Prophylactic Negative Pressure Wound Therapy and Wound Complication After Cesarean Delivery in Women with Class II Or III Obesit

377 , ScD , MS , MD ClinicalTrials.gov, Obesity has a signif- 1 7) for the standard dress- .35, relative risk 1.52, 95% 6 5 P 8) for the prophylactic negative .87). 6 5 P , Hayley J. Jones, OBSTETRICS & GYNECOLOGY 2014 statistics. – In this randomized controlled trial that MD , Marlene B. Goldman, PhD Women were recruited between January 5, ] 30 or higher) continues to increase, affecting 2 he prevalence ofindex obesity (defined [BMI, as calculated body mass as weight (kg)/[height CI 0.66–3.52). There were noof differences composite in wound the complications occurrence betweenprophylactic women using negative[31%]) pressure compared with women wounddressing who (24/81 received therapy [30%], the standard (25/80 RESULTS: 2015, and January 7,on 2017, admission from was two 44.9wound sites. therapy ( The group and mean 43.4 BMI ( ing group. There wereobserved no differences in superficial thewomen occurrence using of surgical prophylactic negativeapy site pressure (12/80 [15%]) wound compared ther- with infections womenstandard who dressing received (8/81 between the [10%], CONCLUSION: did not achieve fullobserve anticipated a enrollment, decrease we inafter did superficial cesarean not surgical delivery site inprophylactic infections obese negative women pressure with wound the therapy. useCLINICAL of NCT02390401. TRIAL REGISTRATION: months, an interimand analysis the decision for was futility made to was halt conducted the study. (m)] icant effect on many aspects of pregnancy, including (Obstet Gynecol 2018;132:377–84) DOI: 10.1097/AOG.0000000000002744 T approximately 40% ofStates adult according to femalesPrevention Centers in 2013 for the Disease Control United and , June L. Fung, MD , Zachary T. Spalding, MD s requirements for ’ decision as to what the ’ he American College of Obstetricians t by MPH , ª Original Research , Rebecca H. Evans, , Ellen M. Joyce, MD PhD MD s comments. The authors ’ Copyright Unauthorized reproduction of this article is prohibited. To compare the occurrence of superficial and Gynecologists. Published by Wolters Kluwer Health, Inc. We conducted a randomized controlled, non-

Todd A. MacKenzie, The authors did not report any© potential 2018 conflicts by of theby interest. American Wolters College Kluwer of Health, ObstetriciansISSN: Inc. and 0029-7844/18 All Gynecologists. rights Published reserved. Corresponding author: Kristina A.Gynecology, Wihbey, The MD, Geisel Department School ofConcord, of Obstetrics NH Medicine and 03301; at email: Dartmouth, [email protected]. 189Financial N Disclosure Main Street, authorship. Received February 6, 2018. Received15, in revised 2018. form May 4, 2018. Accepted May manuscript contained was final. Each author has indicated that he or she has met the journal and Elisabeth Erekson, VOL. 132, NO. 2, AUGUST 2018 with the company beforenot manuscript submission; bound however, to the incorporate investigators KCI were Geisel School of Medicine at Dartmouth,The Lebanon, devices New used Hampshire. infrom KCI this Medical study (San weredesign, Antonio, Texas). provided data KCI collection, by Medical or an had data unrestricted no analysis. role research in Final grant the results study of the study were shared However, after low enrollment of 166 womenFrom over the 24 DepartmentsScience and of the Dartmouth Obstetrics Institute for and Health Policy Gynecology and Clinical and Practice, Biomedical the Data was occurrence of a superficialassumed surgical site a infection. We superficial surgicalrate site of infection occurrence 20% and intended to recruit 400 women. placed at the time of primaryin closure obese at cesarean women delivery withhigher body (ie, mass class indexes II (BMI) and of III 35 obesity). or Our primary outcome after cesarean delivery. Methods: blinded, two-center study of prophylacticsure negative therapy pres- compared with standard surgical dressings OBJECTIVE: surgical site infectionslactic in negative obese pressure women therapy with using standard prophy- dressings Kristina A. Wihbey, III Obesity A Randomized Controlled Trial Cesarean Delivery in Women With Class II or Prophylactic Negative Pressure Wound Therapy and Wound Complication After Cesarean Delivery:

Downloaded from https://journals.lww.com/greenjournal by BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD3TDbD+Y6NAIH9mhZe+OAo47wPbjrTWLsWPNit4YQiE6KcLXJXE7nthw== on 09/24/2018 Downloaded from https://journals.lww.com/greenjournal by BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD3TDbD+Y6NAIH9mhZe+OAo47wPbjrTWLsWPNit4YQiE6KcLXJXE7nthw== on 09/24/2018 increased need for cesarean delivery. In addition, obe- Control and Prevention using prophylactic negative sity is a well-recognized risk factor for the develop- pressure wound therapy compared with standard ment of postoperative surgical site infections and dressings after cesarean delivery. other wound complication.2,3 In the late 1990s, Tran et al4 found a 9.8% surgical site infection rate among MATERIALS AND METHODS obese women after cesarean delivery with risk of We conducted a randomized controlled, nonblinded, infection doubling for every five-unit increment of multicenter study of prophylactic negative pressure BMI. wound therapy compared with standard surgical Prophylactic negative pressure wound therapy dressings placed at the time of primary closure in as a means of reducing wound infection has been a cesarean delivery. Institutional review board explored as primary dressings in the orthopedic and approval was obtained from the Dartmouth Commit- cardiothoracic fields, but limited data have been tee for the Protection of Human Subjects on April 21, published in the peer-reviewed literature report on 2015 (#00005211) and from the Southern New use with abdominal incisions. Two meta-analyses Hampshire Medical Center Clinical Trials Office recently combined published peer-reviewed manu- (#2015-01). This trial was registered with clinical- scripts, meeting abstracts, and data published on trials.gov (Clinical Trial Registration: intranet websites to determine the effectiveness of NCT02390401). Women were recruited and con- prophylactic negative pressure wound therapy at sented to participate in this study before the onset of the time of cesarean delivery.5,6 Unfortunately, active labor during any routine prenatal visit or inpa- these two meta-analyses reported conflicting data tient admission. on the effectiveness of prophylactic negative Women were recruited from two hospitals, pressure. Dartmouth-Hitchcock Medical Center (a rural tertiary Therefore, the objective of this randomized con- care center with a level III neonatal intensive care trolled trial was to compare the occurrence of unit) and Southern New Hampshire Medical Center superficial surgical site infections in women with class (a community-based hospital with a level II neonatal II or III obesity as defined by the Centers for Disease intensive care unit).

Fig. 1. Flow diagram. Wihbey. Prophylactic Negative Pressure Wound Therapy. Obstet Gynecol 2018.

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Copyright ª by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. Women were eligible for inclusion if they under- Table 1. Demographics and Characteristics of went cesarean delivery for a viable neonate and their Participating Women BMI on admission to the labor and delivery floor was 35 or higher. All women undergoing cesarean deliv- NPWT Standard ery were eligible for inclusion. Women were ap- Dressing Dressing Characteristic (n580) (n586) proached only for participation and consent in this study before active labor Additionally, women who Site were younger than 18 years old, did not speak A 64 (80) 72 (84) English, had an allergy to silver or adhesives products, B 16 (20) 14 (16) Maternal characteristics or who had a skin incision that would not fit the Maternal age (y) 31.066 30.265 device or standard dressing (eg, “T” skin incision) Race were excluded. White 76 (99) 81 (99) Abdominal preparation for cesarean delivery was Black 1 (1) 0 (0.0) performed with 2% chlorhexidine alcohol solution. Other 0 (0) 1 (1) Ethnicity All women received intravenous antibiotics before Hispanic 2 (2) 0 (0) skin incision consistent with American College of Parity Obstetricians and Gynecologists’ guidelines7 with the 1 20 (25) 34 (40) majority of women receiving cefazolin or clindamycin 2 37 (46) 23 (27) with gentamicin if allergic. Surgical techniques were 3 18 (23) 23 (27) 4 or more 5 (6) 6 (7) left to the discretion of the surgeon. Women were Gestational age (wk) discharged postoperatively by the primary team, usu- 28 or less 1 (1) 3 (3) ally on the third or fourth postoperative day, irrespec- Greater than 28–37 21 (29) 17 (22) tive of study assignment. All women were scheduled Greater than 37–42 51 (70) 59 (74) to return for a wound assessment on postoperative Greater than 42 0 (0) 0 (0) – Multiple gestation 4 (5) 5 (6) day 5 7. Prior cesarean deliveries If randomized to prophylactic negative pressure 0 38 (48) 44 (51) wound therapy, the device was applied at the time of 1 33 (41) 30 (35) primary skin closure at cesarean delivery. It was 2 7 (9) 11 (13) placed over the closed surgical incision under sterile 3 or more 2 (3) 1 (1) BMI (kg/m2) 44.968 43.467 conditions and was removed between postoperative BMI category (kg/m2) day 5 and 7 at the time of incision check. 35–40 30 (38) 31 (38) The standard dressing after cesarean delivery was Higher than 40 to 50 31 (39) 40 (49) also applied using a sterile technique. If subcuticular Higher than 50 19 (24) 15 (19) 6 6 closure was used, sterile slim adhesive strips (also Preoperative hct (%) 30.4 10 31.3 9 Preoperative anemia (hct less than 58 (73) 54 (63) known as Steri-Strips) were applied. For both sub- 36%) cuticular and staple closure, the dressing consisted of Antenatal steroids 8 (10) 11 (13) a sterile nonadherent wound dressing (also known as Diabetes mellitus Telfa), a sterile gauze, and a waterproof transparent Type I diabetes mellitus 1 (1) 1 (1) adhesive dressing (also known as Tegaderm). The Type II diabetes mellitus 9 (12) 4 (5) Gestational diabetes mellitus 11 (15) 20 (25) standard dressing was removed on postoperative day Hypertension 2. Chronic hypertension 6 (8) 4 (5) A randomization program (www.randomization. Gestational hypertension 6 (8) 3 (4) com, Alberta, Canada) was used to generate sealed Preeclampsia with severe features 6 (8) 9 (11) opaque envelopes with study assignment. Women Current smoker 14 (18) 13 (15) were randomized at the conclusion of the cesarean NPWT, prophylactic negative pressure wound therapy; BMI, body mass index; hct, hematocrit. delivery, during skin closure, when the envelopes Data are n (%) or mean6SD. were opened by a circulating operating room nurse. Two randomization strata were created using per- muted blocks with varying block sizes for women with Our primary outcome was occurrence of super- BMIs from 35 to less than 40 and women with BMIs ficial surgical site infection, defined according to of 40 or higher and for each site to ensure equal dis- Centers for Disease Control and Prevention criteria8 tribution of study allocation across these two separate as infection involving only the skin or subcutaneous BMI categories and sites. tissue occurring within 30 days of surgery with at least

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Intrapartum Event NPWT Dressing (n580) Standard Dressing (n586)

Reason for admission to labor and delivery Spontaneous labor 51 (65) 54 (65) Induction of labor 18 (23) 22 (27) Scheduled cesarean delivery 9 (12) 7 (8) Duration of rupture of membranes (min) 2116407 2266440 Duration of rupture of membranes (h) Less than 18 74 (93) 76 (88) 18 or more 6 (8) 10 (12) Chorioamnionitis 1 (1) 0 (0) Intraoperative variables Operative time (incision to stop, min) 82.3625 80.4623 Type of anesthesia Spinal–epidural 71 (89) 79 (93) General 9 (11) 6 (7) Skin incision Pfannenstiel 55 (86.0) 68 (93.2) Vertical midline 9 (14) 5 (7) Skin closure Subcuticular 58 (91) 67 (93) Staples 6 (9) 5 (7) Estimated blood loss (mL) 9366253 9666318 Postpartum hemorrhage (greater than 1,000 mL) 38 (48) 39 (45) Intraoperative blood transfusion 0 (0) 3 (4) Maternal procedures with delivery Tubal ligation 29 (36) 21 (24) Peripartum hysterectomy 0 (0) 0 (0) NPWT, prophylactic negative pressure wound therapy. Data are n (%) or mean6SD. oneofthefollowing:1)purulentdrainagefromthe distributions were used as appropriate. We first com- wound or 2) organism identified by culture or wound pleted an observed outcome analysis based on deliberately opened by the surgeon. Patients also observed outcomes for the women who completed needed to have at least one of the following symp- their 1-week postoperative incision check. We then toms: pain, swelling, or erythema. Our secondary calculated an unadjusted relative risk and 95% CI for outcome was a composite wound complication, the primary outcome. We then completed a second including superficial, deep, or organ-space surgical outcome analysis for all women who were random- site infection; wound dehiscence; seroma; or hema- ized and received their intended treatment despite toma that occurred within 30 days of surgery. Other lack of follow-up at the 5- to 7- day incision check secondary outcomes included 30-day readmission, by imputing missing data. We assumed that all 30-day reoperation, and need for antibiotic treatment women who were lost to follow-up had developed for any reason (eg, mastitis, urinary tract infection, superficial surgical site infections. For the secondary pyelonephritis). We also examined length of stay outcome of composite wound complication, we after cesarean delivery and rates of breastfeeding at assumed that complications that would not require discharge this seems to have been erroneously dupli- readmission happened (eg, seroma, hematoma, or cated. We had already stated this earlier in the text. wound dehiscence) and we assumed that complica- Additional outcomes were determined by chart tions that would generally require inpatient readmis- review. sion did not happen (eg, deep surgical site infections Standard statistical methods such as frequency or organ-space surgical site infections). Finally, we distributions and measures of central tendency were conducted two subgroup analyses of women with used to evaluate the demographic and clinical BMIsof40to50andBMIsof50orhighertosee characteristics of the participants. Pearson x2,Fisher whether these groups had differences in superficial exact test, and Student t test for parametric distrib- surgical site infections not observed in the larger uted variables and Kruskal-Wallis for nonparametric cohort.

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Intention-to-Treat Observed Assumed Superficial SSI if Outcomes Lost to Follow-up NPWT Dressing Standard Dressing Standard Dressing Complication (n580) (n581) P (n586) P

Superficial SSI 12 (15) 8 (10) .35 13 (15) .98 Composite wound complication 25 (31) 24 (30) .87 29 (34) .73 Deep SSI 0 (0) 0 (0) — 0 (0) — Organ SSI 1 (1) 4 (5) .37 4 (5) .37 Seroma 7 (9) 6 (7) .78 11 (13) .46 Hematoma 2 (3) 4 (5) .68 9 (11) .06 Wound dehiscence 14 (18) 13 (16) .84 13 (15) .83 Readmission 3 (4) 5 (6) .72 5 (6) .72 Reoperation 1 (1) 1 (1) 1.00 1 (1) 1.00 Antibiotic treatment SSI (superficial, deep, organ- 14 (18) 10 (12) .39 17 (20) 1.00 space) UTI 1 (1) 2 (3) 1.00 7 (8) .17 Pyelonephritis 0 (0.0) 0 (0) 5 (6) .06 Mastitis 0 (0) 0 (0) 5 (6) .06 Hospital length of stay (d) 3.2 (3–4) 3.2 (2–4) .51 3.2 (2–4) .51 Breastfeeding at discharge 52 (65) 63 (73) .31 63 (73) .31 SSI, surgical site infection; NPWT, negative pressure wound therapy; UTI, urinary tract infection. Data are n (%) or median (interquartile range) unless otherwise specified. Composite wound complication includes superficial SSI, deep SSI, organ-space SSI, seroma, hematoma, or wound dehiscence. If lost to follow-up, women were assumed to have developed superficial SSI, seroma, and hematoma. Conditions that required hospitalization (eg, deep SSI, organ-space SSI, and wound dehiscence) were assumed not to have occurred in women lost to follow-up.

At the time of study initiation (April 2015), based infection, as predicted in the original sample size on the current literature, we assumed an occurrence of calculation (20% superficial surgical site infection in superficial surgical site infection of 20% of obese women with standard dressing and 10% in women women undergoing cesarean delivery.4,9,10 We deter- with prophylactic negative pressure wound therapy), mined that 400 women (200 prophylactic negative our study’s power to detect a difference between the pressure wound therapy, 200 standard dressing) two interventions would be 29% at completion of would need to be recruited to have an 80% power enrollment of our 400 participants. If we assumed that to detect a 50% decrease in superficial surgical site the primary outcome in the remaining 244 women infection (assuming P,.05). We anticipated that would be the same as prevalence observed in the first enrollment across the two sites would take 24 months. 166 women who had already completed the study, ’ At the completion of the anticipated 2 years of our study s power to detect a difference between the recruitment, 166 women out of a planned 400 (42%) two interventions would be less than 0.1%. Therefore, had been enrolled in the study. This was likely the the determination of the data safety monitoring board result of the limitations of women’s ability to return was that continued enrollment to original recruitment for device removal and incision evaluation 5–7 days targets was futile and the recommendation was made after delivery (many had been transported to the ter- to halt further enrollment and disseminate our findings. tiary recruiting site and lived a long distance from this site). As a result of this low enrollment, the study’s data safety monitoring board recommended an RESULTS unplanned interim analysis with futility calculation Women were recruited between January 5, 2015, and to determine whether the study should continue. January 7, 2017. A total of 166 women were random- We anticipated that to reach our original recruit- ized, 163 received their allocated treatment, and 161 ment goals, we would need to continue our study for (80 prophylactic negative pressure wound therapy and 34 additional months. If we assumed that observed 81 standard dressing) returned for their postoperative outcomes in the remaining 244 women would wound assessment approximately 1 week after cesar- develop the primary outcome, superficial surgical site ean delivery (Fig. 1). The two randomization groups

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Copyright ª by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. Table 4. Demographics and Clinical Characteristics of Women With Superficial Surgical Site Infection After Cesarean Delivery (N5161)

Characteristic Superficial SSI (n520) No Superficial SSI (n5141) P

Group .32 Prophylactic negative pressure wound therapy 12 (60) 68 (48) Standard dressing 8 (40) 73 (51) Site .09 A 19 (95) 112 (79) B 1 (5) 29 (21) Maternal characteristics Maternal age (y) 31.066 30.766 .85 Race .24 White 19 (95) 133 (99) Black 1 (5) 0 (0) Other 0 (0) 1 (1) Ethnicity .23 Hispanic 1 (5) 1 (1) Parity .66 1 9 (45) 43 (31) 2 6 (30) 53 (38) 3 4 (20) 36 (26) 4 or more 1 (5) 9 (6) Gestational age (wk) .87 28 or less 0 (0) 4 (3) Greater than 28–37 5 (28) 32 (25) Greater than 37–42 13 (72) 93 (72) Greater than 42 0 (0) 0 (0) Gestational age (d) 261621 260624 .82 Prior cesarean deliveries .03 0 16 (80) 66 (47) 1 2 (10) 57 (40) 2 2 (10) 16 (11) 3 or more 0 (0) 2 (1) BMI (kg/m2) 46.968 43.567 .06 BMI category (kg/m2) .02 35–40 3 (15) 58 (41) Higher than 40 17 (85) 83 (59) Preoperative serum hct (%) 34.866 30.2610 .04 Preoperative anemia (serum hct less than 36%) 9 (45) 101 (72) .02 Antenatal steroids 4 (20) 15 (11) .26 Diabetes mellitus .63 Type I diabetes mellitus 0 (0) 2 (2) Type II diabetes mellitus 3 (16) 10 (8) Gestation diabetes mellitus 3 (16) 27 (21) Hypertension Chronic hypertension 2 (10) 8 (6) .36 Gestational hypertension 1 (5) 8 (6) 1.00 Preeclampsia with severe features 2 (10) 13 (9) 1.00 Current smoker 3 (15) 23 (16) 1.00 Labor Reason for admission labor and delivery .79 Spontaneous labor 12 (67) 83 (67) Induction of labor 5 (28) 27 (22) Scheduled cesarean delivery 1 (6) 14 (11) Duration of rupture of membranes (min) 2726457 216 (425) .59 Duration of rupture of membranes (h) 1.00 Less than 18 18 (90) 127 (90) 18 or more 2 (10) 14 (10) Chorioamnionitis present at the time of delivery 0 (0) 1 (1) 1.00

(continued)

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Intraoperative variables Fetal weight (g) 3,19261,088 3,1796971 .96 1-min Apgar score 6.563 7.262 .15 5-min Apgar score 8.661 8.461 .61 Operative time (min) 86.3628 80.7624 .33 Type of anesthesia .10 Spinal–epidural 16 (80) 129 (92) General 4 (20) 11 (8) Skin incision .21 Pfannenstiel 19 (100) 100 (89) Vertical midline 0 (0) 13 (12) Skin closure 1.00 Subcuticular 18 (95) 103 (92) Staples 1 (5) 9 (8) Estimated blood loss (mL) 9556309 9496289 .93 Postpartum hemorrhage (greater than 1,000 mL) 9 (45) 65 (46) 1.00 Intraoperative blood transfusion 0 (0) 3 (2) 1.00 Concomitant procedures 1.00 Tubal ligation 6 (30) 42 (30) Peripartum hysterectomy 0 (0) 0 (0) SSI, surgical site infection; BMI, body mass index; hct, hematocrit. Data are n (%) or mean6SD. were similar in regard to maternal characteristics and there were no differences in the occurrence of observed intrapartum and intraoperative events (Tables 1 and 2). superficial surgical site infections in women using the Twelve percent of women (20/161) completing prophylactic negative pressure wound therapy (21% the 1-week incision check experienced superficial [4/19]) compared with women receiving standard dress- surgical site infection. There were no statistically ings (20% [3/15], P..99). significant differences in the occurrence of observed Risk factors for superficial surgical site infection superficial surgical site infections between women are explored in Table 4. In addition to maternal BMI using prophylactic negative pressure wound therapy category, number of prior cesarean deliveries and pre- (12/80 [15%]) compared with women who received operative anemia (serum hematocrit less than 36%) the standard dressing (8/81 [10%], P5.35; Table 3; were both associated with increased postcesarean relative risk 1.52, 95% CI 0.66–3.52). Assuming that superficial surgical site infection (Table 4). all women who were lost to follow-up developed There were no statistically significant differences superficial surgical site infection, there still would observed for length of stay after delivery and breastfeed- not have been a statistically significant difference in ing at the time of hospital discharge between women the occurrence of superficial surgical site infection with prophylactic negative pressure wound therapy and between groups (12/80 [15%] vs 13/86 [15%], P5.98). standard dressings. Fifteen percent of women (12/80) There were no significant differences in the occur- with the prophylactic negative pressure wound therapy rence of composite wound complications between device had it removed early: five women for local skin women using prophylactic negative pressure wound irritation, six women because the pump stopped work- therapy (25/80 [31%]) compared with women who ing, and one additional woman requested early removal. received the standard dressing (24/81 [30%], P5.87). In a subgroup analysis of the 71 women with BMIs of DISCUSSION 40 to 50, there were no statistically significant differences In this randomized controlled trial, we did not observe observed in superficial surgical site infections in the a decrease in superficial surgical site infection after women using the prophylactic negative pressure wound cesarean delivery in obese women with the use of therapy (7/31 [23%]) compared with women receiving prophylactic negative pressure wound therapy. Even in standard dressings (7/40 [18%], P5.77). In a subgroup a subgroup analysis of morbidly obese (BMI of 40 to 50) analysis of the 34 women with BMIs higher than 50, and the most obese women (BMI higher than 50), who

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Copyright ª by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited. are considered to be at significantly higher risk of REFERENCES surgical site infection and wound complication based 1. Flegal KM, Kruszon-Moran D, Carroll MD, Fryar CD, Ogden on published literature (Tran et al), we did not find CL. Trends in obesity among adults in the United States, 2005 – a difference in the occurrence of superficial surgical site to 2014. JAMA 2016;315:2284 91. infection with the use of prophylactic negative pressure 2. El-Chaar D, Finkelstein SA, Tu X, Fell DB, Gaudet L, Sylvain J, et al. The impact of increasing obesity class on obstetrical out- wound therapy; however, the results of these subgroup comes. J Obstet Gynaecol Can 2013;35:224–33. analyses are limited by small numbers. 3. Myles TD, Gooch J, Santolaya J. Obesity as an independent risk Our study was limited by slow enrollment and factor for infectious morbidity in patients who undergo cesarean therefore failure to reach our planned sample size. delivery. Obstet Gynecol 2002;100:959–64. The two limiting factors in our enrollment were the 4. Tran TS, Jamulitrat S, Chongsuvivatwong V, Geater A. Risk need to consent women before active labor to ensure factors for postcesarean surgical site infection. Obstet Gynecol 2000;95:367–71. women could give informed consent free from pain 5. Smid MC, Dotters-Katz SK, Grace M, Wright ST, Villers MS, and the need for patients to return for an incision Hardy-Fairbanks A, et al. Prophylactic negative pressure wound check 5–7 days after their delivery. As a tertiary cen- therapy for obese women after cesarean delivery: a systematic ter for a large rural geographic catchment area, many review and meta-analysis. Obstet Gynecol 2017;130:969–78. women delivering at our facility could not feasibly 6. Yu L, Kronen RJ, Simon LE, Stoll CRT, Colditz GA, Tuuli return for an incision check after discharge. MG. Prophylactic negative-pressure wound therapy after cesarean is associated with reduced risk of surgical site infection: In conclusion, we did not observe a statistically a systematic review and meta-analysis. Am J Obstet Gynecol significant difference in postcesarean superficial surgical 2018;218:200–10.e1. site infection or composite wound complications 7. Use of prophylactic antibiotics in labor and delivery. Practice between women who used the prophylactic negative Bulletin No. 120. American College of Obstetricians and Gy- – pressure wound therapy and women who received necologists. Obstet Gynecol 2011;117:1472 83. a standard dressing. There is currently a large multi- 8. National Healthcare Safety Network, Centers for Disease Con- trol and Prevention. Surgical site infection (SSI) event. centered National Institutes of Health-funded trial (Clin- Available at: http://www.cdc.gov/nhsn/pdfs/pscmanual/ icalTrials.gov Identifier: NCT03009110) to examine the 9pscssicurrent.pdf. Retrieved May 17, 2017. use of prophylactic negative pressure wound therapy for 9. Leth RA, Uldbjerg N, Nørgaard M, Møller JK, Thomsen RW. the reduction of wound complications in obese women Obesity, diabetes, and the risk of infections diagnosed in hospital after cesarean delivery with a goal of 2,850 women. and post-discharge infections after cesarean section: a prospective cohort study. Acta Obstet Gynecol Scand 2011;90:501–9. Until the results of this or other trials are published, 10. Alanis MC, Villers MS, Law TL, Steadman EM, Robinson CJ. we recommend against use of prophylactic negative Complications of cesarean delivery in the massively obese par- pressure wound therapy after cesarean delivery. turient. Am J Obstet Gynecol 2010;203:271.e1–7.

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