisanelli MC, Casciola L. Laparoscopic incisional R26 hernia mesh repair with the “double-crown” technique: A case-control study. J Laparoendosc Adv Surg R27 Tech A 2008, Jun;18(3):377-82. R28 15. Heniford BT, Ramshaw BJ. Laparoscopic ventral hernia repair: A report of 100 consecutive cases. Surg Endosc 2000, May;14(5):419-23. R29 16. Kirshtein B, Lantsberg L, Avinoach E, Bayme M, Mizrahi S. Laparoscopic repair of large incisional R30 hernias. Surg Endosc 2002, Dec;16(12):1717-9. R31 17. Koehler RH, Voeller G. Recurrences in laparoscopic incisional hernia repairs: A personal series and R32 review of the literature. JSLS 1999;3(4):293-304. R33 18. Kurmann A, Visth E, Candinas D, Beldi G. Long-term follow-up of open and laparoscopic repair of large incisional hernias. World J Surg 2011, Feb;35(2):297-301. R34 19. Liang MK, Subramanian A, Awad SS. Laparoscopic transcutaneous closure of central defects in R35 laparoscopic incisional hernia repair. Surg Laparosc Endosc Percutan Tech 2012, Apr;22(2):e66-70. R36 20. Moreno-Egea A, Bustos JA, Girela E, Aguayo-Albasini JL. Long-term results of laparoscopic repair of R37 incisional hernias using an intraperitoneal composite mesh. Surg Endosc 2010, Feb;24(2):359-65. 21. Motson RW, Engledow AH, Medhurst C, Adib R, Warren SJ. Laparoscopic incisional hernia repair with R38 a self-centring suture. Br J Surg 2006, Dec;93(12):1549-53. R39

98 | Chapter 7 22. Olmi S, Erba L, Magnone S, Bertolini A, Croce E. Prospective clinical study of laparoscopic treatment of incisional and ventral hernia using a composite mesh: Indications, complications and results. Hernia R1 2006, Jun;10(3):243-7. R2 23. Olmi S, Cesana G, Erba L, Croce E. Emergency laparoscopic treatment of acute incarcerated incisional R3 hernia. Hernia 2009, Dec;13(6):605-8. R4 24. van’t RM, Vrijland WW, Lange JF, Hop WC, Jeekel J, Bonjer HJ. Mesh repair of incisional hernia: Comparison of laparoscopic and open repair. Eur J Surg 2002;168(12):684-9. R5 25. Stickel M, Rentsch M, Clevert DA, Hernandez-Richter T, Jauch KW, Löhe F, Angele MK. Laparoscopic R6 mesh repair of incisional hernia: An alternative to the conventional open repair? Hernia 2007, R7 Jun;11(3):217-22. R8 26. Sturt NJ, Liao CC, Engledow AH, Menzies D, Motson RW. Results of laparoscopic repair of primary and recurrent incisional hernias at a single UK institution. Surg Laparosc Endosc Percutan Tech 2011, R9 Apr;21(2):86-9. R10 27. Verbo A, Petito L, Manno A, Coco C, Mattana C, Lurati M, et al. Laparoscopic approach to recurrent R11 incisional hernia repair: A 3-year experience. J Laparoendosc Adv Surg Tech A 2007, Oct;17(5):591-5. R12 28. Wolter A, Rudroff C, Sauerland S, Heiss MM. Laparoscopic incisional hernia repair: Evaluation of effectiveness and experiences. Hernia 2009, Oct;13(5):469-74. R13 29. Yannam GR, Gutti TL, High R, Stevens RB, Thompson JS, Morris MC. Experience of laparoscopic incisional R14 hernia repair in kidney and/or transplant recipients. Am J Transplant 2011, Feb;11(2):279-86. R15 30. Wassenaar E, Schoenmaeckers E, Raymakers J, van der Palen J, Rakic S. Mesh-fixation method and R16 pain and quality of life after laparoscopic ventral or incisional hernia repair: A randomized trial of three fixation techniques. Surg Endosc 2010, Jun;24(6):1296-302. R17 31. Bansal VK, Misra MC, Babu D, Singhal P, Rao K, Sagar R, et al. Comparison of long-term outcome and R18 quality of life after laparoscopic repair of incisional and ventral hernias with suture fixation with and R19 without tacks: A prospective, randomized, controlled study. Surg Endosc 2012, Dec;26(12):3476-85. R20 32. Bansal VK, Misra MC, Kumar S, Rao YK, Singhal P, Goswami A, et al. A prospective randomized study comparing suture mesh fixation versus tacker mesh fixation for laparoscopic repair of incisional and R21 ventral hernias. Surg Endosc 2011, May;25(5):1431-8. R22 33. Sauerland S, Walgenbach M, Habermalz B, Seiler CM, Miserez M. Laparoscopic versus open surgical R23 techniques for ventral or incisional hernia repair. Cochrane Database Syst Rev 2011(3):CD007781. R24 34. Cobb WS, Kercher KW, Heniford BT. Laparoscopic repair of incisional hernias. Surg Clin North Am 2005, Feb;85(1):91-103, ix. R25 35. Shankaran V, Weber DJ, Reed RL, Luchette FA. A review of available prosthetics for ventral hernia 7 R26 repair. Ann Surg 2011, Jan;253(1):16-26. R27 36. Duffy AJ, Hogle NJ, LaPerle KM, Fowler DL. Comparison of two composite meshes using two fixation R28 devices in a porcine laparoscopic ventral hernia repair model. Hernia 2004, Dec;8(4):358-64. 37. Hollinsky C, Kolbe T, Walter I, Joachim A, Sandberg S, Koch T, et al. Tensile strength and adhesion R29 formation of mesh fixation systems used in laparoscopic incisional hernia repair. Surg Endosc 2010, R30 Jun;24(6):1318-24. R31 38. Reynvoet E, Berrevoet F, De Somer F, Vercauteren G, Vanoverbeke I, Chiers K, Troisi R. Tensile strength R32 testing for resorbable mesh fixation systems in laparoscopic ventral hernia repair. Surg Endosc 2012, Sep;26(9):2513-20. R33 R34 R35 R36 R37 R38 R39

Laparoscopic incisional hernia repair: Influence of surgical technique on recurrence rate | 99 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39 PART II

Groin hernias

Chapter 8

EAES Consensus Development Conference

on endoscopic repair of groin hernias

M.M. Poelman B. van den Heuvel J.D. Deelder G.S.A. Abis N. Beudeker R.K.J. Bittner G. Campanelli D. van Dam B.J. Dwars H. Eker A. Fingerhut I. Khatov F. Kockerling J.F. Kukleta M. Miserez A. Montgomery R.M. Munoz Brands S. Morales Conde F.E. Muysoms M. Soltes W. Tromp Y. Yavuz H.J. Bonjer

Surg Endosc. 2013 Oct;27(10):3505-19 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

104 | Chapter 8 Introduction R1 R2

Groin hernia repair is one of the most common surgeries performed globally in more than 20 R3 R4 million people per year. (1; 2) The first surgeries for groin hernias were done in by the end R5 of the 16th century. (3; 4) Repairs that involved reduction and resection of the hernial sac and R6 enforcement of the posterior wall of the by approximating its muscular and fascial R7 components were done by the end of the 19th century. Utilization of prosthetic material was R8 introduced in the 1960’s, initially only in elderly patients with recurrent inguinal hernias. Favorable R9 long-term results of these mesh repairs allowed adoption of mesh repair in a larger group of R10 patients. At the present time, the majority of surgeons prefers mesh repair of inguinal hernias. R11 In the early 1980’s, minimally invasive techniques for groin hernia repair were first reported, R12 adding another modality to the management of these hernias. (4) Transperitoneal laparoscopic R13 and extraperitoneal endoscopic techniques, collectively coined ‘endoscopic surgery’, have been R14 developed. There is considerable variation of surgical techniques in endoscopic repair of groin R15 hernias rendering development of consensus prudent. R16 R17

The European Association of Endoscopic Surgery (EAES) initiated a consensus development R18 R19 conference with on endoscopic groin hernia surgery during its annual congress in 2012. The R20 aim of this conference was to provide practical guidelines employing available medical evidence R21 combined with the opinions of an expert panel and the membership of the EAES. The findings of R22 this conference are reported here. R23 R24 R25 Methods R26 R27 The coordinator of the consensus development conference (HJB) and two members of the R28 consensus panel (BvdH and MMP) selected a group of 14 surgeons, representing the European 8 R29 countries, with both clinical and scientific expertise in groin hernia surgery. Six medical scientists R30 supported this panel of experts. Key topics were presented, adapted and eventually approved by R31 the panel of experts. All topics were assigned to two experts and medical scientists. R32 R33 R34 The medical scientists performed a critical appraisal of the literature and selected the best available R35 evidence on each topic. A literature search was performed for each specific topic. All the articles R36 concerning this specific topic were reviewed and articles with the highest level of evidence were R37 selected. The level of evidence was assessed according to the Oxford classification (Table 1.) (5) R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 105 R1 The best available evidence was summarized. PubMed and the Cochrane database were used. R2 BvdH and MMP supervised the medical scientists and checked all the searches and summaries. R3 A summary of the best available evidence, including complete search and grading of the level of R4 evidence of each study, was completed and distributed to the experts allotted for that particular R5 topic two weeks before the first meeting in Amsterdam. R6 R7 R8 Table 1.Oxford Classification for levels of evidence (also see www.cebm.net) Level Therapy/ Prognosis R9 Prevention, Aetiology/Harm R10 1a Systematic Review (with homogeneity) of RCTs SR of inception cohort studies; validated in R11 different populations R12 1b Individual RCT (with narrow Confidence Interval) Individual inception cohort study with > 80% follow-up; validated in a single population R13 1c All or none All or none case-series R14 2a SR (with homogeneity) of cohort studies SR (with homogeneity) of either retrospective R15 cohort studies or untreated control groups in R16 RCTs 2b Individual cohort study (including low quality Retrospective cohort study or follow-up of R17 RCT; e.g., <80% follow-up) untreated control patients in an RCT. R18 2c “Outcomes” Research; Ecological studies “Outcomes” Research R19 3a SR (with homogeneity) of case-control studies R20 3b Individual Case-Control Study 4 Case-series (and poor quality cohort and case- Case-series (and poor quality prognostic cohort R21 control studies) studies) R22 5 Expert opinion without explicit critical appraisal, Expert opinion without explicit critical appraisal, R23 or based on physiology, bench research or “first or based on physiology, bench research or “first principles” principles” R24 R25 R26 First statements were formulated (by HJB) in preparation of the first meeting. These statements R27 and the summary of the best available evidence on each topic were given to the expert panel at R28 the first meeting. R29 R30 On April 20th 2012, 14 members of the expert panel attended a full day meeting. The coordinator R31 of the consensus development conference HJB chaired the meeting. Each topic was discussed R32 individually. Discussion was initiated by presenting the summary of the reviewed literature R33 pertaining to that specific topic by one of the medical scientists. The levels of evidence of R34 the reviewed manuscripts as determined by the medical scientists were discussed and either R35 confirmed or modified. R36 The statement was submitted to all members of the expert panel for acceptance. Statements R37 were accepted, modified or rejected. Subsequently, each statement was discussed and the level of R38 R39

106 | Chapter 8 agreement was determined, if the majority agreed, the statement was accepted in the consensus. R1 The statements and levels of evidence were distributed among all members of the expert panel R2 after the meeting for approval. After approval, the topics and statements were posted on the R3 R4 EAES website prior to the annual conference of the EAES on June 22 2012 in Brussels. R5 The members of the expert panel presented all topics, statements and associated level of evidence R6 to an audience of attendees of the EAES conference. Voting pads allowed all present to vote R7 in favour or against each statement. The level of consensus was determined according to the R8 classification shown in table 2. R9 The conference was recorded and was posted on the EAES-website after the congress was R10 held. EAES members could vote in favour or against the statement through a secured link. Two R11 reminders to vote were sent by email via the general EAES secretary. R12 R13 Table 2. Classification of consensus R14 Strength of consensus Percentage of agreement R15 Strong consensus >95% of participants R16 Consensus 75-95% of participants R17 Majority 50-75% of participants No consensus <50% of participants R18 R19 R20 R21 Results R22 R23 One thousand eighty-one delegates from 82 countries attended the EAES congress in Brussels in R24 2012. Of these, between 92 and 164 surgeons voted during the consensus conference. After the R25 conference was posted on the EAES-website, 17 surgeons voted (at least for some statements) R26 online. R27 The level of evidence (LoE), as determined by the expert panel, will be provided after each R28 statement. The level of consensus (LoC/ table 2) will be provided, including the votes in favour of 8 R29 the statement, the total amount of votes and the calculated percentage. R30 R31 Factors predisposing to developing groin hernias R32 The impact of predisposing factors on the development of groin hernias is under debate. R33 R34 Many clinicians assume that occasional lifting, constipation and prostatism increase the risk for R35 developing groin hernias. However, evidence is lacking. (6; 7) R36 A patent processus vaginalis does predispose for developing a groin hernia. (8) Patients who R37 have ascites, who are treated with intra-abdominal dialysis, who suffer from COPD and those R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 107 R1 who perform long-term heavy work have an increased risk for developing a groin hernia due R2 to an elevated intra-abdominal pressure. (6; 7) Surgery in the lower abdomen such as an open R3 or prostatectomy might cause a groin hernia. (6; 7) R4 R5 Hernias of the abdominal wall represent weakening of the muscular and fascial layers of the R6 abdominal wall. Collagen is an important cross-link providing strength to such tissues. Therefore, R7 deficiencies of collagen metabolism may cause hernias. There are twelve types of collagen in R8 R9 the human body; the proper balance between these individual collagen types is essential to R10 the strength of the collagen rich tissues. Changes in the collagen metabolism can either be due R11 to external factors like smoking, or have a genetic predisposition. (6; 7) An altered collagen R12 metabolism manifested by a decreased type I:III collagen ratio seems to be the underlying biologic R13 source of abdominal wall hernia formation. (9) R14 Patients with an abdominal aortic aneurysm (AAA’s) have an increased propensity for abdominal R15 wall hernia development. In a recent meta-analysis (10) the correlation between AAA’s and R16 abdominal wall hernias was confirmed. The study compared the incidence of incisional and R17 inguinal hernias in patients with AAA’s to patients with aorto-iliac occlusive disease (AOD) and R18 found a relative risk of inguinal hernia of 2.3 (odds-ratio, 2.30; 95% CI, 1.52-3.48; p<0.0001). R19 Patients with a decreased type I:III collagen metabolism and patients with an abdominal aortic R20 aneurysm are thought to share a systemic connective tissue defect, affecting the structural R21 integrity of the aortic and the abdominal wall. The exact pathogenesis is unknown. R22 R23 R24 In a Swedish cohort study (11) on 1072 HIV-infected male patients on anti-retroviral therapy, an R25 increased incidence of abdominal wall hernias was reported. The underlying mechanism/cause of R26 this finding is unknown. R27 R28 Statements R29 1. Occasional lifting, constipation and prostatism do not predispose to the development R30 of groin hernia. R31 LoE: 3 LoC: majority, 68/110=62% R32 2. In patients suffering from aneurysmal disease, the incidence of groin hernia is increased. R33 LoE: 3 LoC: majority, 60/115= 52% R34 R35 Assessment of groin hernia R36 In daily practice, the majority of groin hernias can be diagnosed accurately by physical examination. R37 Imaging studies are only indicated when the presence of a groin hernia is unclear or when the R38 R39

108 | Chapter 8 clinician is unsure whether the swelling in the groin is caused by a hernia. (12; 13) However, in R1 case of groin pain without a swelling at clinical presentation, the diagnosis of a groin hernia by R2 physical examination can be challenging (14) and additional imaging modalities may be necessary R3 R4 to identify the actual groin pathology. (15) Herniography, radiography of the pelvic area after R5 intra-peritoneal injection of radio-opaque dye, has been the standard imaging procedure since R6 1967. (16) However, this is an invasive procedure with inherent risk of visceral of vascular damage. R7 A recent review showed an overall sensitivity rate ranging from 81 to 100% and specificity rate R8 from 92 to 98.4%. Other non-invasive imaging modalities such as ultrasound, CT-scan and MRI R9 have been evaluated. R10 A non-contrast CT-scan has an overall accuracy of 94%. (17) A small study (18) confirms the R11 additional value of MRI when the herniography is unclear in an occult groin hernia. Correlation R12 with surgical findings showed ultrasound to have a sensitivity of 33% and a specificity of 100%. R13 (19; 20) R14 CT-scan and MRI have the advantage above ultrasound and herniography in diagnosing other R15 causes of groin pathology. Ultrasound has a high specificity, is cheap and is therefore considered R16 the most cost effective imaging modality in patients with groin hernia. R17 R18 R19 It is considered difficult to determine whether an inguinal hernia is direct or indirect during physical R20 examination. (21-23) Some surgeons prefer a precise and detailed preoperative evaluation of the R21 type of inguinal hernia and advocate the concept of individualized inguinal hernia repair. (15; 24- R22 29) However, knowledge of the type of inguinal hernia rarely modifies the indication for surgery R23 and little importance is been given to preoperative differentiation of inguinal hernia type. In R24 accordance, the majority of the expert panel did not believe that pre-operative knowledge of the R25 type of hernia would change their surgical approach. R26 R27 Statements R28 3. In case of clear clinical diagnosis of inguinal hernia, no additional imaging studies are 8 R29 necessary. R30 LoE: 2C LoC: consensus, 137/147=93% R31 4. When a groin hernia is suspected but clinical findings are equivocal, the first step in R32 imaging is dynamic ultrasonography, followed by dynamic MRI. R33 R34 LoE: 2C LoC: consensus, 138/149=93% R35 5. Ultrasonography and MRI have a high sensitivity and specificity considering the R36 detection of an occult inguinal hernia and have replaced herniography as a diagnostic R37 instrument. R38 LoE: 2C LoC: consensus, 136/149=91% R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 109 R1 6. CT can be a useful adjunct for the detection of an occult groin hernia. R2 LoE: 3 LoC: majority, 112/152= 74% R3 7. Physical examination does not allow distinguishing direct i.e. medial from indirect i.e. R4 lateral inguinal hernias. R5 LoE: 2 LoC: majority, 103/154=67% R6 R7 Operative or conservative approach of groin hernias and selection of endoscopic R8 R9 technique. R10 The general strategy toward groin hernias is surgical repair. The presenting symptom of a groin R11 hernia is either discomfort or pain in the groin in two-thirds of all patients. (30) One third of all R12 patients has no symptoms at clinical presentation, but only a sign of a non-tender bulge in the R13 groin. The rationale to recommend surgery is to prevent visceral incarceration and subsequently R14 ischemia (strangulation). However, little is known about the natural history of untreated groin R15 hernias. (31) Recently, two large randomized controlled studies have been published (32; 33) R16 to analyze the natural course of asymptomatic inguinal hernias. These studies concluded that R17 watchful waiting was safe in asymptomatic inguinal hernias. However, a later study showed that R18 the majority of patients with an asymptomatic inguinal hernia eventually becomes symptomatic R19 and concluded that the evidence for a watchful waiting policy is lacking. (34) The rationale for R20 surgery in inguinal hernias is, therefore, treatment of current or future symptoms and not to R21 prevent incarceration. R22 Considering that most patients with an asymptomatic groin hernia eventually become symptomatic, R23 R24 an occult contralateral hernia, discovered during endoscopic repair of a symptomatic unilateral R25 hernia, can be repaired during the same surgical procedure. This can only be done when this R26 option has been discussed prior to surgery and informed consent was obtained. In absence of R27 a groin hernia, prophylactic mesh-placement on the contralateral side in endoscopic repair of a R28 symptomatic unilateral hernia is not advisable. R29 R30 Femoral hernias seem to incarcerate significantly more than inguinal hernias. The actual risk of R31 incarceration of femoral hernias has only been described in observational cohort studies, but R32 shows a 7-8 fold increase compared to inguinal hernias. (31; 35-38) The rationale for surgery in R33 femoral hernias is therefore to prevent incarceration. R34 R35 Endoscopic repair can be done for all groin hernias, inguinal and femoral, unilateral and bilateral, R36 primary and recurrent. The expert panel states that there are no absolute contra-indications for R37 endoscopic repair in adolescents, age 14 to 18 years. Endoscopic groin hernia in complicated R38 R39

110 | Chapter 8 situations, such as in patients after radical prostatectomy or cystectomy, in patients with a scrotal R1 hernia, ascites, on and redo endoscopic repairs, should only be performed by a R2 surgeon that has a high level of experience in endoscopic groin hernia repair. R3 R4 R5 The two major endoscopic techniques are transabdominal preperitoneal repair (TAPP) and total R6 preperitoneal repair (TEP). In the best available evidence (39; 40), no technique seems to be R7 superior to the other with regards to outcomes and complication rates. Both techniques were R8 associated with similar operative time, postoperative complications, postoperative pain, time R9 to return to work, and recurrences. TAPP was associated with a slightly longer hospital stay R10 compared with TEP. R11 R12 Endoscopic groin hernia repair is favored over open groin hernia repair in certain patients. R13 Endoscopic groin hernia repair is associated with less post-operative pain than open repair. (41- R14 44) This difference in pain seems to disappear during the first 6 weeks after surgery. Young R15 active adults benefit mostly from endoscopic groin hernia repair since they gain most from early R16 convalescence. It is therefore stated that young active adults with a groin hernia are preferably R17 repaired with an endoscopic technique. Endoscopic surgery is also preferred in patients with R18 R19 a recurrent groin hernia after open repair. (40) The posterior route is free of scar tissue and R20 therefore the groin can be reached more easily with an endoscopic approach. R21 In patients with bilateral groin hernias, the expert group stated that endoscopic repair is ideal R22 because both groins can be reached using two or three small incisions, whereas in open repair R23 one large incision in each groin is necessary. R24 R25 Statements R26 Recurrent groin hernia R27 8. Endoscopic surgery is preferred in patients with a recurrent groin hernia after open R28 repair. 8 R29 LoE: 1B LoC: strong consensus, 151/158=96% R30 9. Redo endoscopic repair is only feasible, when the surgeon has a high level of experience R31 in endoscopic groin hernia repair. R32 LoE: 5 LoC: consensus 109/134=81% R33 R34 Bilateral groin hernia R35 10. Especially in bilateral groin hernia endoscopic surgery is an excellent approach R36 LoE: 5 for TEP/ 2B for TAPP LoC: strong consensus, 154/161=96% R37 R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 111 R1 11. Concerning the repair of a bilateral hernia, there is no clear advantage of TEP over TAPP R2 or vice versa. R3 LoE: 1A LoC: majority, 105/142=73% R4 12. When an occult contralateral hernia is discovered during endoscopic repair of a R5 symptomatic unilateral hernia, the occult and the symptomatic hernia can be repaired R6 in the same surgical procedure. R7 LoE: 5 LoC: strong consensus, 148/154=96% R8 R9 13. In absence of a groin hernia, prophylactic mesh-placement on the contralateral side in R10 endoscopic repair of a symptomatic unilateral hernia is not advisable. R11 LoE: 5 LoC: consensus, 124/138=90% R12 Endoscopic repair in a complex situation R13 14. In complex situations*, endoscopic hernia repair should only be considered when the R14 surgeon has a high level of experience in endoscopic groin hernia repair. R15 LoE: 5 LoC: consensus, 135/152: 89% R16 *The following situations are considered to be highly complex: patients after radical R17 prostatectomy or cystectomy, and patients with a scrotal hernia, ascites, previous mesh R18 repair or peritoneal dialysis. R19 Endoscopic repair in the young individual R20 15. Young active adults with a groin hernia are preferably repaired with an endoscopic R21 technique. R22 LoE: 1A LoC: consensus, 112/148=76% R23 R24 16. There are no absolute contraindications for endoscopic repair in adolescents; age 14 to R25 18 years. R26 LoE: 5 LoC: majority, 96/150=64% R27 Endoscopic repair of femoral hernias R28 17. Endoscopic repair is the preferred surgical approach in case of a femoral hernia. R29 LoE: 5 (men/ 2C (women) LoC: consensus, 108/144=75% R30 R31 Endoscopic repair of strangulated hernia R32 The definitions of the terms strangulation and incarceration vary. The EAES consensus group R33 adheres to the following definition: Strangulation to indicate that there is a bulge in the hernia R34 sac, but it is reducible. The term incarceration is used for a non-reducible bulge in the groin R35 In case of strangulation or incarceration, the intra-abdominal cavity should be inspected, followed R36 by either TEP or TAPP. (45) Incarcerated groin hernias should be operated on urgently to prevent R37 for ischemia of the incarcerated viscera. R38 R39

112 | Chapter 8 Some surgeons dread the use of a mesh in emergency hernia repair, particularly when a bowel R1 resection is required, because of the fear for a mesh infection. However, there is insufficient R2 evidence to avoid mesh repair in these situations routinely. Recent studies (46; 47) showed few to R3 R4 no mesh infections in patients who underwent during an emergency endoscopic R5 procedure. R6 A recently performed trial (48) randomized patients with spontaneously reduced strangulated R7 groin hernias to either laparoscopic inspection of the hernia sac and abdominal cavity or to open R8 inspection of the hernia sac with or without explorative laparotomy (at the surgeon’s discretion). R9 In the laparoscopy group, 2 out of 21 patients had resections of a necrotic ileal bowel loop during R10 abdominal inspection. In the open group, 4 out of 20 patients had explorative laparotomy with R11 2 out of 4 bowel resections. One patient in the open group had a delayed laparotomy because R12 of missed bowel ischemia. R13 Overall, the endoscopic approach of incarcerated and strangulated groin hernias allows for R14 laparoscopic inspection of the intra-abdominal cavity in all patients, hence could prevent for R15 missed bowel ischemia. The endoscopic repair is therefore the preferred approach. R16 R17

Statements R18 R19 8. Repair of incarcerated, non-reducible, groin hernias has to be done urgently and can be R20 performed with an endoscopic technique. R21 LoE: 2A LoC: consensus, 124/155= 81% R22 9. When performing an endoscopic repair, the abdominal cavity should be inspected R23 followed by either TAPP or TEP. R24 LoE: 5 LoC: consensus, 113/123=92% R25 10. Mesh placement during surgery for strangulated groin hernia is possible in clean- R26 contaminated situations; i.e. in case of a bowel resection. R27 LoE: 2A LoC: majority, 103/150=69% R28 11. In suspicion of a strangulated groin hernia, a laparoscopic approach is preferred. 8 R29 LoE: 5 LoC: majority, 109/149=73% R30 R31 Endoscopic repair of sportsman’s hernia R32 Among professional athletes, groin pain is a common injury. Causes for chronic groin pain are R33 R34 lumbar spine problems such as compression syndrome and herniated lumbar disc, leg length R35 differences, tendinitis of the adductor muscle, osteitis pubis, prostatitis and sportman’s hernia. In R36 athletes with chronic groin pain, a sportman’s hernia can be diagnosed only when other causes R37 have been excluded. (49) Because of the large differential diagnosis of groin pain in athletes, it R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 113 R1 is extremely important to evaluate each patient in whom a sportsman’s hernia is suspected in a R2 multidisciplinary setting. R3 Various imaging techniques are used to diagnose a sportman’s hernia, or exclude other causes R4 of groin pain. (50) The expert panel agreed that MRI is the preferred imaging technique, because R5 of its capacity to differentiate between several groin pathologies. MRI has the advantage to R6 work with magnetic fields instead of Xrays, but is expensive and has never been proven the best R7 technique to diagnose groin hernias. R8 R9 R10 Several studies have been undertaken over the past few years to define the best treatment R11 method for sportsman’s hernia. In a prospective randomised setting, the endoscopic TEP mesh R12 placement was compared with conservative therapy (i.e. rest, physiotherapy, steroid injections R13 and oral anti-inflammatory analgesics) in 60 athletes with a groin hernia. (51) This study reported R14 that operative repair was more effective than non-operative treatment for chronic pain after R15 1 up to 12 months of follow up (p<0.001). Ninety per cent of the patients who underwent R16 surgery returned to sports activities after 3 months compared to 27% in the conservative group R17 (p<0.001). Two studies (50; 52) have treated athletes with chronic groin pain unresponsive to R18 conservative treatment with TEP. In these study groups, 93% to 100% returned to full sports R19 activity three months after TEP repair. R20 R21 Statements R22 12. A multidisciplinary team should evaluate possible sportsman’s hernia in order to exclude R23 R24 other causes of groin pain such as lumbar spine problem (compression syndrome, R25 herniated lumbar disc), leg length differences, tendinitis of the adductor muscle, osteitis R26 pubis or prostatitis. MRI is the preferred imaging modality. R27 LoE: 5 LoC: consensus, 141/161=88% R28 13. Endoscopic placement of a mesh in the groin is effective in athletes with a sportman’s R29 hernia. R30 LoE: 1B LoC: consensus, 129/147=88% R31 R32 Antibiotic prophylaxis R33 There is very little evidence for the use of antibiotics during endoscopic groin hernia repair. (53) R34 In open groin hernia repair, the effectiveness of antibiotic prophylaxis in reducing postoperative R35 wound infection rates has been studied extensively. In 2012, a large Cochrane review was R36 published concerning this subject. It included 7843 patients from 17 RCTs. It was concluded R37 that no universal recommendation for antibiotic prophylaxis could be given; neither can it be R38 R39 recommended against when high infection rates are observed. (54)

114 | Chapter 8 Statements R1 14. There is not enough evidence to support the routine use of prophylactic antibiotics in R2 elective endoscopic groin repair. R3 R4 LoE: 5 LoC: consensus, 123/162=76% R5 R6 Procedural and technical aspects of endoscopic groin hernia repair. R7 The particular technical details of TEP and TAPP groin hernia repair are beyond the aim of this R8 manuscript. The choice and fixation of the mesh and how to approach the absence of a hernia R9 sac during surgery will be discussed in this chapter. R10 R11 To evaluate the type of mesh used during endoscopic groin hernia repair, a meta-analysis of R12 lightweight-mesh versus heavyweight-mesh in both TEP and TAPP inguinal hernia repair was R13 performed. (55) Eight randomized clinical trials were included (56-62), a total of 1667 hernias R14 in 1592 patients were analysed. The mean study follow-up was between 2 and 60 months. No R15 significant effect on recurrence, chronic pain, postoperative pain, seroma formation or return to R16 work was found and both meshes appeared to result in similar long- and short-term postoperative R17 outcomes. Future long-term analysis of post-operative chronic pain may guide surgeons’ selection R18 R19 of mesh weight for endoscopic groin hernia repair. R20 R21 Mesh fixation technique is a frequently studied topic since post-operative pain has become one of R22 the major outcomes in inguinal hernia surgery. In TAPP repair the mesh is usually fixed with glue, R23 tackers or staples. In TEP repair, the mesh is not fixed at all, or fixed with glue, tackers or staples. R24 Several studies have been published concerning the difference between glue and tacker fixation R25 in TAPP hernia repair with regard to the incidence of recurrences. (63-67) The type of fixation R26 did not influence the recurrence rate. Also, the type of fixation did not seem to influence acute R27 or chronic pain. (64-68) Some studies suggest that tacker fixation may lead to higher acute and R28 chronic pain scores but other studies repudiate this. (66) 8 R29 Three groups recently performed meta-analyses of the influence of fixation versus non-fixation R30 of the mesh in TEP repair. (69-71) Only one group reported a difference in chronic post-operative R31 pain favoring the non-fixation group. (71) The other two (69; 70) did not find any difference in R32 recurrence rate or (chronic) pain. A recent randomized controlled trial (that was not included R33 R34 in these meta-analyses) (72) compared post-operative pain between fixation and non-fixation R35 of the mesh and did not show any difference in acute or chronic pain. Moreover, the incidence R36 and amount of post-operative pain is also likely to be influenced by the number and location of R37 tackers/staples. R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 115 R1 The expert group agreed that diverse types of inguinal hernias (i.e. direct vs indirect and large R2 vs small hernias) should be distinguished and treated in a different way. Randomised controlled R3 trials have not differentiated between large and small hernias; the use of a lightweight mesh with R4 or without fixation of the mesh in case of a large direct (medial) hernia might lead to a higher R5 recurrence rate. R6 R7 A prevalent phenomenon during endoscopic repair of a groin hernia is absence of a hernia sac. R8 R9 Patients present with a bulge in the groin, but during surgical exploration no sac is found. Even R10 when a sac is absent, herniation through the abdominal wall is not excluded. Preperitoneal fatty R11 tissue could protrude through an insufficient fascia transversalis as a direct hernia or through R12 the internal ring along the spermatic cord as an indirect hernia. Inguinal lipomas are therefore R13 considered to be a pitfall in hernia surgery. (73) The incidence of an inguinal lipoma is around R14 20% and might be related to BMI. (74-76) R15 R16 Statements R17 15. Sufficient overlap of the mesh is more important than fixation of the mesh. R18 LoE: 5 LoC: consensus, 116/141=82% R19 16. There is currently not enough evidence supporting the general use of lightweight mesh R20 over heavyweight mesh in endoscopic groin hernia repair. R21 LoE: 1A LoC: consensus, 127/147=86% R22 17. The mesh in groin hernia repair measures minimally 15x10cm. R23 R24 LoE: 5 (TEP)/ 2C (TAPP) LoC: consensus, 136/153=89% R25 18. The use of a heavy weight mesh, larger mesh size, mechanical fixation and reduction of R26 the dead space (i.e. fixation of the transversalis fascia) could be considered in patients R27 with a large medial i.e. direct hernia. R28 LoE: 5 LoC: consensus, 121/142=85% R29 19. Tacker or suture fixation for unilateral groin hernia (with the exception of large direct R30 inguinal hernias) should be avoided. R31 LoE: 5 LoC: majority, 104/158=66% R32 20. In absence of a preperitoneal hernia sac, an active search for herniating lipomas should R33 be done. R34 LoE: 5 LoC: consensus, 136/172=79% R35 21. Herniated adipose tissue present in the internal ring should be reduced. R36 LoE: 5 LoC: consensus, 125/135=93% R37 R38 R39

116 | Chapter 8 Complications of endoscopic groin hernia repair R1 Complications after endoscopic groin hernia repair are widely described. The most common R2 short-term complication is formation of a haematoma or a seroma. The average incidence of R3 R4 haematoma reported in several randomized controlled trials lies around 8%. (40; 42; 77-85) R5 The incidence of a post-operative seromas after endoscopic repair is approximately 7%. It is of R6 great importance to inform patients about the possibility of seroma formation, as seroma is not R7 a seldom side effect. Patients might confuse the swelling formed by the seroma as a persistent R8 groin hernia and might conclude that surgery has failed. However, seroma formation most often R9 lacks clinical significance or clinical relevance. Therefore, all panel members agreed that when R10 seroma formation occurs, generally, there is no need for aspiration. R11 R12 In contrast to complications such as haematoma and seroma, wound infection after endoscopic R13 repair occurs rarely and reported rates are around 1% (40; 42; 77; 79-83; 85-87) Also mesh R14 infection occurs seldom. A Cochrane review shows that only one mesh infection occurred in 2179 R15 patients who underwent endoscopic groin hernia repair. (40) The expert panel agrees that in case R16 of a mesh-infection, removal of the mesh is generally not necessary. R17 R18 R19 A frequently mentioned drawback of laparoscopic repair of an inguinal hernia is the possible R20 collateral damage of vital adjacent structures such as bowels or vessels. However, no evidence for R21 such an increased risk of serious collateral damage is supported by the literature. A large meta- R22 analysis of 2005 comparing laparoscopic inguinal hernia repair versus open repair included about R23 3500 repairs and analyzed the incidence of collateral damage. In the laparoscopic group (TAPP/ R24 TEP), an incidence was documented of 0.1% of intra-operative bowel lesions, versus 0.06% in R25 the open group. This difference was not significant. The incidence of vascular damage in the R26 laparoscopic group was 0.09% versus none in the open. This difference was also not significant. R27 (79) R28 8 R29 The most common long-term complications are recurrence and (chronic) pain. The recurrence rate R30 after endoscopic surgery is consistently low and varies between 0-4%. (77; 88-90) Chronic pain R31 on the other hand is a more common adverse outcome of (endoscopic) hernia repair and lacks a R32 uniform definition. Incidences therefore vary widely, and rates as high as 25% are reported. (77) R33 R34 The expert panel consented that a proper meta-analysis of the vast amount of studies is needed. R35 R36 Quality of life and incidence of (acute) pain differ from one technique to the other and might be R37 influenced by fixation of the mesh and type of mesh. Most studies comparing the effect of open R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 117 R1 and laparoscopic repair of inguinal hernia on quality of life and pain, favor the latter, because of a R2 reduction in acute pain. (77; 91-94) However, the difference in post-operative pain scores in favor R3 of the laparoscopic approach diminishes over time. R4 R5 Recently more attention is paid to the effect of mesh repair on male fertility. Testicular atrophy, R6 due to impaired vascularization, and hydrocele are identified as long-term complications after R7 inguinal hernia repair. A recent study suggests that the use of a mesh causes impaired sperm- R8 R9 motility. (59) However, in a large epidemiologic study no association has been found between R10 inguinal hernia repair and increased incidence of infertility. (95) R11 R12 Statements R13 Short-term complications R14 22. Infections of the mesh rarely occur after endoscopic groin hernia repair. In case of mesh- R15 infection, removal of the mesh is generally not necessary. R16 LoE low rates: 1A LoC: majority, 103/150=69% R17 23. Formation of a seroma is a frequent occurrence after endoscopic groin hernia repair but R18 lacks clinical relevance or significance in most cases. It is advised to explain the possibility R19 of seroma formation to the patient pre-operatively to prevent anxiety. R20 LoE: 5 LoC: consensus, 146/155=94% R21 24. In general, the aspiration of a seroma is not advised. R22 LoE: 5 LoC: consensus, 129-157=82% R23 R24 25. Endoscopic surgeons should strive for wound infection rates below 2% after endoscopic R25 groin hernia repair. R26 LoE: 5 LoC: consensus, 102/111=92% R27 Long-term complications R28 26. Endoscopic surgeons should strive for symptomatic recurrence rates below 5% five R29 years after endoscopic groin hernia repair. R30 LoE: 5 LoC: consensus, 130/142=92% R31 27. Endoscopic surgeons should strive for severe chronic groin pain rates below 2% five R32 years after endoscopic groin hernia repair. R33 LoE: 5 LoC: consensus, 99/120=83% R34 28. Mesh repair in general does not seem to cause infertility in males. R35 LoE: 2C LoC: consensus, 133/145=92% R36 R37 R38 R39

118 | Chapter 8 Postoperative considerations in endoscopic groin hernia repair R1 The general approach towards physical restrictions after groin hernia repair differs considerably. R2 (96) Many surgeons and general practitioners recommend a few weeks of rest, including no R3 R4 driving, working or lifting. However, those recommendations seem to depend more on local R5 tradition than clear evidence and therefore need to be reconsidered. (97) R6 Studies failed to show any disadvantageous effect of a short period of convalescence with regard R7 to the development of a recurrence. (98-102) Early and active encouragement of patients after R8 groin hernia repair is associated with shortened convalescence and earlier return to work. (101) R9 Hand and foot reaction times return to pre-operative levels 7-10 days after surgery. (103; 104) R10 R11 The value of follow-up after inguinal hernia repair is unclear. Most studies on this subject stress R12 the importance of prolonged follow-up for quality assessment of inguinal hernia surgery. These R13 studies use postal questionnaires to select patients with a suspected recurrence with varying R14 degrees of success. (105-107) No studies were found on the need for regular check-ups after R15 inguinal hernia repair, to detect asymptomatic recurrences or prevent incarceration. Therefore, R16 routine follow-up after groin hernia surgery lacks medical evidence. R17 R18 R19 Quality assessment after endoscopic inguinal hernia surgery consists of two long-term R20 complications; recurrence and pain. A variety of questionnaires and tools are being used to assess R21 the quality of life (QoL) and pain after inguinal hernia repair. R22 Traditionally, QoL-measurements after surgery were conducted using the generic Short Form-36 R23 (SF-36). (108) The SF-36 is thought to be an adequate tool to measure QoL in patients over time, R24 but it is too extended and universal to measure specific complaints after a specific treatment. R25 In addition to general health related quality of life instruments as the SF-36, disease specific R26 instruments focus on particular health conditions and are useful to detect the changes resulting R27 from specific treatment. The Carolina Comfort Scale (CCS) was developed as a disease specific R28 questionnaire for evaluating the QoL after the mesh hernia repair. (109) It evaluates the sensation 8 R29 of the mesh, pain and movement limitations in different aspects of common daily life. Another R30 disease specific questionnaire has recently been proposed (110), but it has not been validated yet. R31 The expert-panel agreed that an internationally accepted hernia-specific questionnaire to monitor R32 pain and discomfort after inguinal hernia repair is necessary. R33 R34 R35 For the evaluation of pain, the Visual Analogue Scale (VAS) is often used, although the Verbal R36 Rating Scale (VRS) might be better for post-herniorrhaphy pain assessment. (111) The Visual R37 Analogue Scale (VAS) for pain can be used when specific cut-off points are used to define mild, R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 119 R1 moderate and severe pain. Another questionnaire that has been used for pain-assessment is R2 the Inguinal Pain Questionnaire that has been proven a reliable instrument to assess pain after R3 inguinal hernia repair. (112) R4 R5 Statements R6 Patient encouragement / advise R7 29. Active encouragement after groin hernia repair is associated with shortened R8 R9 convalescence. R10 LoE: 3 LoC: consensus, 86/110=78% R11 30. Early activity after groin hernia repair does not seem to increase recurrence rates. R12 LoE: 3 LoC: consensus, 125/159=79% R13 Follow up R14 31. Routine follow-up after (endoscopic) groin hernia repair is not necessary*. R15 LoE: 5 LoC: consensus, 67/126=53% R16 *Consensus Conference Brussels: follow-up is necessary to assess incidence of recurrence and R17 chronic pain. R18 Quality of life R19 32. Quality of life after endoscopic hernia repair is generally excellent in most patients. R20 LoE: 1A LoC: consensus, 138/153=88% R21 R22 Educational, organizational and financial aspects of endoscopic groin hernia repair R23 R24 Competency in surgery is of great importance for patient safety. In endoscopic surgery of groin R25 hernias, competency has not been consistently defined. Hence, it is very difficult to determine the R26 criteria for reaching full competency. Endoscopic groin hernia repair is considered more difficult R27 than open groin hernia repair. The number of procedures needed to reach full competency R28 (formerly known as learning curve) is dependent on several factors such as previous experience R29 and type of training method. R30 The existing literature reflects mostly series of hernia surgeries performed by a single surgeon or a R31 small group of surgeons who adopted the technique of endoscopic surgical repair of hernias in a R32 non-structured fashion. The results of individual surgeons have been analysed in large retrospective R33 (113-115) and prospective studies. (116; 117) These studies showed significant reduction of R34 operating times, conversion rates and complication rates after 30 to 100 TEP procedures and R35 50 to 75 TAPP procedures. These studies reveal that the number of cases required to accomplish R36 competency is determined by various factors such as previous experience with other minimally R37 invasive procedures and experience in open groin hernia surgery. R38 R39

120 | Chapter 8 An American group (118; 119) demonstrated that surgeons in training reach competence R1 after fewer cases, in a structured educational programme. Development of structured training R2 programs is therefore mandatory to improve the efficacy of educational modules and increase R3 R4 patient safety. R5 R6 Clear evidence supporting centralisation of hernia repair in specialized hospitals is not available. R7 However, one study (118) demonstrated that centralisation of hernia repair within one hospital R8 by referring all patients with hernias to a single dedicated surgeon resulted in fewer wound R9 infections (5.9% to 0.45%, p <0.005), fewer systemic complications (2.05% to 0.45%, p < 0.05) R10 and lower recurrence rates (4.6% to 0.45%, p < 0.001). R11 The use of evidence-based protocols for hernia repair result in lower perioperative complications R12 rates (2.16%) and lower recurrences rates (0.78%). (120) These results favour specialization in R13 and centralization of hernia care. R14 R15 Endoscopic groin hernia repair is more expensive compared to open groin hernia repair. The R16 increased costs are particularly due to the need of special equipment and general anaesthesia. R17 Costs of disposable devices and operating time can be calculated accurately while determination R18 R19 of costs of personnel and amortization of non-disposable equipment is more difficult. Calculation R20 of indirect costs is even more complex, because methods of estimating lost income vary. In the R21 available literature, the direct medical costs of laparoscopic inguinal hernia repair were higher than R22 those of open repair. (41; 77; 78; 91; 121-133) When including societal costs, total costs were R23 often similar or lower after endoscopic repair. (6; 94; 134-138) Costs will become progressively R24 important in healthcare. Overall calculation of costs however is very complex and is therefore R25 prone to bias. R26 R27 Statements R28 Training and competency in endoscopic groin hernia repair 8 R29 33. Endoscopic groin hernia repair is considered to be more complex than open groin hernia R30 repair. R31 LoE: 2C LoC: consensus, 115/142=81% R32 34. Broad implementation of a structured educational program in endoscopy is recommended R33 R34 to familiarize surgeons in training with endoscopic surgery and to prevent rare but R35 serious complications of vascular damage or bowel perforation. R36 LoE: 5 LoC: strong consensus, 126/133=95% R37 R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 121 R1 35. Numbers needed to reach competence in endoscopic groin hernia repair will decrease R2 when participating in a structured educational programme. R3 LoE: 2C LoC: strong consensus, 127/133=95% R4 36. Specializing in groin hernia repair promotes standardizing peri-operative care, which R5 reduces morbidity and lowers the recurrence rate. R6 LoE: 2C LoC: consensus, 101/132=77% R7 37. Numbers needed to reach competence in TAPP-repair appear to be lower than for TEP- R8 R9 repair. R10 LoE: 5 LoC: consensus, 89/108=82% R11 Costs R12 38. Total costs of endoscopic groin hernia repair appear to be similar to those of open R13 repair: direct costs are higher while indirect costs are lower. R14 LoE: 1A LoC: majority, 86/117=74% R15 R16 R17 Discussion R18 R19 Consensus, which we defined as agreement among at least 75 percent of participants in R20 the consensus conference, was reached in three-quarters (36/48) of the statements. Five of R21 36 statements with consensus were supported by level 1 evidence while 21 statements with R22 consensus were based on level 5 evidence, illustrating the paucity of high level evidence for R23 R24 endoscopic repair of groin hernias. Interestingly, the degree of consensus for level 1 statements R25 was 63 percent (5/8) and 84 percent (21/25) for level 5 statements. Apparently, high level R26 of evidence statements are not consistently associated with strong consensus of the surgical R27 community and vice versa. R28 R29 The existing guidelines published by the EHS and IEHS both are based on review of the literature by R30 a small group of experts without formal contributions of their members. Several surgical scientists R31 s of the EHS and IEHS were included in the expert panel of the EAES consensus development R32 conference to ensure a platform consisting of representatives from all societies with a special R33 focus on groin hernia surgery. Combining medical evidence with the opinions of both experts and R34 the surgical community provides a unique method to develop best practice guidelines. R35 R36 R37 R38 R39

122 | Chapter 8 A limitation of this study is the involvement of less than 10 percent (of approximately 2700) R1 of the EAES member. To increase involvement, the statements of the consensus development R2 conference were posted on the EAES website four weeks before the meeting in Brussels. In R3 R4 addition, a recording of the consensus development conference was posted on the EAES website R5 after the meeting with a digital voting module to allow members who could not attend the R6 conference to contribute. In spite of the limited number of members that used this opportunity, R7 employment of digital communication methods deserves further attention to reach out to those R8 who can not readily attend conferences in person. R9 R10 In conclusion, more than three-quarters of surgeons involved in the 2012 EAES consensus R11 development conference agreed on three-quarters of 48 statements regarding endoscopic repair R12 of groin hernias. Collaboration between all societies with a focus on groin hernias such as the R13 EAES, EHS and IEHS, high caliber scientific studies on groin hernias and including opinions and R14 experiences of the surgical community at large are the elements to further improve the quality of R15 care for our patients with groin hernias. R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 8 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

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126 | Chapter 8 60. Chui LB, Ng WT, Sze YS, Yuen KS, Wong YT, and Kong CK. Prospective, randomized, controlled trial comparing lightweight versus heavyweight mesh in chronic pain incidence after TEP repair of bilateral R1 inguinal hernia. Surg Endosc. 2010, Nov;24(11):2735-8. R2 61. Chowbey PK, Garg N, Sharma A, Khullar R, Soni V, Baijal M, and Mittal T. Prospective randomized R3 clinical trial comparing lightweight mesh and heavyweight polypropylene mesh in endoscopic totally extraperitoneal groin hernia repair. Surg Endosc. 2010, Dec;24(12):3073-9. R4 62. Bittner R, Leibl BJ, Kraft B, and Schwarz J. One-year results of a prospective, randomised clinical trial R5 comparing four meshes in laparoscopic inguinal hernia repair (TAPP). Hernia. 2011, Oct;15(5):503-10. R6 63. Smith AI, Royston CM, and Sedman PC. Stapled and nonstapled laparoscopic transabdominal R7 preperitoneal (TAPP) inguinal hernia repair. A prospective randomized trial. Surg Endosc. 1999, Aug;13(8):804-6. R8 64. Olmi S, Scaini A, Erba L, Guaglio M, and Croce E. Quantification of pain in laparoscopic transabdominal R9 preperitoneal (TAPP) inguinal hernioplasty identifies marked differences between prosthesis fixation R10 systems. Surgery. 2007, Jul;142(1):40-6. R11 65. Fortelny RH, Petter-Puchner AH, May C, Jaksch W, Benesch T, Khakpour Z, et al. The impact of atraumatic fibrin sealant vs. staple mesh fixation in TAPP hernia repair on chronic pain and quality of R12 life: results of a randomized controlled study. Surg Endosc. 2012, Jan;26(1):249-54. R13 66. Brügger L, Bloesch M, Ipaktchi R, Kurmann A, Candinas D, and Beldi G. Objective hypoesthesia and R14 pain after transabdominal preperitoneal hernioplasty: a prospective, randomized study comparing R15 tissue adhesive versus spiral tacks. Surg Endosc. 2012, Apr;26(4):1079-85. 67. Lovisetto F, Zonta S, Rota E, Mazzilli M, Bardone M, Bottero L, et al. Use of human fibrin glue R16 (Tissucol) versus staples for mesh fixation in laparoscopic transabdominal preperitoneal hernioplasty: a R17 prospective, randomized study. Ann Surg. 2007, Feb;245(2):222-31. R18 68. Boldo E, Armelles A, Perez de Lucia G, Martin F, Aracil JP, Miralles JM, et al. Pain after laparascopic bilateral hernioplasty : Early results of a prospective randomized double-blind study comparing fibrin R19 versus staples. Surg Endosc. 2008, May;22(5):1206-9. R20 69. Tam KW, Liang HH, and Chai CY. Outcomes of staple fixation of mesh versus nonfixation in laparoscopic R21 total extraperitoneal inguinal repair: a meta-analysis of randomized controlled trials. World J Surg. R22 2010, Dec;34(12):3065-74. 70. Teng YJ, Pan SM, Liu YL, Yang KH, Zhang YC, Tian JH, and Han JX. A meta-analysis of randomized R23 controlled trials of fixation versus nonfixation of mesh in laparoscopic total extraperitoneal inguinal R24 hernia repair. Surg Endosc. 2011, Sep;25(9):2849-58. R25 71. Kaul A, Hutfless S, Le H, Hamed SA, Tymitz K, Nguyen H, and Marohn MR. Staple versus fibrin glue R26 fixation in laparoscopic total extraperitoneal repair of inguinal hernia: a systematic review and meta- analysis. Surg Endosc. 2012, May;26(5):1269-78. R27 72. Garg P, Nair S, Shereef M, Thakur JD, Nain N, Menon GR, and Ismail M. Mesh fixation compared to R28 nonfixation in total extraperitoneal inguinal hernia repair: a randomized controlled trial in a rural center R29 in India. Surg Endosc. 2011, Oct;25(10):3300-6. 8 73. Gersin KS, Heniford BT, Garcia-Ruiz A, and Ponsky JL. Missed lipoma of the spermatic cord. A pitfall of R30 transabdominal preperitoneal laparoscopic hernia repair. Surg Endosc. 1999, Jun;13(6):585-7. R31 74. Nasr AO, Tormey S, and Walsh TN. Lipoma of the cord and round ligament: an overlooked diagnosis? R32 Hernia. 2005, Oct;9(3):245-7. R33 75. Lau H, Loong F, Yuen WK, and Patil NG. Management of herniated retroperitoneal adipose tissue during endoscopic extraperitoneal inguinal hernioplasty. Surg Endosc. 2007, Sep;21(9):1612-6. R34 76. Carilli S, Alper A, and Emre A. Inguinal cord lipomas. Hernia. 2004, Aug;8(3):252-4. R35 77. Langeveld HR, van’t Riet M, Weidema WF, Stassen LP, Steyerberg EW, Lange J, et al. Total extraperitoneal R36 inguinal hernia repair compared with Lichtenstein (the LEVEL-Trial): a randomized controlled trial. Ann R37 Surg. 2010, May;251(5):819-24. R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 127 78. Fleming WR, Elliott TB, Jones RM, and Hardy KJ. Randomized clinical trial comparing totally R1 extraperitoneal inguinal hernia repair with the Shouldice technique. Br J Surg. 2001, Sep;88(9):1183-8. R2 79. Schmedt CG, Sauerland S, and Bittner R. Comparison of endoscopic procedures vs Lichtenstein and R3 other open mesh techniques for inguinal hernia repair: a meta-analysis of randomized controlled trials. Surg Endosc. 2005, Feb;19(2):188-99. R4 80. Bittner R, Sauerland S, and Schmedt CG. Comparison of endoscopic techniques vs Shouldice and other R5 open nonmesh techniques for inguinal hernia repair: a meta-analysis of randomized controlled trials. R6 Surg Endosc. 2005, May;19(5):605-15. R7 81. Eklund A, Rudberg C, Smedberg S, Enander LK, Leijonmarck CE, Osterberg J, and Montgomery A. Short-term results of a randomized clinical trial comparing Lichtenstein open repair with totally R8 extraperitoneal laparoscopic inguinal hernia repair. Br J Surg. 2006, Sep;93(9):1060-8. R9 82. Eklund A, Rudberg C, Leijonmarck CE, Rasmussen I, Spangen L, Wickbom G, et al. Recurrent inguinal R10 hernia: randomized multicenter trial comparing laparoscopic and Lichtenstein repair. Surg Endosc. R11 2007, Apr;21(4):634-40. 83. Pokorny H, Klingler A, Schmid T, Fortelny R, Hollinsky C, Kawji R, et al. Recurrence and complications R12 after laparoscopic versus open inguinal hernia repair: results of a prospective randomized multicenter R13 trial. Hernia. 2008, Aug;12(4):385-9. R14 84. Wake BL, McCormack K, Fraser C, Vale L, Perez J, and Grant AM. Transabdominal pre-peritoneal (TAPP) R15 vs totally extraperitoneal (TEP) laparoscopic techniques for inguinal hernia repair. Cochrane Database Syst Rev. 2005;(1):CD004703. R16 85. Bektaş H, Bilsel Y, Ersöz F, Sarı S, Mutlu T, Arıkan S, and Kaygusuz A. Comparison of totally R17 extraperitoneal technique and darn plication of primary inguinal hernia. J Laparoendosc Adv Surg Tech R18 A. 2011, Sep;21(7):583-8. 86. Kumar S, Nixon SJ, and MacIntyre IM. Laparoscopic or Lichtenstein repair for recurrent inguinal hernia: R19 one unit’s experience. J R Coll Surg Edinb. 1999, Oct;44(5):301-2. R20 87. Dedemadi G, Sgourakis G, Karaliotas C, Christofides T, Kouraklis G, and Karaliotas C. Comparison R21 of laparoscopic and open tension-free repair of recurrent inguinal hernias: a prospective randomized R22 study. Surg Endosc. 2006, Jul;20(7):1099-104. 88. Felix E, Scott S, Crafton B, Geis P, Duncan T, Sewell R, and McKernan B. Causes of recurrence after R23 laparoscopic hernioplasty. A multicenter study. Surg Endosc. 1998, Mar;12(3):226-31. R24 89. Tamme C, Scheidbach H, Hampe C, Schneider C, and Köckerling F. Totally extraperitoneal endoscopic R25 inguinal hernia repair (TEP). Surg Endosc. 2003, Feb;17(2):190-5. R26 90. Leibl BJ, Jäger C, Kraft B, Kraft K, Schwarz J, Ulrich M, and Bittner R. Laparoscopic hernia repair--TAPP or/and TEP? Langenbecks Arch Surg. 2005, Apr;390(2):77-82. R27 91. Liem MS, Halsema JA, van der Graaf Y, Schrijvers AJ, and van Vroonhoven TJ. Cost-effectiveness R28 of extraperitoneal laparoscopic inguinal hernia repair: a randomized comparison with conventional R29 herniorrhaphy. Coala trial group. Ann Surg. 1997, Dec;226(6):668-75; discussion 675-6. R30 92. Köninger J, Redecke J, and Butters M. Chronic pain after hernia repair: a randomized trial comparing Shouldice, Lichtenstein and TAPP. Langenbecks Arch Surg. 2004, Oct;389(5):361-5. R31 93. Singh AN, Bansal VK, Misra MC, Kumar S, Rajeshwari S, Kumar A, et al. Testicular functions, chronic R32 groin pain, and quality of life after laparoscopic and open mesh repair of inguinal hernia: a prospective R33 randomized controlled trial. Surg Endosc. 2012, May;26(5):1304-17. R34 94. Gholghesaei M, Langeveld HR, Veldkamp R, and Bonjer HJ. Costs and quality of life after endoscopic repair of inguinal hernia vs open tension-free repair: a review. Surg Endosc. 2005, Jun;19(6):816-21. R35 95. Hallén M, Westerdahl J, Nordin P, Gunnarsson U, and Sandblom G. Mesh hernia repair and male R36 infertility: a retrospective register study. Surgery. 2012, Jan;151(1):94-8. R37 96. Robertson GS, Burton PR, and Haynes IG. How long do patients convalescence after inguinal R38 herniorrhaphy? Current principles and practice. Ann R Coll Surg Engl. 1993, Jan;75(1):30-3. R39

128 | Chapter 8 97. Shulman AG, Amid PK, and Lichtenstein IL. Returning to work after herniorrhaphy. BMJ. 1994, Jul 23;309(6949):216-7. R1 98. Ross AP. Incidence of inguinal hernia recurrence. Effect of time off work after repair. Ann R Coll Surg R2 Engl. 1975, Dec;57(6):326-8. R3 99. Bourke JB, Lear PA, and Taylor M. Effect of early return to work after elective repair of inguinal hernia: R4 Clinical and financial consequences at one year and three years. Lancet. 1981, Sep 19;2(8247):623-5. R5 100. Taylor EW, and Dewar EP. Early return to work after repair of a unilateral inguinal hernia. Br J Surg. 1983, Oct;70(10):599-600. R6 101. Callesen T, Klarskov B, Bech K, and Kehlet H. Short convalescence after inguinal herniorrhaphy with R7 standardised recommendations: duration and reasons for delayed return to work. Eur J Surg. 1999, R8 Mar;165(3):236-41. R9 102. Bay-Nielsen M, Thomsen H, Andersen FH, Bendix JH, Sørensen OK, Skovgaard N, and Kehlet H. Convalescence after inguinal herniorrhaphy. Br J Surg. 2004, Mar;91(3):362-7. R10 103. Welsh CL, and Hopton D. Advice about driving after herniorrhaphy. Br Med J. 1980, May R11 3;280(6223):1134-5. R12 104. Wilson MS, Irving SO, Iddon J, Deans GT, and Brough WA. A measurement of the ability to drive after R13 different types of inguinal hernia repair. Surg Laparosc Endosc. 1998, Oct;8(5):384-7. 105. Kald A, and Nilsson E. Quality assessment in hernia surgery. Qual Assur Health Care. 1991;3(3):205-10. R14 106. Haapaniemi S, and Nilsson E. Recurrence and pain three years after groin hernia repair. Validation R15 of postal questionnaire and selective physical examination as a method of follow-up. Eur J Surg. R16 2002;168(1):22-8. R17 107. López-Cano M, Vilallonga R, Sánchez JL, Hermosilla E, and Armengol M. Short postal questionnaire and selective clinical examination combined with repeat mailing and telephone reminders as a method R18 of follow-up in hernia surgery. Hernia. 2007, Oct;11(5):397-402. R19 108. Brazier JE, Harper R, Jones NM, O’Cathain A, Thomas KJ, Usherwood T, and Westlake L. Validating R20 the SF-36 health survey questionnaire: new outcome measure for primary care. BMJ. 1992, Jul R21 18;305(6846):160-4. 109. Heniford BT, Walters AL, Lincourt AE, Novitsky YW, Hope WW, and Kercher KW. Comparison of generic R22 versus specific quality-of-life scales for mesh hernia repairs. J Am Coll Surg. 2008, Apr;206(4):638-44. R23 110. Muysoms F, Campanelli G, Champault GG, DeBeaux AC, Dietz UA, Jeekel J, et al. EuraHS: the R24 development of an international online platform for registration and outcome measurement of ventral abdominal wall hernia repair. Hernia. 2012, Jun;16(3):239-50. R25 111. Loos MJ, Houterman S, Scheltinga MR, and Roumen RM. Evaluating postherniorrhaphy groin pain: R26 Visual Analogue or Verbal Rating Scale? Hernia. 2008, Apr;12(2):147-51. R27 112. Fränneby U, Gunnarsson U, Andersson M, Heuman R, Nordin P, Nyrén O, and Sandblom G. Validation R28 of an Inguinal Pain Questionnaire for assessment of chronic pain after groin hernia repair. Br J Surg. R29 2008, Apr;95(4):488-93. 8 113. Lamb AD, Robson AJ, and Nixon SJ. Recurrence after totally extraperitoneal laparoscopic repair: R30 implications for operative technique and surgical training. Surgeon. 2006, Oct;4(5):299-307. R31 114. Lovisetto F, Zonta S, Rota E, Bottero L, Faillace G, Turra G, et al. Laparoscopic transabdominal preperitoneal R32 (TAPP) hernia repair: surgical phases and complications. Surg Endosc. 2007, Apr;21(4):646-52. R33 115. Choi YY, Kim Z, and Hur KY. Learning curve for laparoscopic totally extraperitoneal repair of inguinal hernia. Can J Surg. 2012, Feb;55(1):33-6. R34 116. Liem MS, van Steensel CJ, Boelhouwer RU, Weidema WF, Clevers GJ, Meijer WS, et al. The learning R35 curve for totally extraperitoneal laparoscopic inguinal hernia repair. Am J Surg. 1996, Feb;171(2):281- R36 5. R37 117. Feliu-Palà X, Martín-Gómez M, Morales-Conde S, and Fernández-Sallent E. The impact of the surgeon’s experience on the results of laparoscopic hernia repair. Surg Endosc. 2001, Dec;15(12):1467-70. R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 129 118. Deysine M. Hernia clinic in a teaching institution: creation and development. Hernia. 2001, Jun;5(2):65- R1 9. R2 119. Zendejas B, Cook DA, Bingener J, Huebner M, Dunn WF, Sarr MG, and Farley DR. Simulation-based R3 mastery learning improves patient outcomes in laparoscopic inguinal hernia repair: a randomized controlled trial. Ann Surg. 2011, Sep;254(3):502-9; discussion 509-11. R4 120. Kingsnorth AN, Bowley DM, and Porter C. A prospective study of 1000 hernias: results of the Plymouth R5 Hernia Service. Ann R Coll Surg Engl. 2003, Jan;85(1):18-22. R6 121. Heikkinen T, Haukipuro K, Leppälä J, and Hulkko A. Total costs of laparoscopic and lichtenstein inguinal R7 hernia repairs: a randomized prospective study. Surg Laparosc Endosc. 1997, Feb;7(1):1-5. R8 122. Wellwood J, Sculpher MJ, Stoker D, Nicholls GJ, Geddes C, Whitehead A, et al. Randomised controlled trial of laparoscopic versus open mesh repair for inguinal hernia: outcome and cost. BMJ. 1998, Jul R9 11;317(7151):103-10. R10 123. Tanphiphat C, Tanprayoon T, Sangsubhan C, and Chatamra K. Laparoscopic vs open inguinal hernia R11 repair. A randomized, controlled trial. Surg Endosc. 1998, Jun;12(6):846-51. R12 124. Paganini AM, Lezoche E, Carle F, Carlei F, Favretti F, Feliciotti F, et al. A randomized, controlled, clinical study of laparoscopic vs open tension-free inguinal hernia repair. Surg Endosc. 1998, Jul;12(7):979-86. R13 125. Heikkinen TJ, Haukipuro K, Koivukangas P, and Hulkko A. A prospective randomized outcome and cost R14 comparison of totally extraperitoneal endoscopic hernioplasty versus Lichtenstein hernia operation R15 among employed patients. Surg Laparosc Endosc. 1998, Oct;8(5):338-44. R16 126. Medical Research Council Laparoscopic Groin Hernia Trial Group. Cost-utility analysis of open versus laparoscopic groin hernia repair: results from a multicentre randomized clinical trial. Br J Surg. 2001, R17 May;88(5):653-61. R18 127. Papachristou EA, Mitselou MF, and Finokaliotis ND. Surgical outcome and hospital cost analyses of R19 laparoscopic and open tension-free hernia repair. Hernia. 2002, Jul;6(2):68-72. R20 128. Schneider BE, Castillo JM, Villegas L, Scott DJ, and Jones DB. Laparoscopic totally extraperitoneal versus Lichtenstein herniorrhaphy: cost comparison at teaching hospitals. Surg Laparosc Endosc Percutan R21 Tech. 2003, Aug;13(4):261-7. R22 129. Khajanchee YS, Kenyon TA, Hansen PD, and Swanström LL. Economic evaluation of laparoscopic and R23 open inguinal herniorrhaphies: the effect of cost-containment measures and internal hospital policy decisions on costs and charges. Hernia. 2004, Aug;8(3):196-202. R24 130. Anadol ZA, Ersoy E, Taneri F, and Tekin E. Outcome and cost comparison of laparoscopic transabdominal R25 preperitoneal hernia repair versus Open Lichtenstein technique. J Laparoendosc Adv Surg Tech A. R26 2004, Jun;14(3):159-63. R27 131. Hynes DM, Stroupe KT, Luo P, Giobbie-Hurder A, Reda D, Kraft M, et al. Cost effectiveness of laparoscopic versus open mesh hernia operation: results of a Department of Veterans Affairs randomized clinical R28 trial. J Am Coll Surg. 2006, Oct;203(4):447-57. R29 132. Jacobs VR, and Morrison JE. Comparison of institutional costs for laparoscopic preperitoneal inguinal R30 hernia versus open repair and its reimbursement in an ambulatory surgery center. Surg Laparosc Endosc Percutan Tech. 2008, Feb;18(1):70-4. R31 133. Butler RE, Burke R, Schneider JJ, Brar H, and Lucha PA. The economic impact of laparoscopic R32 inguinal hernia repair: results of a double-blinded, prospective, randomized trial. Surg Endosc. 2007, R33 Mar;21(3):387-90. R34 134. Stylopoulos N, Gazelle GS, and Rattner DW. A cost--utility analysis of treatment options for inguinal hernia in 1,513,008 adult patients. Surg Endosc. 2003, Feb;17(2):180-9. R35 135. Vale L, Ludbrook A, and Grant A. Assessing the costs and consequences of laparoscopic vs. open R36 methods of groin hernia repair: a systematic review. Surg Endosc. 2003, Jun;17(6):844-9. R37 136. Vale L, Grant A, McCormack K, Scott NW, and EU Hernia Trialists Collaboration. Cost-effectiveness R38 of alternative methods of surgical repair of inguinal hernia. Int J Technol Assess Health Care. 2004;20(2):192-200. R39

130 | Chapter 8 137. McCormack K, Wake BL, Fraser C, Vale L, Perez J, and Grant A. Transabdominal pre-peritoneal (TAPP) versus totally extraperitoneal (TEP) laparoscopic techniques for inguinal hernia repair: a systematic R1 review. Hernia. 2005, May;9(2):109-14. R2 138. Kuhry E, van Veen RN, Langeveld HR, Steyerberg EW, Jeekel J, and Bonjer HJ. Open or endoscopic total R3 extraperitoneal inguinal hernia repair? A systematic review. Surg Endosc. 2007, Feb;21(2):161-6. R4 139. Vale L, Grant A, McCormack K, Scott NW, and EU Hernia Trialists Collaboration. Cost-effectiveness of alternative methods of surgical repair of inguinal hernia. Int J Technol Assess Health Care. R5 2004;20(2):192-200. R6 140. McCormack K, Wake BL, Fraser C, Vale L, Perez J, and Grant A. Transabdominal pre-peritoneal (TAPP) R7 versus totally extraperitoneal (TEP) laparoscopic techniques for inguinal hernia repair: a systematic review. Hernia. 2005, May;9(2):109-14. R8 141. Kuhry E, van Veen RN, Langeveld HR, Steyerberg EW, Jeekel J, and Bonjer HJ. Open or endoscopic total R9 extraperitoneal inguinal hernia repair? A systematic review. Surg Endosc. 2007, Feb;21(2):161-6. R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 8 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

EAES Consensus Development Conference on endoscopic repair of groin hernias | 131

Chapter 9

Summary and Discussion R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

134 | Chapter 9 Summary R1 R2

The research described in this thesis started with a retrospective analysis of 101 patients whose R3 R4 hernia was repaired with the use of an onlay mesh technique (chapter 2). Wound infection was R5 reported in 21% of the patients, seroma was reported in 27% of the patients. Recurrence was R6 found in 16% of the patients who were seen at follow-up (n=71). This modified onlay mesh R7 technique seems to be an acceptable and easy technique for large and/or more complicated R8 incisional hernias, especially since it is not necessary to enter the abdominal cavity. The outcomes R9 do not differ from the results of other accepted open techniques such as the component R10 separation technique. R11 R12 Health related quality of life (HRQL) was examined in the patient group that had their incisional R13 hernia repaired by a large onlay mesh (chapter 3). The Short Form 36 and the Karnofsky R14 performance status scale were used as tools to measure quality of life. A matched population R15 was obtained from the Netherlands Cancer Institute to perform a matched control analysis. No R16 difference in HRQL could be found. Onlay incisional hernia repair therefore does not seem to R17 affect HRQL. R18 R19 R20 While retrospectively studying patients treated for large incisional hernias, several patients who R21 were treated with an open abdomen were identified. Literature about this topic is limited and the R22 number of patients treated with an open abdomen is low, it is therefore impossible to perform R23 a randomized controlled trial or conduct a meta-analysis. A retrospective analysis to study this R24 group of patients was started (chapter 4). The manuscript aims to analyze patients who were R25 treated with an open abdomen in a university hospital and a large teaching hospital and to study R26 the existing literature concerning open abdomen treatment. There is no evidence to advocate R27 a certain treatment strategy. Temporary fascial closure with the aim to achieve a delayed fascial R28 closure is a demanding and expensive treatment. Anticipating on a planned ventral hernia is an R29 easier to perform and less demanding technique for severely ill patients, and might therefore be R30 the best treatment strategy there is so far. The hernia can be repaired or treated conservatively R31 after the patient recovered. R32 9 R33 R34 In current surgical practice, there is ongoing discussion about the possible benefits and R35 disadvantages of laparoscopic incisional hernia surgery. Scientific evidence is lacking to determine R36 whether laparoscopic correction is superior to conventional open techniques. This study will R37 provide evidence on the effectiveness of laparoscopic incisional hernia repair as compared R38 R39

Summary and Discussion | 135 R1 to open repair. Also, there is a need to know the natural course of a conservatively treated R2 incisional hernia. Registration of all patients with an incisional hernia could therefore be valuable. R3 Furthermore, we want to know what type of incisional hernia is treated with what type of surgical R4 repair, to find out if subgroups could be created with an individual treatment advice. A large R5 randomized controlled trial comparing the efficacy of open and laparoscopic incisional hernia R6 repair was initiated. Patients who do not participate in the INCH trial will be registered in a R7 database. This study is called ‘INCH trial’ (chapter 5). Guidelines about whether a patient can R8 R9 be treated with the use of laparoscopy are non-existent. The INCH study group decided to leave R10 the decision at the discretion of the surgeon. The participating surgeons are hernia experts and R11 performed at least fifty laparoscopic incisional hernia repairs each. R12 R13 To be able to measure disease specific quality of life in the INCH trial, authors validated the Carolina R14 Comfort Scale (CCS) in Dutch (chapter 6). The CCS is a questionnaire designed specifically to R15 measure quality of life in patients undergoing mesh hernia repair. It was developed and validated R16 in English by Heniford et al (ref). The questionnaire was translated into Dutch and tested on a R17 hundred patients undergoing mesh hernia repair within one week after surgery. Patients were R18 asked to complete the short Form 36 and to repeat the CCS three weeks after surgery. The R19 Dutch CCS appears a valid and clinically relevant tool for assessing quality of life after repair of R20 abdominal wall hernia with mesh. It will therefore be used in the INCH trial. R21 R22 Recommendations or standardization of the open technique that can be used in the INCH trial is R23 R24 hard to give, as there is not enough evidence to support a certain open procedure. Onlay, sublay R25 and component separation technique appear to be equally effective. Laparoscopic repair has not R26 been standardized either. R27 A review of the literature was performed to evaluate the surgical technique of laparoscopic R28 incisional hernia repair with outcomes, to define the optimal technique (chapter 7). The use of R29 transfascial sutures, the amount of overlap of the mesh of the fascia and the type of mesh used R30 were analyzed. No specific parameter could be identified to influence the recurrence rate. R31 The use of a mesh with sufficient overlap (preferably >5cm in each direction) of the mesh of the R32 fascia was the only mandatory factor in the INCH trial in each chosen technique, as in general, R33 this is thought to reduce the recurrence rate. R34 R35 While starting the INCH trial, the EAES consensus development conference 2012 on endoscopic R36 groin hernia repair was organized. With the use of available medical evidence combined with R37 the opinions of an expert panel and the membership of the EAES, practical guidelines on how to R38 R39

136 | Chapter 9 handle a groin hernia could be formulated (chapter 8). A consensus development conference can R1 be a very valuable tool especially in topics where evidence based medicine is lacking. R2 R3 R4 R5 Conclusions R6 R7 The following conclusions may be drawn from the studies in this thesis. R8 - The onlay technique for the repair of (large) incisional hernias is an acceptable method R9 (chapter 2). R10 - Onlay incisional hernia repair does not seem to (negatively) affect the health related R11 quality of life (chapter 3). R12 - The best treatment modality for patients treated with an open abdomen is yet to be R13 found (chapter 4). Absorbable mesh closure, i.e. Vicryl, is a good option in severely ill R14 patients where delayed fascial closure it not the main concern. R15 - The Dutch Carolina Comfort Scale is a reliable instrument to measure quality of life in R16 patients treated with mesh hernia repair in the Dutch-speaking population (chapter 6). R17 - No recommendations can be drawn from a systematic review of over 2000 patients R18 R19 concerning the influence of surgical technique of laparoscopic incisional hernia repair R20 on recurrence rate (chapter 7). R21 - A consensus development conference can be a very valuable tool especially in topics R22 where evidence based medicine is lacking (chapter 8) R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 9 R33 R34 R35 R36 R37 R38 R39

Summary and Discussion | 137 R1 Discussion R2

R3 Reconstruction of the abdominal wall is complex given the multiple functions of the abdominal wall R4 and its intricate anatomy. Available surgical methods to restore the abdominal wall are limited to R5 sheets of synthetic material, which are a pale shadow of the multilayer flexible architecture of the R6 abdominal wall. Hence, it is not surprising that the outcomes of current incisional hernia surgery R7 are mediocre. Due to impaired healing of laparotomies in more than 15 % of patients, incisional R8 R9 hernias are a frequent disorder affecting the quality of life of many patients. Close evaluation of R10 the outcomes of various employed techniques is mandatory to identify the technique with the R11 best ratio between outcomes and morbidity. R12 R13 Research on abdominal wall hernia repair gravitates to the management of groin hernia. The aim R14 of research in inguinal hernia repair has shifted from prevention of recurrences to minimizing R15 chronic post-operative pain and the effects on other quality of life parameters. Research on R16 incisional hernia repair still focuses on decreasing post-operative morbidity and reduction of R17 the recurrence rate. More research needs to be done in order to optimize the surgical care of R18 patients suffering from an incisional hernia. Morbidity and recurrence rate is unacceptably high R19 at 15-20%. The introduction of laparoscopic incisional hernia repair might improve outcomes R20 such as wound-infections and hospitalization in patients with hernias suitable for laparoscopic R21 surgery. Nonetheless, it is unknown if the functional outcome or quality of life improves with the R22 application of the laparoscopic repair. Also, there will still be patients with incisional hernias that R23 R24 cannot be repaired by the use of the laparoscopic repair, such as patients with large complicated R25 abdominal wall defects. R26 R27 General surgeons have performed surgery for abdominal wall hernias for centuries. Incisional R28 hernias can be repaired using open or laparoscopic techniques. The indication for repair, as well as R29 the choice for the open or the laparoscopic approach is unclear. Surgeons choose their technique R30 based on their previous experience, characteristics of the abdominal wall hernia, patient history, R31 available equipment and prosthesis. This choice is far from evidence based. It is only possible to R32 find the best treatment option for different kind of patients with abdominal wall hernias through R33 doing more research. R34 The interaction between mesh, its fixation and the physical properties of the abdominal wall R35 constitute as system, which is referred to by Bittner et al as the ‘mesh-fixation-abdominal wall R36 system (1). These three elements need to be evaluated interdependently to determine the optimal R37 treatment strategy. Evaluating one of these in isolation will not reveal clinically relevant results as R38 R39 shown in chapter 7.

138 | Chapter 9 In general, surgeons assume that an overlap of the mesh of the defect needs to be at least 5cm. R1 The mesh usually shrinks after implantation in the abdominal wall and therefore a wide overlap is R2 needed. Nevertheless, when the hernia is at the periphery of the abdominal wall, it is sometimes R3 R4 impossible to reach 5cm of overlap because of the proximity of the skeletal structures. R5 Fixation of the mesh to the abdominal wall in open hernia repair is usually not an issue because R6 the mesh is held in position between the different layers of the abdominal wall in the sublay R7 technique. In laparoscopic repair tackers and/or transfascial sutures fixate the mesh to the R8 abdominal wall. The fixation should suffice preventing (early) recurrences, while too many tackers R9 or sutures can increase post-operative pain. R10 R11 The employment of a prosthetic mesh during incisional hernia repair either open or laparoscopic R12 techniques, is known to lower the recurrence rate (2). Prosthetic meshes are available in many R13 different shapes and sizes. Although much emphasis is put on the use of prosthesis, the use R14 of mesh is not the main reason for an effective hernia repair. It is all about the “mesh-fixation- R15 abdominal wall” system. Properties of the mesh (porosity, elasticity, and the architecture of the R16 weave) do influence this system, but the individual patient characteristics probably contribute R17 equally. Body Mass Index, age and gender influence the anterior abdominal wall movements. R18 R19 Also, histological features, like collagen structure of the individual abdominal wall vary. Because of R20 these individual variances, forces acting on the prosthesis used to repair the abdominal wall differ. R21 The material used for abdominal wall reinforcement should therefore be more individualized. R22 Tailor-made meshes based on the individual body shape, fascial structure and anterior abdominal R23 wall imaging (by a 3D printer) are the future. However, the exact methods to enable the creation R24 of a tailor-made mesh are unclear. R25 R26 Several (open) surgical techniques are available for the repair of large incisional hernias with loss R27 of domain. The open component separation technique is a frequently used surgical technique R28 for these large hernias. The muscular layers of the abdominal wall are dissected to enlarge R29 the muscular abdominal wall surface. The tissue damage is substantial and the vascularization R30 might get compromised, which probably affects the abdominal wall function post-operatively. R31 Laparoscopic component separation technique seems to be feasible, probably reduces wound- R32 R33 healing problems and might therefore improve functional outcome. 9 R34 R35 The modified onlay technique described in chapter 2 and 3 does not require separation of the R36 muscular layers. It does involve separation of the subcutaneous tissue from the fascia. Therefore, R37 clinical relevant seromas occur more frequently. The advantage of this procedure is that it is a R38 R39

Summary and Discussion | 139 R1 fast and simple technique and it does not require entering the abdominal cavity. Recurrence rates R2 after this onlay repair are comparable to other open techniques. The technique does not seem R3 to (negatively) affect the quality of life for these patients. Abdominal wall function has not been R4 examined; patients do report to feel the mesh in certain movements after this modified onlay R5 incisional hernia repair. R6 Hybrid techniques, combining open and laparoscopic techniques, gain popularity in the repair of R7 large incisional hernias. Intra-abdominal adhesions can be reduced and the fascial edges can be R8 R9 brought together with the use of the open approach, while the mesh can be positioned and fixed R10 to the abdominal wall using the laparoscopic approach. R11 R12 The surgical techniques that are used to repair an abdominal wall hernia need to be more uniform. R13 Standardizing surgical techniques is a necessary method to improve the quality of care that we R14 provide to patients with incisional hernias. There is no gold standard for incisional hernia repair R15 and the accepted available techniques used by general surgeons differ from one to another. The R16 term ‘incisional hernia’ is probably too general. Specific types of incisional hernias and patients R17 with such a hernia should be distinguished in order to be able to make a tailor made treatment R18 strategy for each subgroup. R19 R20 Surgical residents should be trained in abdominal wall hernia repair. A structured laparoscopic R21 training program in hernia repair improves surgeons’ proficiency in the operating room. The R22 learning curve for incisional hernia repair is unclear. Outcomes are thought to improve by surgeon R23 R24 volume. Therefore, experienced hernia surgeons should perform complex abdominal wall hernia R25 repairs. R26 R27 The International Endohernia Society recently published the fist guidelines for laparoscopic R28 incisional hernia repair (1,3,4). These guidelines help us to clarify some topics, but many questions R29 remain unanswered. Thorough registries of patients with incisional hernias who undergo surgical R30 repair and of those who abstain from surgery, such as the EuraHS and HerniaMed, are of great R31 importance to learn more about the outcomes of surgical and non-surgical management of R32 incisional hernias. These databases might help surgeons to choose the proper material and R33 technique to repair a hernia. Randomized trials are needed to know what type of incisional hernia R34 is suitable for what surgical technique and the effect on morbidity such as recurrence rate and R35 quality of life. The INCH trial, a randomized controlled trial and registry that started July 2012, R36 aims to find answers to these questions. R37 R38 R39

140 | Chapter 9 References R1 R2 1. Bittner R, Bingener-Casey J, Dietz U, Fabian M, Ferzli G, Fortelny R, et al. Guidelines for laparoscopic R3 treatment of ventral and incisional abdominal wall hernias (international endohernia society [IEHS])- part III. Surg Endosc 2014, Feb;28(2):380-404. R4 2. Luijendijk RW, Hop WC, van den Tol MP, de Lange DC, Braaksma MM, IJzermans JN, et al. A comparison R5 of suture repair with mesh repair for incisional hernia. N Engl J Med 2000, Aug 10;343(6):392-8. R6 3. Bittner R, Bingener-Casey J, Dietz U, Fabian M, Ferzli GS, Fortelny RH, et al. Guidelines for laparoscopic R7 treatment of ventral and incisional abdominal wall hernias (international endohernia society [IEHS])— part 2. Surg Endosc 2014, Feb;28(2):353-79. R8 4. Bittner R, Bingener-Casey J, Dietz U, Fabian M, Ferzli GS, Fortelny RH, et al. Guidelines for laparoscopic R9 treatment of ventral and incisional abdominal wall hernias (international endohernia society (IEHS)-part R10 1. Surg Endosc 2014, Jan;28(1):2-29. R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 9 R33 R34 R35 R36 R37 R38 R39

Summary and Discussion | 141

Chapter 10

Nederlandse samenvatting

Dankwoord

Curriculum Vitae R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

144 | Chapter 10 Nederlandse samenvatting R1 R2

Een littekenbreuk is een defect (ook genaamd hernia of breuk) in de bindweefsellaag (fascie) R3 R4 van de buikwand dat ontstaat na een buikoperatie. De huid en het onderhuidse vetweefsel zijn R5 meestal intact, waardoor de inhoud van de buik beschermd is. De opening in de fascie wordt R6 de breukpoort genoemd. Door deze breuk kan er een zwelling in de buikwand ontstaan, die R7 veroorzaakt wordt door het uitpuilen van de inhoud van de buik. Deze zwelling is met name R8 zichtbaar en voelbaar wanneer patiënten staan of hoesten. R9 Een littekenbreuk komt voor bij 10-15% van de patiënten na een buikoperatie en is vaak R10 asymptomatisch, maar kan zorgen voor pijn of ongemak. Daarnaast kunnen mensen het lelijk R11 vinden. Het beklemd raken (‘stranguleren’) van een deel van de (dunne) darm in de breukpoort R12 is de meest gevreesde complicatie. Het is onbekend wat het precieze verloop is van een patiënt R13 met een littekenbreuk die niet wordt behandeld. R14 Een littekenbreuk beïnvloedt de kwaliteit van leven. Littekenbreuken komen vaker voor bij obese R15 patiënten en nadat er een postoperatieve wondinfectie is geweest. Waarschijnlijk spelen nog R16 onbekende afwijkingen in de opbouw van bindweefsel een rol in het ontstaan van een hernia in R17 de buikwand. R18 R19 R20 Een littekenbreuk kan door middel van een standaard open operatie worden verholpen. Daarbij R21 wordt het eerdere litteken gebruikt, wordt het gat in de fascie vaak gesloten met hechtingen en R22 de buikwand verstevigd met een kunststof matje. Deze operatie kan op verschillende manieren R23 uitgevoerd worden, waarbij met name de positie van de mat in de buikwand verschilt. Dit wordt R24 aangeduid door de termen ‘onlay’ en ‘sublay’. R25 Naast de standaard open methode, kan de littekenbreuk ook met een kijkoperatie worden R26 verholpen. We noemen dat ‘laparoscopisch’. Van binnen uit wordt dan de opening in de fascie R27 opgezocht, verklevingen worden los gemaakt en er wordt een kunststof matje over de hernia R28 geplaatst. R29 R30 In dit proefschrift, getiteld ‘buikwandbreuken, verbetering van chirurgische zorg’, is een aantal R31 onderzoeken beschreven. Het onderzoek is gestart met een retrospectieve analyse van 101 R32 patiënten wiens littekenbreuk gecorrigeerd was door middel van de (open) gemodificeerde onlay R33 R34 mesh techniek (hoofdstuk 2). Doel was de uitkomsten na te gaan en die te vergelijken met R35 andere open technieken. Wondinfecties na deze operatie werden gerapporteerd in 21% van de R36 patiënten, klinisch significante seromen kwamen voor bij 27% van de patiënten. Bij 16% van R37 de patiënten werd in de follow-up een recidief vastgesteld (n=71). Deze gemodificeerde onlay 10 R38 mesh techniek lijkt een acceptabele methode om grote en/of gecompliceerde littekenbreuken te R39

Nederlandse samenvatting | 145 R1 corrigeren, met name omdat het niet nodig is de buikholte in te gaan. De uitkomsten verschillen R2 niet van andere geaccepteerde open methoden, zoals de component separation technique, die R3 eveneens worden gebruikt om met name grote littekenbreuken te corrigeren. R4 R5 In de patiëntengroep bij wie hun littekenbreuk gecorrigeerd was met behulp van de gemodificeerde R6 onlay mesh techniek, werd de ziekte-gerelateerde kwaliteit van leven onderzocht (hoofdstuk 3). R7 De Short Form 36 en de Karnofsky Performance Status Scale zijn gebruikt om de kwaliteit van R8 R9 leven te meten. Er werd een gematchte populatie verkregen via het Nederlands Kanker Instituut R10 (NKI) om zo het verschil tussen deze groepen te kunnen bekijken. Er werd geen verschil gevonden R11 in de ziekte gerelateerde kwaliteit van leven. De gemodificeerde onlay mesh techniek lijkt daarom R12 de ziekte gerelateerde kwaliteit van leven niet te beïnvloeden. R13 R14 Tijdens het retrospectief analyseren van patiënten met een littekenbreuk werden verscheidene R15 patiënten met een open buik behandeling geïdentificeerd. Een open buik behandeling betekent R16 dat de buikwand open blijft en de buikinhoud zichtbaar is. Deze behandeling wordt het liefst R17 vermeden, maar soms is er niets anders mogelijk, omdat bijvoorbeeld door een verhoogde druk R18 in de buik de buikwand niet meer gesloten kan worden. Het gaat meestal om zeer ernstig zieke R19 patiënten, die vaak op de intensive care opgenomen liggen. De buikwand van mensen met een R20 open buik moet op een bepaalde manier bij elkaar gehouden worden. Het is onduidelijk wat R21 de beste manier is om dat te doen. Daarnaast is het de vraag of de tijdelijke bedekking een R22 uitgesteld sluiten van de buik moet faciliteren. R23 R24 Er is weinig literatuur over deze patiënten en de aantallen patiënten die behandeld worden met R25 een open buik zijn te laag om naar deze patiënten een gerandomiseerde studie te verrichten. R26 Derhalve werd er en retrospectieve analyse verricht naar deze patiëntengroep (hoofdstuk 4). Deze R27 studie heeft als doel om de patiënten te analyseren die in een groot perifeer opleidingsziekenhuis R28 (het Medisch Centrum Alkmaar) en een academisch ziekenhuis (het VU Medisch Centrum) R29 een open buik behandeling ondergingen. De bestaande literatuur betreffende de open buik R30 behandeling werd daarnaast bestudeerd. R31 Er bestaat geen bewijs welke behandelingsmodaliteit het beste is voor deze patiënten. Over het R32 algemeen zijn er twee scholen: zij die in dezelfde opname de buikwand gesloten willen krijgen en R33 zij die dat niet als doel hebben. Het tijdelijk sluiten van de fascie met een vacuüm systeem, heeft R34 als doel om de buikwand uitgesteld dicht te krijgen. Dit is een dure methode die belastend is voor R35 de patiënt. Anticiperen op een geplande grote littekenbreuk, en het dus open laten van de fascie, R36 is veel minder belastend voor deze patiënten. Daarom lijkt deze behandeling ons tot dusver R37 de beste keuze. Wanneer de patiënt is hersteld kan de littekenbreuk desgewenst gecorrigeerd R38 R39 worden.

146 | Chapter 10 In de huidige chirurgische praktijk is er blijvende discussie over de voor- en nadelen van de R1 laparoscopische littekenbreukcorrectie ten opzichte van de open littekenbreukcorrectie. Er is R2 onvoldoende bewijs om te stellen dat de laparoscopische techniek beter is dan de open techniek. R3 R4 Daarnaast is het nuttig om te weten wat het natuurlijk beloop van een conservatief behandelde R5 littekenbreuk is, iets dat in de literatuur niet of nauwelijks beschreven wordt. Registratie van R6 patiënten met een littekenbreuk is daarom waardevol. Daarnaast willen we graag weten welk R7 type littekenbreuk behandeld wordt met welk type chirurgische correctie. Zo kunnen we kijken R8 of er subgroepen gemaakt kunnen worden en of per subgroep een behandel advies gegeven kan R9 worden. R10 Er werd daarom een studie opgezet met als doel bewijs te leveren over de (kosten-)effectiviteit R11 van de laparoscopische littekenbreukcorrectie vergeleken met de open littekenbreukcorrectie. R12 De belangrijkste uitkomstmaat is om te meten of patiënten na een laparoscopische R13 littekenbreukcorrectie significant korter in het ziekenhuis opgenomen zijn. Patiënten die niet R14 participeren in het gerandomiseerde deel van de studie worden geregistreerd in een database. R15 Deze studie heet de ‘INCH trial’ (hoofdstuk 5). De studie loopt momenteel in een groot aantal R16 ziekenhuizen in Nederland, we hopen over een aantal jaar de uitkomsten te kunnen rapporteren. R17 Meer informatie kunt u vinden via www.inchtrial.nl. R18 R19 Omdat er geen richtlijnen zijn over welke patiënt met een littekenbreuk behandeld kan worden R20 door middel van een laparoscopische chirurgische correctie, heeft de INCH studiegroep besloten R21 deze beslissing over te laten aan de behandelend chirurg. Daarnaast zijn er verschillende open R22 chirurgische technieken om littekenbreuken te corrigeren met vergelijkbare resultaten. Welke R23 open techniek gebruikt wordt in de INCH trial wordt daarom eveneens aan de behandeld R24 chirurg overgelaten. De laparoscopische techniek om littekenbreuken te corrigeren is evenmin R25 gestandaardiseerd. In de INCH trial is de enige vereiste het gebruik van een kunststof mat met R26 een minimale overlap van 5cm over de fascie, omdat over het algemeen gedacht wordt dat R27 dit de recidief kans verlaagt. Alle participerend chirurgen hebben tenminste 50 laparoscopische R28 littekenbreukcorrecties verricht en veel van hen zijn hernia experts. R29 R30 Om de ziekte specifieke kwaliteit van leven te kunnen meten in de INCH trial is de Carolina R31 Comfort Scale (CCS) in het Nederlands gevalideerd (hoofdstuk 6). De CCS is een vragenlijst die R32 ontworpen is om de ziekte specifieke kwaliteit van leven te meten bij patiënten die een correctie R33 R34 van hun buikwandhernia ondergaan met gebruik van een kunststof matje. De lijst is in de VS R35 ontworpen en gevalideerd door Heniford et al. De vragenlijst werd vertaald en getest in patiënten R36 die een liesbreuk, navelbreuk of littekenbreuk correctie ondergingen. Aan 100 patiënten werd R37 gevraagd om 1 en 3 weken na hun operatie de vragenlijst in te vullen. De Nederlandse CCS bleek 10 R38 R39

Nederlandse samenvatting | 147 R1 een valide en klinisch relevante vragenlijst om de ziekte specifieke kwaliteit van leven te testen in R2 patiënten die een correctie ondergingen van hun buikwandhernia. De CCS zal derhalve gebruikt R3 worden in de INCH trial. R4 R5 Getracht werd na te gaan of bepaalde chirurgische aspecten van de laparoscopische R6 littekenbreukcorrectie invloed hebben op het onstaan van een recidief littekenbreuk. Er werd R7 daartoe een review verricht (hoofdstuk 7). Het gebruik van transfasciale hechtingen, de mate van R8 R9 overlap van de mat over de fascie en het type mat werden geanalyseerd. Er werd geen specifieke R10 parameters geïdentificeerd die het ontstaan van een recidief beïnvloeden. R11 R12 Terwijl de INCH trial werd opgezet organiseerden wij de EAES Consensus Development R13 Conference over de endoscopische behandeling van liesbreuken. De laatste jaren zijn er twee R14 richtlijnen verschenen betreffende de behandeling van liesbreuken: één werd opgesteld door de R15 European Hernia Society (2009) en één door de International EndoHernia Society (2011). Beide R16 richtlijnen beschrijven het beste bewijs. Daar waar dat ontbreekt, beschrijft het de mening van R17 een groep hernia experts. R18 De aanvullende waarde van het organiseren van een Consensus Development Conference was R19 met name om te kijken wat de algemene opinie is over onderwerpen waar het aan evidence R20 ontbreekt. R21 In deze Consensus Development Conference werd de meest recente en best aanwezige R22 wetenschappelijke bewijsvoering gecombineerd met de opinie van een expert panel en de leden R23 R24 van de EAES (chapter 8). R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

148 | Chapter 10 Dankwoord R1 R2

Het boek is af! Toen Peter van den Akker eens tijdens de borrel zei dat ik alleen mocht meepraten R3 R4 over promoveren als ik ‘t zelf ook had gedaan nam ik mij voor een boek te schrijven. De afgelopen R5 jaren werkte ik daarom naast mijn opleiding tot chirurg aan dit zogenoemde ‘hobby-project’, ook R6 wel ‘werkstuk’ genoemd door mijn moeder. Dit proefschrift is tot stand gekomen met de hulp R7 van vele mensen, die ik allemaal wil bedanken, een aantal in het bijzonder. R8 R9 Dr. W.H. Schreurs, lieve Hermien, mijn werkmoeder. Ruim 7 jaar geleden nam je me aan als R10 ANIOS in het Medisch Centrum Alkmaar en hielp je me aan een onderwerp om onderzoek naar R11 te doen. De basis voor dit proefschrift werd gelegd. R12 Ik bewonder je om je chirurgische kwaliteiten, je gave om het beste uit mensen te halen en R13 om je girl power. Ik ben je erg dankbaar voor het vertrouwen dat je altijd in me hebt gehad, de R14 kansen die je me geboden hebt en de chirurgische lessen die je me hebt geleerd. Zonder jou was R15 ‘t niets geworden. Met een lach op mijn gezicht denk ik terug aan de afgelopen jaren. Ik hoop R16 je in de toekomst nog vaak te zien en te spreken en wie weet af en toe nog eens een aquarium R17 te ontdekken. R18 R19 R20 Prof H.J. Bonjer, lieve prof, ondanks jouw drukke agenda, maar met name dankzij jouw R21 wetenschappelijke gaven is ‘t gelukt; het boek is af. Bedankt voor alle mogelijkheden die je R22 me hebt gegeven om mezelf te ontwikkelen. Zowel op wetenschappelijk als op politiek als op R23 chirurgische vlak heb ik veel van je geleerd. Wat heerlijk dat je altijd denkt in mogelijkheden en R24 jonge mensen betrekt en aanspreekt alsof het je gelijken zijn. R25 De INCH trial is nog in volle gang, dus we hebben nog wel wat te doen. Hopelijk pakken we R26 die ZonMW! Ik ga mijn carrière nu eerst vervolgen daar waar jouw roots liggen, in Rotterdam. R27 Ik hoop je in de toekomst geregeld te zien en te spreken, of het nou over motorboten of over R28 wetenschap gaat! R29 R30 Drs. B.L.A.M. Langenhorst, lieve BLAM, ik weet dat je geen wetenschapper bent. Toch ben je vaak R31 het best op de hoogte van de nieuwste wetenschappelijke bevindingen binnen jouw vakgebied R32 en gaf je aanzet tot het schrijven van dit proefschrift. Met al je zo typerende, niet altijd even R33 R34 zachtzinnige uitspraken heb ik me de afgelopen jaren goed vermaakt. Ik zal nooit meer een dikke R35 vrouw kunnen opereren zonder aan je te denken. Bedankt voor alle wijze lessen die je me hebt R36 geleerd. Ik hoop dat we die eetafspraak nu nog eens maken! 10 R37 R38 R39

Dankwoord | 149 R1 Prof J. Jeekel, beste professor, elke keer dat wij elkaar zien vertelt u mij hoe waardevol het is dat R2 er ‘van dit soort spontane meisjes’ doordringen in de chirurgie. Ik vat dat op als een compliment. R3 Het is al jaren geleden dat u tegen me zei, “als er ooit een boek komt, dan moet je me wel vragen R4 voor de commissie!”. Zie hier, het boek is af en ik voel mij zeer vereerd dat u in de commissie R5 plaatsneemt. R6 R7 Prof G. Kazemier, beste Geert, wat een prettige verrassing om je tijdens een tweede ronde VUMC R8 R9 te leren kennen, niet alleen vanwege de chirurgische lessen, maar ook vanwege de gezelligheid. R10 Ik heb veel geleerd van je kennis, kunde en je kijk op de wereld. Hoewel ik mijn carrière richting R11 de 7 stuur (in jouw ogen het hoogst haalbare in de periferie) bewonder ik jouw grenzeloze drive R12 om de 10 te zijn. Ik hoop je nog vaak tegen te komen voor een rondje slap ouwehoeren, maar R13 ook voor serieus advies. Bedankt dat je wil plaatsnemen in mijn commissie. R14 R15 Prof. M.A. Cuesta, beste Miguel, wat een geluk dat ik nog door je ben opgeleid en een stukje R16 van je kunde mee kan nemen in mijn verdere carrière. Het ‘knuffelen met die weefsels’ schiet R17 vaak door mijn hoofd als er een stukje van de operatie even lastig is. Ook bij het gebruik van een R18 Vicryl mat denk ik aan jou. Ik bewaar goede herinneringen aan een skivakantie waar Jaap Bonjer, R19 jij en ik de rest waren kwijtgeraakt en ons een dag lang hebben vermaakt met skiën, stiekeme R20 borreltjes in de lift en het eten van taartjes bij de open haard. Ik hoop op dat glas witte wijn op R21 een terras in het Vondelpark. Bedankt dat je in mijn commissie wilt plaatsnemen. R22 R23 R24 Prof. J. Lange, beste professor, zijdelings hebben we elkaar vaak gezien, direct herinner ik mij R25 met name één keer. Het was in Rotterdam, waar ik bij Jaap achterop de NS-scooter naar het R26 restaurant kwam waar we, samen met Joost Bruggeman gingen eten. Scooters en Scaffolds werd R27 de werknaam. Fantaseren over allerlei (wetenschappelijke) projecten blijft heerlijk om een avond R28 mee te vullen. Dank dat u plaats wilt nemen in mijn commissie. R29 R30 Prof. H. van Goor, u viel mij op vanwege uw wat oostelijk klinkende accent, wat een beetje voelde R31 als thuis. U blijkt inderdaad uit Zwolle te komen, waar ook mijn roots liggen. Wellicht dat het R32 mij ook daarom een goed idee leek u voor mijn commissie uit te nodigen. Veel dank dat u de R33 uitnodiging geaccepteerd heeft. Natuurlijk zal ik luisteren naar de inhoud van uw vragen en niet R34 naar uw uitspraak;) R35 R36 R37 R38 R39

150 | Chapter 10 Dr. B.J. Dwars, lieve Dr.D! Wat een feest om je in de buurt te hebben en heerlijk om je af en toe R1 te kunnen huggen. Bedankt voor de gezellige borrels en etentjes in binnen- en buitenlandse R2 steden. Ik hoop dat we elkaar nog vaak tegen zullen komen. Bedankt dat je er bent nu ik mijn R3 R4 proefschrift ga verdedigen. R5 R6 Aan mijn voormalig bazen in het Medisch Centrum Alkmaar. Ik heb genoten van alle serieuze en R7 gezellige momenten in een ziekenhuis dat voelt als mijn tweede thuis. Ik ben er klaar voor om R8 nu als chirurg aan de slag te gaan en het nest uit gegooid te worden. Bedankt daarvoor. Ik hoop R9 jullie nog vaak te zien en te spreken. R10 R11 Stafleden VUMC, bedankt voor de academische verrijking en gezelligheid tijdens mijn jaren in het R12 VU Medisch Centrum. Misschien heeft het zo moeten zijn dat er weer eens iemand van 020 naar R13 010 gaat in plaats van andersom. Lang leve de Zuidas. R14 R15 Aan al mijn (oud-)collega’s in het VUMC en MCA; heel veel dank voor de gezellige opleidingsjaren. R16 Een paar mensen wil ik in het bijzonder bedanken. De slechte mensen club; Ivar, Ruby en Paula, R17 voor een heerlijk begin van de opleiding met jullie aan mijn zij. Hoewel het leven is veranderd R18 R19 (jee wat zijn we oud aan het worden..) hoop ik snel weer eens een borrel met jullie te drinken. R20 De mannen uit de tijd van de mannen, Nike Hanneman, Gisela Moormann, David Heineman R21 en Joost Bruggeman, je weet toch. Boffen was dat. Nike, wat fijn om zoveel jaar samen onze R22 opleiding te volgen. Bedankt voor alle gezelligheid de afgelopen jaren. Wat een feest dat we nu R23 weer samen gaan werken, ik zie er naar uit! R24 Babs Zonderhuis, ik kwam je tegen in de VU.. net zo’n regelnicht als ik en nog gezellig ook. Wat R25 fijn dat je m’n vriend werd. R26 Baukje van den Heuvel, wat een gezelligheid dat jij ook naar de VU kwam vanuit Maastricht. Als R27 geen ander begreep jij hoe heftig het is om naast je opleiding ook te promoveren. Ik hoop dat ik R28 in de buurt kom van jouw fantastische prestatie van afgelopen winter. R29 R30 Nadine, Charlotte en Jort, zoals jullie weten blijf ik graag betrokken bij alle ins en outs van de R31 INCH trial, maar ik ben heel blij dat jullie de praktische uitvoering van mij hebben overgenomen. R32 Bedankt! R33 R34 Nadine, zet m op met dat boek over de buikwand, je kunt het! R35 R36 Elly de Lange en Tjeerd van der Ploeg, bedankt voor de statistische hulp bij al het onderzoek. 10 R37 R38 R39

Dankwoord | 151 R1 Ron de Hoon, Annemarie Kerstens en het secretariaat chirurgie, met name Ilse Kruit; bedankt R2 voor de ondersteuning, adviezen en hulp in het VUMC. Jullie maken het leven makkelijker. R3 R4 Medewerkers poli chirurgie van het Medisch Centrum Alkmaar, en in het bijzonder Yvonne R5 Ottenbros, bedankt voor het maken van alle controle afspraken, opvragen van statussen en R6 andere secretariële klussen. Het is een verademing dat jullie zo lekker proactief zijn. R7 R8 R9 Inge Schouten, Judith Spronk en Peter de Mooij, heel veel dank voor alle ondersteuning bij vele R10 aspecten van het onderzoek en al het geregel er omheen. R11 R12 Aan mijn lieve vrienden, bedankt dat ik bijna nooit met jullie over onderzoek hoefde te praten. R13 Erg lief dat jullie af en toe vroegen waar het ook alweer over ging en dat dan ook onthielden. Ik R14 voel mij een gelukkig mens met jullie om mij heen. R15 In het bijzonder: R16 Berber en Maartje, jullie zijn als mijn familie, bedankt voor de onvoorwaardelijke liefde en steun. R17 Michiel en Yvonne, wat heerlijk dat we het leven een beetje kunnen delen. R18 Jeroen en Ron, ik hoop dat we nog jaren samen blijven feesten, dank dat jullie er zijn. R19 Evelien, ik vind het fijn dat we elkaar zo goed blijven begrijpen, dank dat je m’n vriend bent. R20 R21 Paranimfen R22 Lieve Yvonne, al jaren praten we over relaties, studie, carrière, geluk, ambitie, familie, vrienden en R23 R24 hoe dat samengaat. Het leek mij daarom een voor de hand liggende keuze om jou te vragen om R25 mijn paranimf te zijn. Dank dat je me, ook op het moment van mijn verdediging bijstaat. R26 Lieve Swa, mijn zusje, Maartje Nijlpaard. Je moet niet denken dat het wegpoetsen van mijn S R27 in verhouding staat tot het wegpoetsen van jouw S. Ik ben trots op hoe je het leven het hoofd R28 biedt en heel blij dat je tijdens mijn verdediging naast me wilt staat. Dr(s) P & Dr(s) P forever! R29 Ik hou van jou. R30 R31 Lieve Arjen en Bas, dank dat we het zo goed hebben samen. Bijzonder is dat. R32

R33 Lieve Wilma en Roel, wat fijn dat jullie mijn nieuwe familie zijn. R34 R35 Lieve Stan, het heeft een tijdje geduurd voor wij elkaar op waarde konden schatten, maar het R36 resultaat is er. Dank voor je rust, interesse en zorgzaamheid. Dank dat je mamma zo gelukkig R37 maakt. R38 R39

152 | Chapter 10 Lieve mamma, wat jammer dat pappa er niet is, de zoveelste mijlpaal zonder hem. Hij weet vast dat R1 we het goed doen en is daar ongetwijfeld trots op. Ik bewonder je om je doorzettingsvermogen, R2 je gave de kleine dingen te zien en om je onuitputtelijke attentheid. Bedankt dat we het samen R3 R4 zo goed hebben. Ik hou van jou. R5 R6 Liefste Margo, you and me. Het leven is zoveel leuker met jou. Ik hou van je. R7 James, wat een feest dat je in ons leven bent gekomen, ik hoop dat we nog oneindig veel plezier R8 gaan beleven samen. R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 10 R37 R38 R39

Dankwoord | 153 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39

154 | Chapter 10 Curriculum Vitae R1 R2

Marijn Poelman werd op 5 juni 1981 geboren in Groningen als oudste dochter van Nelleke R3 R4 Trooster en Martin Poelman. Nadat ze haar jeugd in Zwolle had doorgebracht en daar haar R5 Atheneum diploma behaalde, ging ze in 1999 geneeskunde studeren in Maastricht. Tijdens haar R6 studie geneeskunde genoot zij met volle teugen van het studentenleven en reisde veel. Ze volgde R7 delen van haar studie in de Phillipijnen, Spanje en Ecuador. R8 Na het afronden van haar studie begon zij in 2006 als ANIOS heelkunde voor de tropenopleiding R9 in het Tergooi Ziekenhuis in Blaricum, waar al doende steeds duidelijker werd dat zij verder wilde R10 in de chirurgie. Met dat doel voor ogen werd zij ANIOS heelkunde in het Medisch Centrum R11 Alkmaar, waar al vrij snel de basis voor dit proefschrift werd gelegd. R12 In januari 2008 startte zij met de opleiding tot chirurg in het Medisch Centrum Alkmaar (opleider R13 dr. W.H. Schreurs) en het VU Medisch Centrum (opleider prof.dr. J.A. Rauwerda/dr. D.L. van R14 der Peet). Tijdens haar opleiding heeft zij het onderzoek naar mensen met een littekenbreuk R15 voorgezet, wat geresulteerd heeft in dit proefschrift. R16 Zij heeft haar opleiding tot gastro-intestinaal chirurg in mei 2014 afgerond. Ze is in juni 2014 R17 gestart als chef de clinique bij Maatschap Chirurgen Rotterdam Zuid. R18 R19 Marijn woont samen met Margo Dijkman en hun zoon James in Amsterdam. R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 10 R37 R38 R39

Curriculum Vitae | 155 ABDOMINAL WALL HERNIA Uitnodiging

Voor het bijwonen van de openbare verdediging van ABDOMINAL mijn proefschrift getiteld

Improving surgical care Abdominal Wall Hernia WALL Improving surgical care

Op vrijdag 26 september 2014 om 13.45 uur in de Aula van de Vrije Universiteit. HERNIA De Boelelaan 1105, 1081 HV in Amsterdam. Improving surgical care Receptie na afloop ter plaatse

Promovenda: Marijn Poelman Gerard Brandtstraat 3-4 1054JH Amsterdam 0641013388 [email protected]

Paranimfen: Maartje Poelman [email protected] Yvonne Bors [email protected] Marijn Poelman De pdf van het proefschrift is te downloaden op: Marijn Poelman www.inchtrial.nl