There are four degrees of tears that can occur during delivery:
• First degree tears involve the vaginal mucosa and connective tissue.
• Second degree tears involve the vaginal mucosa, connective tissue and underlying muscles.
• Third degree tears involve complete transection of the anal sphincter.
• Fourth degree tears involve the rectal mucosa.
| Note: It is important that absorbable sutures be used for closure. Polyglycolic sutures are preferred over chromic catgut for their tensile strength, non-allergenic properties and lower probability of infectious complications. Chromic catgut is an acceptable alternative, but is not ideal. |
Most first degree tears close spontaneously without sutures.
• Review general care principles (page C-17).
• Provide emotional support and encouragement. Use local infiltration with lignocaine (page C-38). If necessary, use a pudendal block (page P-3).
• Ask an assistant to massage the uterus and provide fundal pressure.
• Carefully examine the vagina, perineum and cervix (Fig P-46, page P-84).
• If the tear is long and deep through the perineum, inspect to be sure there is no third or fourth degree tear:
- Place a gloved finger in the anus;
- Gently lift the finger and identify the sphincter;
- Feel for the tone or tightness of the sphincter.
• Change to clean, high-level disinfected gloves.
• If the sphincter is injured, see the section on repair of third and fourth degree tears (page P-86).
• If the sphincter is not injured, proceed with repair.
FIGURE P-46 Exposing a perineal tear
• Apply antiseptic solution to the area around the tear (page C-22).
• Make sure there are no known allergies to lignocaine or related drugs.
Note: If more than 40 mL of lignocaine solution will be needed for the repair, add adrenaline to the solution (page C-39).
• Infiltrate beneath the vaginal mucosa, beneath the skin of the perineum and deeply into the perineal muscle using about 10 mL 0.5% lignocaine solution (page C-39).
Note: Aspirate (pull back on the plunger) to be sure that no vessel has been penetrated. If blood is returned in the syringe with aspiration, remove the needle. Recheck the position carefully and try again. Never inject if blood is aspirated. The woman can suffer convulsions and death if IV injection of lignocaine occurs.
• At the conclusion of the set of injections, wait 2 minutes and then pinch the area with forceps. If the woman feels the pinch, wait 2 more minutes and then retest.
| Anaesthetize early to provide sufficient time for effect. |
• Repair the vaginal mucosa using a continuous 2-0 suture (Fig P-47, page P-85):
- Start the repair about 1 cm above the apex (top) of the vaginal tear. Continue the suture to the level of the vaginal opening;
- At the opening of the vagina, bring together the cut edges of the vaginal opening;
- Bring the needle under the vaginal opening and out through the perineal tear and tie.
FIGURE P-47 Repairing the vaginal mucosa
• Repair the perineal muscles using interrupted 2-0 suture (Fig P-48). If the tear is deep, place a second layer of the same stitch to close the space.
FIGURE P-48 Repairing the perineal muscles
• Repair the skin using interrupted (or subcuticular) 2-0 sutures starting at the vaginal opening (Fig P-49, page P-86).
• If the tear was deep, perform a rectal examination. Make sure no stitches are in the rectum.
FIGURE P-49 Repairing the skin
Note: The woman may suffer loss of control over bowel movements and gas if a torn anal sphincter is not repaired correctly. If a tear in the rectum is not repaired, the woman can suffer from infection and rectovaginal fistula (passage of stool through the vagina).
Repair the tear in the operating room.
• Review general care principles (page C-17).
• Provide emotional support and encouragement. Use a pudendal block (page P-3) or ketamine (page P-13). Rarely, if all edges of the tear can be seen, the repair can be done using local infiltration with lignocaine (see above) and pethidine and diazepam IV slowly (do not mix in the same syringe).
• Ask an assistant to massage the uterus and provide fundal pressure.
• Examine the vagina, cervix, perineum and rectum.
• To see if the anal sphincter is torn:
- Place a gloved finger in the anus and lift slightly;
- Identify the sphincter, or lack of it;
- Feel the surface of the rectum and look carefully for a tear.
• Change to clean, high-level disinfected gloves.
• Apply antiseptic solution to the tear and remove any faecal material, if present (page C-22).
• Make sure there are no known allergies to lignocaine or related drugs.
• Infiltrate beneath the vaginal mucosa, beneath the skin of the perineum, and deeply into the perineal muscle using about 10 mL 0.5% lignocaine solution (page C-39).
Note: Aspirate (pull back on the plunger) to be sure that no vessel has been penetrated. If blood is returned in the syringe with aspiration, remove the needle. Recheck the position carefully and try again. Never inject if blood is aspirated. The woman can suffer convulsions and death if IV injection of lignocaine occurs.
• At the conclusion of the set of injections, wait 2 minutes and then pinch the area with forceps. If the woman feels the pinch, wait 2 more minutes and then retest.
| Anaesthetize early to provide sufficient time for effect. |
• Repair the rectum using interrupted 3-0 or 4-0 sutures 0.5 cm apart to bring together the mucosa (Fig P-50).
Remember: Place the suture through the muscularis (not all the way through the mucosa).
- Cover the muscularis layer by bringing together the fascial layer with interrupted sutures;
- Apply antiseptic solution to the area frequently.
FIGURE P-50 Closing the muscle wall of the rectum
• If the sphincter is torn:
- Grasp each end of the sphincter with an Allis clamp (the sphincter retracts when torn). The sphincter is strong and will not tear when pulling with the clamp (Fig P-51, page P-88);
- Repair the sphincter with two or three interrupted stitches of 2-0 suture.
FIGURE P-51 Suturing the anal sphincter
• Apply antiseptic solution to the area again.
• Examine the anus with a gloved finger to ensure the correct repair of the rectum and sphincter. Then change to clean, high-level disinfected gloves.
• Repair the vaginal mucosa, perineal muscles and skin (page P-84).
• If there is a fourth degree tear, give a single dose of prophylactic antibiotics (page C-35):
- ampicillin 500 mg by mouth;
- PLUS metronidazole 400 mg by mouth.
• Follow up closely for signs of wound infection.
• Avoid giving enemas or rectal examinations for 2 weeks.
• Give stool softener by mouth for 1 week, if possible.
A perineal tear is always contaminated with faecal material. If closure is delayed more than 12 hours, infection is inevitable. Delayed primary closure is indicated in such cases.
• For first and second degree tears, leave the wound open.
• For third and fourth degree tears, close the rectal mucosa with some supporting tissue and approximate the fascia of the anal sphincter with 2 or 3 sutures. Close the muscle and vaginal mucosa and the perineal skin 6 days later.
• If a haematoma is observed, open and drain it. If there are no signs of infection and the bleeding has stopped, the wound can be reclosed.
• If there are signs of infection, open and drain the wound. Remove infected sutures and debride the wound:
- If the infection is mild, antibiotics are not required;
- If the infection is severe but does not involve deep tissues, give a combination of antibiotics (page C-35):
- ampicillin 500 mg by mouth four times per day for 5 days;
- PLUS metronidazole 400 mg by mouth three times per day for 5 days.
- If the infection is deep, involves muscles and is causing necrosis (necrotizing fasciitis), give a combination of antibiotics until necrotic tissue has been removed and the woman is fever-free for 48 hours (page C-35):
- penicillin G 2 million units IV every 6 hours;
- PLUS gentamicin 5 mg/kg body weight IV every 24 hours;
- PLUS metronidazole 500 mg IV every 8 hours;
- Once the woman is fever-free for 48 hours, give:
- ampicillin 500 mg by mouth four times per day for 5 days;
- PLUS metronidazole 400 mg by mouth three times per day for 5 days.
Note: Necrotizing fasciitis requires wide surgical debridement. Perform secondary closure in 2–4 weeks (depending on resolution of the infection).
• Faecal incontinence may result from complete sphincter transection. Many women are able to maintain control of defaecation by the use of other perineal muscles. When incontinence persists, reconstructive surgery must be undertaken 3 months or more after delivery.
• Rectovaginal fistula requires reconstructive surgery 3 months or more postpartum.