What is the role of an enema in the management of ileus?

Role of Enemas in the Management of Ileus

Enemas are primarily indicated for ileus management when there is significant colonic involvement, with lactulose enemas (300 mL lactulose in 700 mL water) specifically recommended for patients with hepatic encephalopathy Grade 3 or 4 and ileus, and vancomycin retention enemas (500 mg in 100 mL normal saline every 6 hours) recommended for fulminant C. difficile infection with ileus. 1, 2

Types of Enemas Used in Ileus Management

Therapeutic Enemas

• Lactulose enemas: Recommended for patients with hepatic encephalopathy (Grade 3 or 4) when oral lactulose needs to be held due to ileus 1

  • Dosage: 300 mL lactulose in 700 mL water for a total of 1 L
  • Goal: Improve mental status while monitoring electrolytes to prevent dehydration and hypernatremia

• Vancomycin retention enemas: Indicated for fulminant C. difficile infection with ileus 1

  • Dosage: 500 mg in approximately 100 mL normal saline per rectum every 6 hours
  • Should be administered together with intravenous metronidazole 500 mg every 8 hours

Decompressive Enemas

• Colonic tube placement after decompressive colonoscopy may be effective in reducing intestinal dilatation in cases of colonic ileus 3

Clinical Context for Enema Use in Ileus

Ileus with Hepatic Encephalopathy

• When oral lactulose cannot be administered due to ileus, rectal administration becomes essential 1
• Particularly important in Grade 3 or 4 hepatic encephalopathy where rapid improvement in mental status is needed

C. difficile Infection with Ileus

• Ileus may impair delivery of orally administered medications to the colon
• Rectal vancomycin ensures direct delivery of the medication to the affected area 1
• Combined with IV metronidazole for systemic coverage

Broader Management Approach for Ileus

Initial Management

1. Identify and treat underlying cause
2. Bowel rest
3. Nasogastric decompression
4. Fluid resuscitation and electrolyte correction 2
5. Consider pharmacological interventions:
   • Metoclopramide for upper GI motility
   • Neostigmine for established colonic ileus not responding to other measures
   • Alvimopan (μ-opioid receptor antagonist) when opioid analgesia is used

Monitoring for Resolution

• Assess abdominal distention
• Monitor bowel sounds
• Track passage of flatus/stool
• Evaluate for complications 2

Cautions and Considerations

• Enemas should be administered with care to avoid perforation, especially in patients with severe inflammation
• Monitor for electrolyte abnormalities, particularly when using lactulose enemas
• In patients with fulminant C. difficile, monitor for systemic absorption of vancomycin, especially with prolonged use and renal failure 1
• Enemas are typically adjunctive therapy and should be used alongside other appropriate interventions for ileus

Special Situations

• For prolonged ileus with bacterial overgrowth, consider antibiotics like rifaximin 2
• In inflammatory bowel disease-related ileus, additional treatments such as corticosteroids may be needed 2
• For mechanical obstruction, surgical intervention may be necessary if there is evidence of perforation, peritonitis, or clinical deterioration despite medical management 4

Enemas represent an important therapeutic option in specific ileus scenarios, particularly when oral medication delivery is compromised or when direct colonic delivery of medications is needed for optimal effect.