Day 3 critical care after Hartmann's procedure: vasoplegia, fluid overload and abdominal hypertension
A 71-year-old man is in the intensive care unit on day 3 after emergency laparotomy and Hartmann's procedure for perforated sigmoid diverticulitis with faecal peritonitis. He remains ventilated and sedated. Norepinephrine is running at 0.35 µg/kg/min to maintain a mean arterial pressure of 66 mmHg; pulse is 112/min in sinus rhythm, central venous pressure 16 mmHg, and mixed venous oxygen saturation 78%. Over the past 4 hours urine output has been 15–20 mL/h despite 2 L of crystalloid. Bloods: haemoglobin 74 g/L, platelets 86 × 10⁹/L, creatinine 224 µmol/L (baseline 88), lactate 4.4 mmol/L rising from 2.6, bilirubin 28 µmol/L, international normalised ratio 1.6. Bladder pressure is 19 mmHg. Bedside ultrasound shows a non-collapsing inferior vena cava of 2.4 cm, bilateral B-lines, and a left ventricular ejection fraction of 55% with no pericardial effusion. The abdomen is tense, the laparostomy wound is clean but the stoma is dusky.
1. Interpret his haemodynamic and organ function data. Is he fluid-depleted or fluid-overloaded? Justify your answer.
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He is fluid-overloaded and vasoplegic, not hypovolaemic.
The central venous pressure of 16 mmHg, non-collapsing inferior vena cava of 2.4 cm and bilateral B-lines indicate high right- and left-sided filling pressures with extravascular lung water. Mixed venous oxygen saturation of 78% does not support a low cardiac output state, and the ejection fraction of 55% argues against primary pump failure, although diastolic dysfunction may coexist. The high norepinephrine requirement indicates vasodilation, typical of sepsis.
The oliguria is best explained by renal perfusion pressure, not volume depletion. With a mean arterial pressure of 66 mmHg and intra-abdominal pressure of 19 mmHg, renal perfusion pressure is only about 47 mmHg, below the autoregulatory range. The rising lactate and creatinine fit abdominal compartment syndrome with superimposed septic source, rather than dehydration. The tense abdomen, dusky stoma and platelet fall add to this. More fluid would raise filling pressures and intra-abdominal pressure further and worsen renal and respiratory function.
2. What is the differential diagnosis for his rising lactate and oliguria, and which is most likely?
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The differential includes:
- Abdominal compartment syndrome: intra-abdominal pressure 19 mmHg with new organ dysfunction, tense abdomen and oliguria. Most likely.
- Uncontrolled intra-abdominal sepsis: anastomotic or rectal stump leak, ischaemic bowel or a collection. Also likely and may coexist.
- Hypovolaemia: possible from third-space loss or bleeding, but filling pressures and ultrasound make it unlikely.
- Cardiogenic failure: ejection fraction is preserved, but diastolic dysfunction or sepsis-related myocardial depression cannot be excluded.
- Adrenal insufficiency: consider if vasopressor requirement is refractory.
- Mesenteric ischaemia: the dusky stoma and lactate rise are warning signs.
The combination of intra-abdominal pressure, oliguria, rising lactate and a tense abdomen makes abdominal compartment syndrome the leading diagnosis, with a septic source needing exclusion. Lactate is not a perfusion marker alone; it also reflects sepsis, hepatic dysfunction and impaired clearance.
3. Set out your management priorities for the next 6 hours, including fluid, transfusion, renal support and abdominal pressure. Which single intervention is most likely to improve renal perfusion?
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Abdominal decompression is the single intervention most likely to improve renal perfusion. Reducing intra-abdominal pressure from 19 mmHg toward below 12 mmHg raises renal perfusion pressure without further fluid loading. In an open abdomen, I would check that the temporary closure is not under tension, consider releasing fascial sutures or a mesh, place a nasogastric tube, use neuromuscular blockade and consider percutaneous drainage of any collection.
Other priorities:
- Fluid: stop resuscitation. Use furosemide only if there is a diuretic response, or start continuous renal replacement therapy for fluid removal and to control creatinine and acidosis.
- Source control: arrange CT or return to theatre if there is suspicion of a leak or ischaemic bowel; do not delay for a scan if the abdomen is worsening.
- Vasopressors: titrate norepinephrine to a mean arterial pressure of 65–70 mmHg; consider vasopressin if requirements escalate.
- Transfusion: haemoglobin 74 g/L with ischaemia and sepsis supports transfusion to about 80 g/L. Platelets 86 × 10⁹/L do not require transfusion without bleeding. Do not give fresh frozen plasma for an INR of 1.6 alone.
- Monitoring: measure intra-abdominal pressure regularly, monitor urine output and lactate, and reassess fluid status with ultrasound.