Postpartum Traumatic Rectal Tear After Normal Vaginal Delivery with an Intact Anal Sphincter

Introduction

Perineal trauma of varying severity often occurs during vaginal delivery, and scrupulous examination of the area should always be performed to exclude occult lacerations. A rare case of a “buttonhole” perineal laceration, reportedly caused after sexual intercourse during early postpartum period, is reported.

Case

A-25-year-old gravida 1, para 1, who had had a normal vaginal labor 27 days earlier at another hospital, was admitted to the Alexandra Obstetrics and Gynecology University Hospital of Athens, Greece. She complained about a sudden onset of pain in the genital area and excessive genital bleeding after sexual intercourse a few hours earlier.

During gynecologic examination, no episiotomy scar was noted, and according to her medical history, she had given birth to a vertex-presenting newborn weighing 3600 g. After examination with a speculum, a mild vaginal hemorrhage was noted but no signs of trauma to the cervix, the vagina wall, or the fornices were noted. However, after digital rectal examination, a midline trauma involving both the rectum and the posterior vaginal wall was revealed. The size of the laceration was ∼4 cm long. The anal sphincter itself was intact. No fecal contamination was noted at the vaginal walls and the patient mentioned having normal postpartum voiding, the most recent being on the day of admission, with no anal incontinence. In addition, she reported normal lochia during the postpartum period. Notably, no postnatal visits had been scheduled and no gynecologic examination had been performed after her discharge date.

Her blood pressure was 90/50 mm Hg, her heart rate was 95 beats per minute, and her body temperature was 37.2°C. Complete blood count and other laboratory tests were performed and the results of these tests were evaluated. Her hemoglobin was 10 g/dL, her white blood cell count was 9600/mm³ (74.1% neutrophils), and her platelet count was 348 K/μL. Results of the rest of the ordered workup were normal.

A decision to perform immediate surgery was made, and the patient was admitted to the hospital's operating room a few hours later. With the patient under general anesthesia, the traumatized surfaces of the vagina were cleaned thoroughly with normal saline and povidone–iodine solution. The trauma evaluation and the operation were performed by S.A. (the first author of this article), who is a specialist in urogynecology and has extensive experience in pelvic-floor surgery.

To reveal the rectal mucosal membrane's upper margins fully, the rectum was detached from the adjacent organs. Afterward, single sutures, using an absorbable multifilament 3.0 suture thread composed of synthetic polyglycolic acid, were used along the vaginal route to repair the rectal mucosa. The rectal muscularis layer was sutured with single PDS 2.0 sutures. The rectovaginal septum was repaired with vertical mattress PDS 2.0 sutures. Finally, for the vaginal wall, a continuous, unlocked, PDS 2.0 suture was used. No colostomy was performed and no colorectal surgeons were involved. The patient was prescribed antibiotics (second-generation cephalosporin for 14 days and metronidazole for 5 days) and laxatives (lactulose). She was put on a hydric (low fiber/high fluid) diet for 1 week, followed by a low-residue diet for the rest of the month. She was discharged on day 10 postoperatively after having defecated and been evaluated by a general surgeon.

Discharge notes included laxatives and instructions to avoid sexual intercourse for 2 months. The patient was advised to return to the hospital after 1 month for a follow-up visit.

Results

The postoperative period was uneventful, as confirmed by telephone contact. The patient returned for the scheduled appointment and physical examination was negative for any fistula formation or surgical injuries.

Discussion

Perineal trauma laceration classification does not define explicitly isolated rectal, or rectal and vaginal, with intact anal sphincter, (buttonhole) injuries. A classification system proposed by Sultan defined perineal laceration as: first degree, for lacerations of the vaginal epithelium or perineal skin only; second degree, when perineal muscles but not the anal sphincter are involved; and third degree, when there is disruption of the anal sphincter muscles. This last category was subdivided further into: 3a when <50% thickness of the external sphincter is torn; 3b when >50% thickness of the external sphincter is torn; and 3c when the internal sphincter is completely torn. Finally, fourth degree laceration, according to Sultan, was a third-degree tear with disruption of the anal epithelium. ¹ It is, essential, however, to consider the “buttonhole” type of trauma as one of great severity and to manage it accordingly. This is because of the existence of a rectal laceration.

Published references regarding this type of case are scarce. In one report, particularly, published by Thirumagal and Bakour, a similar kind of trauma happened during normal vaginal delivery. ² The authors failed to relate this trauma to any predisposing factors, such as operative or prolonged delivery, increased newborn birth weight, or previous labor episiotomy scars or lacerations, and attributed the occurrence of this type of injury to a possible congenital rectovaginal-septum defect.

In the present case, the history suggests an obvious factor (i.e., sexual intercourse). Temporal proximity to the labor, however, raises the suspicion of an occult, minor-degree trauma misdiagnosed during the short inpatient postpartum period. The value of detailed examination of the vaginal walls and rectal digital examination immediately after labor cannot be overemphasized here. In the present case, the patient remained asymptomatic in the early postpartum period probably because adjacent edematous tissues caused a temporary occlusion of the defect, masking the symptoms of a rectovaginal communication. Resumption of sexual activity revealed a trauma that had existed since delivery, and which had not healed adequately. Alternatively, a smaller asymptomatic rectovaginal laceration might have been enlarged by resumption of sexual intercourse.

Regarding severe (and “buttonhole”) perineal inuries, not much emphasis has been placed on whether, in order to achieve the optimum result, third- and fourth-degree perineal lacerations should be repaired by obstetricians or colorectal surgeons. Although it has been suggested that colorectal surgeons' involvement could lead to superior results, ³ in other studies, no benefit was proven. ⁴ Even among colorectal surgeons (in a study among U.K. practitioners), practice in acute sphincter repair is far below adequate; 60% of these surgeons had not performed a single one in the previous year. ⁵ It is logical to assume that the most experienced surgeon available (regardless whether that surgeon is an obstetrician or colorectal surgeon) should perform the operation. However, lack of proper training and education is evident in all levels of obstetricians, residents, and midwives.^5,6 This highlights the need for better education through courses and hands-on practice among obstetricians.

In terms of determining the best surgical approach in “buttonhole” injuries, Sultan proposes that the repair should be done transvaginally. ⁷ It is suggested that repair of the rectum be performed using interrupted Vicryl sutures. In order to minimize the risk of rectovaginal fistula formation, rectovaginal fascia should be interposed as a second layer. Colostomy is generally not recommended unless large tears (extending above the pelvic floor) exist or there is fecal contamination of the wound. ⁷ In this case, layer-by-layer repair was performed. For the rectal musosa, synthetic polyglycolic acid polymer suture was used. The rectal muscularis layer, rectovaginal fascia, and vaginal wall were repaired with polydioxanone suturing. Broad-spectrum antibiotics and stool softeners should be prescribed, and sexual intercourse should be avoided until healing is complete.

With respect to time of intervention, late (up to 12 hours) repair does not seem to produce an inferior functional result 1 year after surgery, ⁸ although immediate surgery's main advantages are emotional comfort of the woman in this important moment of her life, control of possible active bleeding, and avoidance of tissue edema and infection. ⁷

Conclusions

“Buttonhole” perineal injuries are rare, and, therefore, not many data exist on the best medical approach. Medicolegal aspects of the issue are present, and, therefore, good knowledge of perineal anatomy is mandatory before attempting repair of the injury. Experienced obstetricians or colorectal surgeons should be involved. Proper surgical techniques and layer-by-layer restoration of the anatomical region should be performed in order to avoid serious sequlae such as rectovaginal fistulae. Evidence of lack of adequate training among health practitioners involved in such situations is alarming, and highlights the need for more efforts to be made in this field.