What is the best course of treatment for a patient with gangrenous bowel post Extracorporeal Membrane Oxygenation (ECMO)?

Management of Gangrenous Bowel Post-ECMO

Immediate surgical resection of gangrenous bowel is mandatory, with the surgical approach (limited resection vs. damage control) determined by hemodynamic stability and extent of ischemia. 1

Immediate Surgical Intervention Required

• Gangrenous bowel demands urgent surgical exploration without delay, as mortality increases significantly with any postponement of intervention 2
• Post-ECMO patients with gangrenous bowel represent a surgical emergency requiring immediate laparotomy, as these patients already have compromised hemodynamics and cannot tolerate further deterioration 3, 4
• The presence of gangrene indicates transmural necrosis and mandates resection rather than observation, as conservative management is futile and lethal 4

Surgical Approach Based on Patient Stability

Hemodynamically Stable Patients

• Perform limited intestinal resection with primary anastomosis if the gangrenous segment is clearly demarcated and the patient maintains stable hemodynamics 1
• Assess intestinal viability carefully at the resection margins before creating anastomosis 1
• Consider using indocyanine green (ICG) fluorescence angiography to evaluate bowel perfusion and anastomotic viability if available, as this technology has proven particularly valuable in ECMO patients with compromised perfusion 1, 5

Hemodynamically Unstable Patients

• Implement damage control surgery with open abdomen approach in patients with extensive intestinal ischemia, peritonitis, or hemodynamic instability 1
• Resect only obviously gangrenous bowel, create ostomies rather than anastomoses, and plan for re-exploration 1
• Avoid primary anastomosis in unstable patients, as anastomotic leak in this population is nearly universally fatal 1

Critical Intraoperative Considerations

• Systematically inspect the entire small bowel from ileocecal junction proximally to identify all areas of ischemia, as skip lesions are common in low-flow states 1
• Post-ECMO patients have unique perfusion patterns due to altered hemodynamics and low pulsatility, making visual assessment of viability unreliable without adjunctive technology 5
• ICG fluorescence angiography provides real-time objective assessment of mesenteric perfusion in ECMO patients where traditional clinical indicators (color, peristalsis, pulsation) are unreliable 5

Resection Strategy

• Resect all gangrenous bowel with adequate margins of viable tissue (typically 10-20 cm beyond grossly affected areas when perfusion allows) 4
• In cases of extensive gangrene involving multiple segments or the majority of small bowel, consider whether resection is compatible with survival before proceeding 2
• Patients over 84 years with extensive gangrene have extremely poor outcomes (93% mortality), which should inform surgical decision-making and family discussions 2

Post-ECMO Specific Complications

• Ischemic colitis occurs in ECMO patients due to splanchnic hypoperfusion from altered flow dynamics and systemic inflammation 3
• The combination of cardiogenic shock and mesenteric ischemia carries exceptionally high mortality, making aggressive early intervention critical 5
• Post-ECMO bowel ischemia represents both occlusive (thrombotic) and non-occlusive (low-flow) mechanisms, often simultaneously 6, 4

Critical Pitfalls to Avoid

• Never delay surgery for additional imaging or optimization attempts once gangrenous bowel is suspected clinically—every hour of delay increases mortality 2
• Do not rely on traditional visual assessment of bowel viability in post-ECMO patients, as low pulsatility and altered perfusion make clinical judgment unreliable 5
• Avoid creating anastomoses in the presence of ongoing hemodynamic instability, acidosis, or coagulopathy—damage control with ostomies is safer 1
• Do not underestimate the extent of ischemia; when in doubt, resect more rather than less, as leaving marginally viable bowel leads to subsequent perforation 4

Postoperative Management

• Plan for re-exploration within 24-48 hours if damage control surgery was performed, to reassess bowel viability and definitively manage the abdomen 1
• Maintain aggressive hemodynamic support and correct coagulopathy, as these patients remain at high risk for ongoing ischemia 3, 4
• Monitor for anastomotic complications if primary anastomosis was performed, with low threshold for re-exploration given the high-risk nature of this population 1