Day Four After Anterior Resection: Tachycardia, Oliguria and Peri-Anastomotic Gas
A 58-year-old woman is on day 4 after a laparoscopic anterior resection with a stapled colorectal anastomosis 10 cm from the anal verge for a T3 sigmoid adenocarcinoma. She has type 2 diabetes and a BMI of 33. Overnight she develops generalised abdominal pain and feels unwell. Temperature 38.4 °C, heart rate 122/min, blood pressure 104/62 mmHg, respiratory rate 22/min, urine output 15 mL/hour for 4 hours. The abdomen is distended and diffusely tender with guarding, and there has been no flatus since surgery. White cell count 17.8 ×10⁹/L, creatinine 156 µmol/L (pre-operative 78), lactate 3.1 mmol/L, CRP 260 mg/L. A CT scan with intravenous contrast performed urgently shows free fluid with gas bubbles adjacent to the anastomosis, thickening of the anastomotic segment, and no discrete collection. There is no free intraperitoneal gas remote from the anastomosis. The patient is on a surgical ward 40 minutes from the operating theatre.
1. Interpret the clinical and CT findings. What is your working diagnosis and immediate plan for the next two hours, and under what circumstances would you choose a non-operative route instead?
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Interpretation. This is an anastomotic leak until proven otherwise. Small amounts of peri-anastomotic gas can be normal in the first days after colorectal anastomosis, but here they sit alongside free fluid, anastomotic thickening, peritonitis, tachycardia, oliguria, a creatinine doubling and lactate 3.1 mmol/L. The combination of CT appearances and physiological derangement, not the gas alone, drives the decision.
Next two hours.
- Sepsis bundle: cultures, piperacillin–tazobactam (adjusted for renal function), 500 mL crystalloid boluses titrated to urine output and lactate, urinary catheter, hourly observations.
- Nasogastric tube for the distension and vomiting risk; nil by mouth.
- Cross-match, correct potassium, arterial or venous gas, inform critical care, book theatre, consent for laparotomy and stoma, and arrange immediate transfer because she is 40 minutes from theatre.
- Do not send her for CT-guided drainage: there is no collection, and she has generalised peritonitis.
When non-operative management would be reasonable. A contained pelvic collection with an intact anastomosis, no generalised peritonitis and preserved haemodynamics could be treated with percutaneous drainage plus antibiotics, provided the patient is monitored where deterioration can be picked up within minutes. That is not this patient. Waiting for a demarcated collection in someone with peritonitis and rising lactate converts a salvageable leak into a dead patient.
2. At laparotomy you find 800 mL of faecally contaminated fluid, a 1 cm defect at the anastomosis, and viable but oedematous bowel ends with no gross ischaemia. What operation do you perform and why? Discuss the alternatives and what would make you choose them.
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Operation: washout and take-down of the anastomosis with end colostomy (Hartmann procedure).
Reasoning: day 4 means the staple line has essentially no healing strength, the defect is open, the contamination is frankly faecal and the peritoneal cavity is diffusely inflamed. Constructing a new anastomosis in that field has a high risk of a second leak, and a second leak in a patient who has already had one is frequently fatal.
Alternatives and when they apply.
- Washout, drainage and a proximal defunctioning loop ileostomy with the anastomosis left in place: appropriate for a contained, late leak with an intact anastomosis, minimal contamination and a stable patient. It does not deal with an open defect bathed in faeces.
- Suture repair of the defect with proximal diversion: occasionally used for a tiny defect found early with minimal contamination in a stable patient, but it is the highest-risk option here.
- Damage control: if she becomes acidotic, hypothermic or coagulopathic, complete the resection and stoma quickly, leave the abdomen open with a negative-pressure dressing, and plan a second look at 24–48 hours. This is a decision made on physiology, not on peritoneal findings alone.
Send peritoneal fluid for culture, check the rest of the bowel and both ureters, and mark the stoma site preoperatively rather than improvising on the table.
3. Outline the next 72 hours of management, including antibiotics, nutrition and what you tell the family about prognosis and length of stay.
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Immediate postoperative care. Critical care or high-dependency bed, invasive monitoring as needed, hourly urine output, daily bloods including lactate and CRP. Continue broad-spectrum antibiotics and narrow on culture results; 5–7 days after adequate source control is usually sufficient, but this depends on clinical response. Mechanical thromboprophylaxis until bleeding risk settles, then low-molecular-weight heparin.
Nutrition and bowel function. Nasogastric drainage until ileus resolves, then sips of water and build up. Even after take-down with an end colostomy, enteral feeding is usually possible once the ileus settles; reserve parenteral nutrition for prolonged ileus or a complication. Early mobilisation and stoma education from day 1 so that discharge is not delayed by stoma care.
What the family needs to hear. Anastomotic leak after colorectal surgery carries a mortality of roughly 10–20%, higher with faecal peritonitis and organ dysfunction, and she is not out of danger for 48–72 hours. She will have a stoma, likely for 3–6 months, with a planned reversal if she recovers and there is no distant disease. Expect a length of stay of 7–14 days, longer if she needs critical care. Document the conversation, and warn them specifically about the signs of a recurrent collection: fever, pain, falling urine output.