What is the treatment for ischemic colitis?

Treatment of Ischemic Colitis

Most patients with ischemic colitis respond to conservative medical management including bowel rest, IV fluid resuscitation, correction of electrolytes and anemia, thromboprophylaxis, and broad-spectrum antibiotics, with surgical intervention reserved for those with peritoneal signs, hemodynamic instability, or transmural necrosis. 1, 2

Initial Assessment and Stabilization

Immediate resuscitation and risk stratification are critical:

• NPO status with bowel rest and nasogastric decompression if ileus or distension is present 2
• Aggressive IV fluid resuscitation to correct hypovolemia and optimize colonic perfusion 2
• Correct electrolyte abnormalities (particularly potassium >60 mmol/day) and maintain hemoglobin >8-10 g/dL with transfusion if needed 1
• Subcutaneous low-molecular-weight heparin for thromboprophylaxis, as thromboembolism risk is elevated 1
• Discontinue all vasoconstrictive medications including NSAIDs, vasopressors (when possible), cocaine, and ergots 1

Medical Management (Non-Gangrenous Disease)

Conservative treatment is successful in approximately 80% of cases:

• Broad-spectrum antibiotics should be initiated empirically, though controlled trials have not shown consistent benefit in acute colitis, antibiotics are standard practice for ischemic colitis 3, 4
• Serial abdominal examinations every 4-6 hours to detect clinical deterioration with continuous vital sign monitoring 2
• Daily laboratory monitoring including CBC, electrolytes, lactate, and inflammatory markers 1
• Nutritional support with enteral nutrition preferred over parenteral (9% vs 35% complication rate) if the patient is malnourished 5

Important caveat: Mortality for non-gangrenous disease is <5%, but delays in recognizing progression to gangrenous disease dramatically increase mortality to 50-85% 2

Surgical Indications (Gangrenous Disease)

Immediate surgical consultation and intervention are required for:

• Peritoneal signs including rebound tenderness, guarding, or rigidity 2
• Hemodynamic instability with persistent hypotension or shock despite resuscitation 1
• CT findings of transmural necrosis: pneumatosis intestinalis, portal venous gas, free intraperitoneal air, or lack of bowel wall enhancement 2
• Lactic acidosis suggesting transmural ischemia and bowel necrosis 1
• Failure of conservative management after 24-48 hours with worsening clinical status 3

Surgical approach consists of:

• Extended resection of all nonviable bowel without primary anastomosis 1
• Consider "second look" laparotomy 24-48 hours later to reassess bowel viability 1
• Prophylactic cholecystectomy may be considered during the initial operation 6

Special Populations and Contexts

Isolated right colon ischemia requires heightened vigilance:

• This pattern is associated with more severe outcomes, higher surgical rates, and increased mortality 4
• Evaluation of mesenteric vasculature is essential to exclude concurrent acute mesenteric ischemia 4
• Lower threshold for surgical consultation given worse prognosis 4

Nonocclusive mesenteric ischemia (NOMI):

• Correct the precipitating cause: optimize cardiac output, eliminate vasopressors when possible 2
• Consider catheter-directed papaverine infusion into the superior mesenteric artery 2

Monitoring Strategy

Joint medical-surgical management with:

• Daily physical examination to evaluate for abdominal tenderness and peritoneal signs 1
• Vital signs monitoring four times daily or more frequently if deterioration noted 5
• Stool chart documenting frequency, character, and presence of blood 5
• Serial imaging with plain abdominal radiographs if colonic dilatation (transverse colon >5.5 cm) detected, or low threshold for repeat CT if clinical deterioration 5, 2

Critical Pitfalls to Avoid

• Do not delay diagnosis with prolonged observation in patients with abdominal pain out of proportion to examination findings—this suggests mesenteric ischemia requiring urgent intervention 1
• Do not use anticholinergics, antidiarrheals, or opioids as these may precipitate toxic dilatation 5
• Do not continue vasoconstrictive agents when ischemic colitis is suspected 1
• Do not perform colonoscopy in patients with peritoneal signs or suspected perforation 3