What are the best practices for managing a fourth-degree (4th) perineal laceration?

From the Guidelines

The best practice for care of a 4th degree vaginal laceration is immediate surgical repair by an experienced provider using a layered closure technique, starting with the rectal mucosa, followed by the internal and external anal sphincter, and finally the perineal body and vaginal mucosa, as recommended by the American Journal of Obstetrics and Gynecology in 2024 1. The repair should be performed using fine absorbable sutures, such as 3-0 or 4-0 polyglactin or poliglecaprone, in a continuous or interrupted fashion. The internal anal sphincter should be approximated with 3-0 delayed absorbable sutures in an end-to-end fashion, while the external anal sphincter can be repaired using either an end-to-end or overlapping technique with 2-0 or 3-0 delayed absorbable sutures. Some key points to consider in the repair and postoperative care of 4th degree lacerations include:

• Using a checklist to ensure adherence to critical care processes, such as that recommended by Schmidt in 2024 1
• Postoperative administration of broad-spectrum antibiotics, such as a second-generation cephalosporin plus metronidazole, for 5-7 days to prevent infection
• Prescribing stool softeners, such as polyethylene glycol 4450 or mineral oil, twice daily for six weeks postpartum to achieve toothpaste consistency stools
• Advising patients to keep the perineal area clean with warm water rinses after toileting, avoid tampons or sexual intercourse for 6 weeks, and perform pelvic floor exercises starting at 6 weeks post-repair
• Managing pain with NSAIDs and acetaminophen, reserving opioids for breakthrough pain
• Scheduling close follow-up at 2 and 6 weeks to assess healing and function, with referral to pelvic floor physical therapy if symptoms of fecal or urinary incontinence persist, as recommended by the American Journal of Obstetrics and Gynecology in 2024 1.

From the Research

Best Practices for Care of 4th Degree Vaginal Laceration

• Postdelivery care should focus on controlling pain, preventing constipation, and monitoring for urinary retention 2
• Acetaminophen and nonsteroidal anti-inflammatory drugs should be administered as needed, while opiates should be avoided to decrease the risk of constipation 2
• Osmotic laxative use can lead to earlier bowel movements and less pain during the first bowel movement 2
• Daily cleaning of the area under running water is recommended, particularly after bowel movements, and may be carried out either by rinsing or alternate cold and warm water douches 3
• Therapy should also include the postoperative use of laxatives over a period of at least 2 weeks 3

Surgical Repair

• Lacerations involving the anal sphincter complex require additional expertise, exposure, and lighting, and transfer to an operating room should be considered 2
• The surgeon must use the method with which he/she is most familiar for the management of tears of the external anal sphincter, as neither the end-to-end technique nor the overlapping technique have been found to offer better results 3
• Creation of a bowel stoma during primary management of a perineal tear is not indicated 3

Antibiotic Prophylaxis

• Prophylactic antibiotics may have a role in preventing perineal wound infection in third- and fourth-degree perineal tears 4
• One study found that prophylactic antibiotics reduced perineal wound complications at the two-week postpartum check-up 4
• However, the use of antibiotics for 3rd and 4th degree vaginal lacerations is not consistent, and further research is needed to characterize best practices 5

Follow-up Care

• The patient must be informed about the impact of the injury on subsequent births as well as the possibility of anal incontinence 3
• Vaginal and anorectal palpation is essential to assess the extent of birth trauma, and a careful inspection and/or palpation by the obstetrician and/or the midwife must be carried out to exclude a 3rd or 4th degree perineal tear after every vaginal birth 3