Bowel Injury During Caesarean Delivery

Bowel injury during caesarean delivery is a tear, serosal injury, perforation or devascularisation of the small or large bowel during entry into the abdomen or while freeing adhesions. It is more common after repeat surgery. It matters because unrecognised perforation causes peritonitis, abscess and sepsis within 2 to 5 days, with a high mortality.

• Risk factors: multiple previous caesarean sections or abdominal surgery, dense adhesions, previous pelvic infection or endometriosis, emergency surgery, obstructed labour, hernia, obesity.
• The small bowel is injured more often than the colon.
• Careful entry and adhesiolysis reduce the risk.

During surgery the surgeon sees a serosal tear, a hole, faecal soiling or a bowel haematoma. After surgery, women have fever, severe abdominal pain, distension, vomiting, no passage of flatus, tachycardia and a rigid abdomen from day 2 to 5.

• Fever and rising pulse with abdominal distension.
• Pain out of proportion to the wound.
• Differential diagnosis: postcaesarean ileus, endometritis, pelvic abscess, bladder or ureteric injury, wound infection, pulmonary embolism, appendicitis, pancreatitis.
• Complications: peritonitis, intra-abdominal abscess, enterocutaneous fistula, sepsis and septic shock, bowel obstruction, stoma formation, repeat laparotomy, maternal death.

The diagnosis is made at operation by inspection of the bowel, or after surgery by clinical suspicion and imaging.

• Intraoperative: run the bowel for serosal tears, perforation, haematoma and loss of blood supply when adhesions were present; call a general surgeon.
• Postoperative: temperature, pulse, blood pressure, abdominal examination for guarding and distension, bowel sounds.
• Full blood count (rising white cells), C-reactive protein, lactate, urea and electrolytes, blood cultures; erect chest X-ray for free air (may be normal after recent surgery).
• Contrast CT of the abdomen and pelvis for free fluid, free air, collections or contrast leak.

The principle is immediate repair at the time of injury, and early laparotomy and washout when a leak is found later.

• Supportive: resuscitate with two large-bore cannulae and Ringer's lactate 1 litre rapidly then maintenance; nil by mouth with a nasogastric tube on free drainage for ileus or peritonitis; hourly urine output; oxygen; high dependency care; early parenteral nutrition for prolonged ileus; surgeon and anaesthetist involved at once.
• Pharmacological: ceftriaxone 2 g IV once daily plus metronidazole 500 mg IV 8-hourly, continued for 5 to 7 days after source control; meropenem 1 g IV 8-hourly for septic shock or hospital-acquired infection; noradrenaline starting at 0.05 micrograms/kg/minute IV and titrated for mean arterial pressure of 65 mmHg or more; paracetamol 1 g IV 6-hourly (maximum 4 g in 24 hours); morphine 2.5 to 5 mg IV every 4 hours as needed; enoxaparin 40 mg subcutaneous daily for 10 days when stable.
• Procedures: serosal tears closed with interrupted 3/0 silk or polyglactin; small perforations repaired in two layers (3/0 absorbable mucosa, 3/0 silk seromuscular); resection and anastomosis for large or devascularised segments; colonic injuries repaired primarily when clean and early, with a defunctioning colostomy for faecal contamination, delayed diagnosis or instability; peritoneal lavage with 3 to 6 litres of warm sodium chloride 0.9 percent; abdominal drain; planned relaparotomy for ongoing sepsis.
• Red flags: rigid abdomen, fever above 38 degrees Celsius with tachycardia above 110 per minute, vomiting, faecal wound discharge, hypotension, rising lactate above 2 mmol/L, oliguria.
• Follow-up: temperature and abdominal examination 4-hourly; stoma care and closure at 3 to 6 months if a stoma was formed; review at 1 week and 6 weeks; counselling that later births should be planned by an experienced surgeon.