What is the management of ischemic colitis?

Management of Ischemic Colitis

Most patients with ischemic colitis require only supportive medical management with bowel rest, intravenous fluids, and broad-spectrum antibiotics, but those with peritoneal signs, hemodynamic instability, or isolated right colon involvement require urgent surgical consultation and possible resection. 1, 2

Initial Assessment and Risk Stratification

The first critical step is distinguishing gangrenous from nongangrenous ischemic colitis, as this determines whether medical or surgical management is appropriate 2:

• Obtain CT abdomen/pelvis with IV and oral contrast to assess bowel wall thickening, pneumatosis, portal venous gas, or lack of bowel wall enhancement—findings that suggest transmural necrosis 1
• Check laboratory markers including CBC (leukocytosis), lactate (elevated suggests necrosis), and metabolic panel 1
• Perform colonoscopy in hemodynamically stable patients without peritonitis to confirm diagnosis and assess severity; this is the reference standard for diagnosis 1, 3
• Identify the distribution of disease: isolated right colon ischemia carries significantly worse prognosis with higher mortality and surgical rates compared to left-sided disease 1, 4

Medical Management (Nongangrenous Disease)

For patients without peritoneal signs or evidence of transmural necrosis, conservative management is appropriate 3, 5:

• Bowel rest with NPO status and nasogastric decompression if needed 6, 1
• Intravenous fluid resuscitation to correct hypovolemia and optimize perfusion 6, 1
• Broad-spectrum antibiotics covering gram-negative and anaerobic organisms, though evidence is limited, this is standard practice to prevent bacterial translocation 1, 2
• Discontinue vasoconstrictive medications and address underlying precipitating factors (hypotension, cardiac arrhythmias, medications) 1, 3
• Serial abdominal examinations every 4-6 hours to detect clinical deterioration 6
• Monitor vital signs closely with continuous assessment for development of peritonitis 6

Approximately 85% of nongangrenous cases resolve with supportive care alone within 24-48 hours 3, 5.

Surgical Management (Gangrenous Disease)

Immediate surgical consultation and intervention are mandatory for the following 1, 4, 2:

• Peritoneal signs (rebound tenderness, guarding, rigidity) 1, 2
• Hemodynamic instability despite adequate resuscitation 4, 2
• CT findings of pneumatosis intestinalis, portal venous gas, or free intraperitoneal air 6, 1
• Isolated right colon ischemia due to high risk of concurrent acute mesenteric ischemia and transmural necrosis 1, 4
• Pancolonic involvement which carries worse prognosis 4
• Failure of medical management after 24-48 hours 2

Surgical Approach

• Resection of necrotic bowel is the primary surgical intervention 4, 2
• Damage control surgery with temporary abdominal closure should be considered in critically ill patients, allowing for second-look laparotomy at 24-48 hours to reassess bowel viability 6
• Primary anastomosis versus stoma creation: in the setting of gangrenous ischemia with peritonitis or hemodynamic instability, stoma creation (ileostomy or colostomy) is safer than primary anastomosis 4
• Second-look laparotomy at 24-48 hours is mandatory after extensive bowel involvement to avoid resecting potentially viable bowel 6

Special Considerations

Nonocclusive Mesenteric Ischemia (NOMI)

If NOMI is the underlying cause 6:

• Correct the precipitating cause: optimize cardiac output, eliminate vasopressors if possible 6
• Consider catheter-directed papaverine infusion (0.5-1 mg/kg/min) into the superior mesenteric artery, which has shown mortality reduction from 97% to 66% in retrospective studies 6
• Systemic anticoagulation with heparin may be considered in low-flow states 6
• Surgical exploration remains necessary if peritoneal signs develop 6

Evaluation of Mesenteric Vasculature

• In isolated right colon ischemia, evaluate mesenteric vessels with CT angiography to exclude acute mesenteric ischemia from superior mesenteric artery occlusion 1
• Consider thrombophilia workup in young patients (<50 years) or those with recurrent ischemia, but this is not universally required 1

Common Pitfalls

• Delaying surgical consultation in right-sided ischemia: this distribution has 21% surgical rate and higher mortality; early surgical involvement is critical 1, 4
• Missing the diagnosis in patients without bloody diarrhea: nearly 50% of patients don't present with the classic triad of abdominal pain, urgency, and bloody diarrhea 1
• Performing colonoscopy in patients with peritonitis: this risks perforation and should be avoided 1
• Attributing symptoms to inflammatory bowel disease without excluding ischemia: always consider ischemia in elderly patients or those with cardiovascular risk factors presenting with colitis 7

Monitoring and Follow-up

For patients managed medically 3, 2:

• Repeat colonoscopy at 2-4 weeks if symptoms persist to assess for chronic sequelae (stricture, persistent segmental colitis) 5, 2
• 10-15% of nongangrenous cases develop chronic complications requiring eventual surgery 5
• Mortality for nongangrenous disease is <5%, whereas gangrenous ischemic colitis carries 50-85% mortality even with surgical intervention 6, 5