EDITORIAL

Obstetric anal sphincter injury: Prevention and repair The repair of anal sphincter injury continues to evolve. Consider incorporating the ideas in this editorial in your practice.

Robert L. Barbieri, MD Chair Emeritus, Department of Obstetrics and Gynecology Interim Chief, Obstetrics Brigham and Women’s Hospital Kate Macy Ladd Distinguished Professor of Obstetrics, Gynecology and Reproductive Biology Harvard Medical School Boston, Massachusetts

he rate of obstetric anal The optimal cutting cohort study of 1,302 women with an sphincter injury (OASIS) is angle for a mediolateral and vaginal , the rate Tapproximately 4.4% of vagi- episiotomy is 60 degrees of OASIS associated with midline or nal deliveries, with 3.3% 3rd-degree from the midline mediolateral episiotomy was 14.8% tears and 1.1% 4th-degree tears.1 In For spontaneous vaginal delivery, a and 7%, respectively (P<.05).7 In this the United States in 2019 there were policy of restricted episiotomy reduces study, the operative vaginal deliv- 3,745,540 —a 31.7% rate of cesar- the risk of OASIS by approximately ery rate was 11.6% and 15.2% for the ean delivery (CD) and a 68.3% rate of 30%.5 With an operative vaginal deliv- women in the midline and mediolat- vaginal delivery—resulting in approxi- ery, especially forceps delivery of a eral groups, respectively. mately 112,600 births with OASIS.2 A large fetus in the occiput posterior The angle of the mediolateral meta-analysis reported that, among position, a mediolateral episiotomy episiotomy may influence the rate 716,031 vaginal births, the risk factors may help to reduce the risk of OASIS, of OASIS and persistent postpartum for OASIS included: forceps delivery although there are minimal data from perineal pain. In one study, 330 nul- (relative risk [RR], 3.15), midline epi- clinical trials to support this practice. liparous women who were assessed siotomy (RR, 2.88), occiput posterior In one clinical trial, 407 women were to need a mediolateral episiotomy at fetal position (RR, 2.73), vacuum deliv- randomly assigned to either a medio- delivery were randomized to an inci- ery (RR, 2.60), Asian race (RR, 1.87), lateral or midline episiotomy.6 Approx- sion with a 40- or 60-degree angle primiparity (RR, 1.59), mediolateral imately 25% of the births in both from the midline.8 Prior to incision, a episiotomy (RR, 1.55), augmentation groups were operative deliveries. The line was drawn on the skin to mark the of labor (RR, 1.46), and epidural anes- mediolateral episiotomy began in the course of the incision and then infil- thesia (RR, 1.21).3 OASIS is associated posterior midline of the vaginal introi- trated with 10 mL of lignocaine. The with an increased risk for developing tus and was carried to the right side of fetal head was delivered with a Ritgen postpartum perineal pain, anal incon- the anal sphincter for 3 cm to 4 cm. The maneuver. The length of the episi- tinence, dyspareunia, and wound midline episiotomy began in the pos- otomy averaged 4 cm in both groups. breakdown.4 Complications following terior midline of the and was After delivery, the angle of the episiot- OASIS repair can trigger many follow- carried 2 cm to 3 cm into the midline omy incision was reassessed. The epi- up appointments to assess wound perineal tissue. In the women having a siotomy incision cut 60 degrees from healing and provide physical therapy. midline or mediolateral episiotomy, a the midline was measured on average This editorial review focuses on 4th-degree tear occurred in 5.5% and to be 44 degrees from the midline after evolving recommendations for pre- 0.4% of births, respectively. For the delivery of the newborn. Similarly, venting and repairing OASIS. midline or mediolateral episiotomy, the incision cut at a 40-degree angle a third-degree tear occurred in 18.4% was measured to be 24 degrees from doi: 10.12788/obgm.0099 and 8.6%, respectively. In a prospective the midline after delivery. The rates

8 OBG Management | May 2021 | Vol. 33 No. 5 mdedge.com/obgyn of OASIS in the women who had a 17%, respectively (P = .036). Experts contribute 50% to 85% of resting anal 40- and 60-degree angle incision were writing for the Society of Obstetri- tone.15 If injury to the internal anal 5.5% and 2.4%, respectively (P = .16). cians and Gynaecologists of Canada sphincter is detected at a birth with also recommend one dose of cefo- an OASIS, it is important to separately tetan or cefoxitin.10 Extended anaero- repair the internal anal sphincter to Use a prophylactic bic coverage also can be achieved by reduce the risk of postpartum rectal antibiotic with extended administering a single dose of BOTH incontinence.16 coverage for anaerobes cefazolin 2 g by intravenous (IV) infu- prior to or during your sion PLUS metronidazole 500 mg by anal sphincter repair IV infusion or oral medication.11 For Polyglactin 910 vs Many experts recommend one dose women with severe penicillin allergy, Polydioxanone (PDS) of a prophylactic antibiotic prior to, a recommended regimen is gentami- Suture—Is PDS the winner? or during, OASIS repair in order to cin 5 mg/kg plus clindamycin 900 mg Polyglactin 910 (Vicryl) is a braided reduce the risk of wound complica- by IV infusion.11 There is evidence suture that is absorbed within 56 to tions. In a trial 147 women with OASIS that for colorectal or hysterectomy 70 days. Polydioxanone suture is a were randomly assigned to receive surgery, expanding prophylactic anti- long-lasting monofilament suture one dose of a second-generation biotic coverage of anaerobes with that is absorbed within 200 days. cephalosporin (cefotetan or cefoxitin) cefazolin PLUS metronidazole sig- Many colorectal surgeons and uro- with extended anaerobic coverage nificantly reduces postoperative sur- gynecologists prefer PDS suture for or a placebo just before repair of the gical site infection.12,13 Following an the repair of both the internal and laceration.9 At 2 weeks postpartum, OASIS repair, wound breakdown is a external anal sphincters.16 Authors of perineal wound complications were catastrophic problem that may take one randomized trial of OASIS repair significantly lower in women receiv- many months to resolve. Administra- with Vicryl or PDS suture did not ing one dose of prophylactic antibi- tion of a prophylactic antibiotic with report significant differences in most otic with extended anaerobe coverage extended coverage of anaerobes may clinical outcomes.17 However, in this compared with placebo—8.2% and help to prevent wound breakdown. study, anal endosonographic imag- 24.1%, respectively (P = .037). Addi- ing of the internal and external anal tionally, at 2 weeks postpartum, sphincter demonstrated more inter- purulent wound discharge was sig- Prioritize identifying and nal sphincter defects but not external nificantly lower in women receiving separately repairing the sphincter defects when the repair was antibiotic versus placebo, 4% and internal anal sphincter performed with Vicryl rather than The internal anal sphincter is a smooth PDS. The investigators concluded that muscle that runs along the outside comprehensive training of the sur- of the rectal wall and thickens into a geon, not choice of suture, is probably Reader Poll sphincter toward the anal canal. The the most important factor in achiev- internal anal sphincter is thin and grey- ing a good OASIS repair. However, white in appearance, like a veil. By because many subspecialists favor contrast, the external anal sphincter is PDS suture for sphincter repair, spe- Do you use intrapartum warm a thick band of red striated muscle tis- cialists in obstetrics and gynecology compresses to the perineum sue. In one study of 3,333 primiparous should consider this option. or perineal massage in your women with OASIS, an internal anal practice? sphincter injury was detected in 33% of cases.14 In this large cohort, the rate Can your patient access Tell us at [email protected]. of internal anal sphincter injury with a early secondary repair if 3A tear, a 3B tear, a complete tear of the they develop a perineal Please include your name and city and state. external sphincter and a 4th-degree laceration wound perineal tear was 22%, 23%, 42%, and breakdown? 71%, respectively. The internal anal The breakdown of an OASIS repair is sphincter is important for maintaining an obstetric catastrophe with com- rectal continence and is estimated to plications that can last many months

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Do you use intrapartum warm compresses to the perineum or perineal massage in your practice?

A Cochrane Database Systematic Review reported that positive sensory experience and reinforce her percep- moderate-quality evidence showed a decrease in OASIS tion of the thoughtfulness and caring of her clinicians. with the use of intrapartum warm compresses to the Compared with control, perineal massage was perineum and perineal massage.1 Compared with con- associated with an increase in the rate of an intact trol, intrapartum warm compresses to the perineum perineum (RR, 1.74; 95% CI, 1.11–2.73; 6 studies; did not result in a reduction in first- or second-degree 2,618 women; low-quality evidence; substantial het- tears, suturing of perineal tears, or use of episiotomy. erogeneity among studies) and a decrease in OASIS However, compared with control, intrapartum warm (RR, 0.49; 95% CI, 0.25–0.94; 5 studies; 2,477 women; compresses to the perineum was associated with a moderate quality evidence). Compared with control, reduction in OASIS (relative risk [RR], 0.46; 95% confi- perineal massage did not significantly reduce first- or dence interval [CI], 0.27–0.79; 1,799 women; 4 studies; second-degree tears, perineal tears requiring suturing, moderate quality evidence; substantial heterogeneity or the use of episiotomy (very low-quality evidence). among studies). In addition to a possible reduction in Although perineal massage may have benefit, excessive OASIS, warm compresses also may provide the laboring perineal massage likely can contribute to tissue edema woman, especially those having a natural , a and epithelial trauma.

Reference 1. Aasheim V, Nilsen ABC, Reinar LM, et al. Perineal techniques during the second stage of labour for reducing perineal trauma. Cochrane Database Syst Rev. 2017;CD006672.

and sometimes stretch into years. The follow-up care. One large case series If early secondary repair is selected best approach to a perineal laceration reported on 72 women with complete as the best treatment, 1 to 6 days of wound breakdown remains contro- perineal wound dehiscence who had daily debridement of the wound is versial. It is optimal if all patients with early secondary repair.22 The median needed to prepare the wound for a wound breakdown can be offered time to complete wound healing fol- early secondary repair. The daily an early secondary repair or healing lowing early repair was 28 days. About debridement required to prepare the by secondary intention, permitting 36% of the patients had one or more wound for early repair is often per- the patient to select the best approach complications, including skin dehis- formed in the hospital, potentially for their specific situation. cence, granuloma formation, peri- disrupting early mother-newborn As noted by the pioneers of early neal pain, and sinus formation. A bonding. Following the repair, the repair of episiotomy dehiscence, Drs. pilot randomized trial reported that, patient is observed in the hospital Hankins, Haugh, Gilstrap, Ramin, compared with expectant manage- for 1 to 3 days and then discharged and others,18-20 conventional doc- ment of a wound breakdown, early home with daily wound care and trine is that an episiotomy repair repair resulted in a shorter time to multiple follow-up visits to monitor dehiscence should be managed wound healing.23 wound healing. Pelvic floor physi- expectantly, allowing healing by sec- Early repair of perineal wound cal therapy may be initiated when ondary intention and delaying repair dehiscence often involves a course the wound is healed. The prolonged of the sphincters for a minimum of 3 to of care that extends over multiple process required for early secondary 4 months.21 However, many small weeks. As an example, follow- repair may be best undertaken by a case-series report that early second- ing a vaginal birth with OASIS and subspecialty practice.24 ary repair of a perineal laceration immediate repair, the patient is The surgical repair and postpar- wound breakdown is possible follow- often discharged from the hospital tum care of OASIS continues to evolve. ing multiple days of wound prepara- to home on postpartum day 3. The In your practice you should consider: tion prior to the repair, good surgical wound breakdown often is detected • performing a mediolateral technique and diligent postoperative between postpartum days 6 to 10. episiotomy at a 60-degree angle to

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reduce the risk of OASIS in situa- • using a long-lasting absorbable approximately 112,600 US women tions where there is a high risk of suture, such as PDS, to repair the who experience OASIS each year. ● anal sphincter injury, such as in for- internal and external anal sphincters ceps delivery • ensuring that the patient with a • using one dose of a prophylactic anti- dehiscence following an episi- biotic with extended anaerobic cov- otomy or anal sphincter injury has erage, such as cefotetan or cefoxitin access to early secondary repair. [email protected] • focus on identifying and separately Standardizing your approach to repairing an internal anal sphinc- the prevention and repair of anal Dr. Barbieri reports no financial rela- ter injury sphincter injury will benefit the tionships relevant to this article.

References 1. Friedman AM, Ananth CV, Prendergast E, et al. prophylaxis for prevention of postpartum perineal 17. Williams A, Adams EJ, Tincello DG, et al. How Evaluation of third-degree and fourth-degree lac- wound complications: a randomized controlled to repair an anal sphincter injury after vaginal eration rates as quality indicators. Obstet Gynecol. trial. Obstet Gynecol. 2008;111:1268-1273. delivery: results of a randomised controlled trial. 2015;125:927-937. 10. Harvey MA, Pierce M. Obstetrical anal sphincter BJOG. 2006;113:201-207. 2. Hamilton BE, Martin JA, Osterman MK. Births: injuries (OASIS): prevention, recognition and 18. Hauth JC, Gilstrap LC, Ward SC, et al. Early Provisional data for 2019. Vital Statistics Rapid repair. J Obstet Gynecol Can. 2015;37:1131-1148. repair of an external sphincter ani muscle and Release; No. 8. Hyattsville MD: National Center 11. Cox CK, Bugosh MD, Fenner DE, et al. Antibiotic rectal mucosal dehiscence. Obstet Gynecol. for Health Statistics; May 2020. https://www.cdc. use during repair of obstetrical anal sphincter 1986;67:806-809. gov/nchs/data/vsrr/vsrr-8-508.pdf injury: a qualitative improvement initiative. Int J 19. Hankins GD, Hauth JC, Gilstrap LC, et al. Early 3. Pergialitotis V, Bellos I, Fanaki M, et al. Risk fac- Gynaecol Obstet. 2021; Epub January 28. repair of episiotomy dehiscence. Obstet Gynecol. tors for severe perineal trauma during childbirth: 12. Deierhoi RJ, Dawes LG, Vick C, et al. Choice of 1990;75:48-51. an updated meta-analysis. European J Obstet intravenous antibiotic prophylaxis for colorectal 20. Ramin SR, Ramus RM, Little BB, et al. Early Gynecol Repro Biol. 2020;247:94-100. surgery does matter. J Am Coll Surg. 2013;217:763- repair of episiotomy dehiscence associated with 4. Sultan AH, Kettle C. Diagnosis of perineal trauma. 769. infection. Am J Obstet Gynecol. 1992;167:1104- In: Sultan AH, Thakar R, Fenner DE, eds. Perineal 13. Till Sr, Morgan DM, Bazzi AA, et al. Reducing 1107. and anal sphincter trauma. 1st ed. London, Eng- surgical site infections after hysterectomy: metro- 21. Pritchard JA, MacDonald PC, Gant NF. Williams land: Springer-Verlag; 2009:33-51. nidazole plus cefazolin compared with cephalo- Obstetrics, 17th ed. Norwalk Connecticut: Apple- 5. Jiang H, Qian X, Carroli G, et al. Selective ver- sporin alone. Am J Obstet Gynecol. 2017;217:187. ton-Century-Crofts; 1985:349-350. sus routine use of episiotomy for vaginal birth. e1-e11. 22. Okeahialam NA, Thakar R, Kleprlikova H, et al. Cochrane Database Syst Rev. 2017;CD000081. 14. Pihl S, Blomberg M, Uustal E. Internal anal sphinc- Early re-suturing of dehisced obstetric perineal 6. Coats PM, Chan KK, Wilkins M, et al. A compari- ter injury in the immediate postpartum period: woulds: a 13-year experience. Eur J Obstet Gyne- son between midline and mediolateral episioto- prevalence, risk factors and diagnostic methods in col Repro Biol. 2020;254:69-73. mies. Br J Obstet Gynaecol. 1980;87:408-412. the Swedish perineal laceration registry. European J 23. Dudley L, Kettle C, Thomas PW, et al. Peri- 7. Sooklim R, Thinkhamrop J, Lumbiganon P, et al. Obst Gynecol Repro Biol. 2020;245:1-6. neal resuturing versus expectant management The outcomes of midline versus medio-lateral 15. Fornell EU, Matthiesen L, Sjodahl R, et al. Obstet- following vaginal delivery complicated by a episiotomy. Reprod Health. 2007;4:10. ric anal sphincter injury ten years after: sub- dehisced wound (PREVIEW): a pilot and feasi- 8. El-Din AS, Kamal MM, Amin MA. Comparison jective and objective long-term effects. BJOG. bility randomised controlled trial. BMJ Open. between two incision angles of mediolateral 2005;112:312-316. 2017;7:e012766. episiotomy in primiparous women: a random- 16. Sultan AH, Monga AK, Kumar D, et al. Primary 24. Lewicky-Gaupp C, Leader-Cramer A, Johnson ized controlled trial. J Obstet Gynaecol Res. repair of obstetric anal sphincter rupture using LL, et al. Wound complications after obstet- 2014;40:1877-1882. the overlap technique. Br J Obstet Gynaecol. rical anal sphincter injuries. Obstet Gynecol. 9. Duggal N, Mercado C, Daniels K, et al. Antibiotic 1999;106:318-323. 2015;125:1088-1093.

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