What is the treatment for a dilated rectum due to fecal impaction?

Treatment for Dilated Rectum Due to Fecal Impaction

For a dilated rectum due to fecal impaction, the first-line treatment is digital fragmentation of the stool followed by enema administration and implementation of a maintenance bowel regimen to prevent recurrence. 1

Initial Management of Fecal Impaction

Assessment and Confirmation

• Confirm diagnosis through digital rectal examination (DRE) to identify the presence of a large mass of dry, hard stool in the rectum 1
• Note that if impaction occurs in the proximal rectum or sigmoid colon, DRE may be non-diagnostic 1
• Rule out complications such as perforation or bleeding before proceeding with manual disimpaction 1

Distal Fecal Impaction Treatment Algorithm

1. Manual disimpaction:

   • Administer appropriate analgesia and/or anxiolytic before the procedure 1
   • Perform digital fragmentation and extraction of the stool 1

2. Enema administration (after initial disimpaction):

   • Water or oil retention enema to facilitate passage of remaining stool 1
   • Options include:
     • Hypertonic sodium phosphate enema - distends and stimulates rectal motility 1
     • Docusate sodium enema - softens stool by aiding water penetration (takes 5-20 minutes) 1
     • Warm oil retention enema (cottonseed, olive oil) - lubricates and softens stool (hold for at least 30 minutes) 1
     • Bisacodyl enema - promotes intestinal motility 1

3. Oral medication (after partial emptying of distal colon):

   • Administer polyethylene glycol (PEG) orally 1, 2
   • PEG generally produces a bowel movement in 1-3 days 2

Management of Proximal Fecal Impaction

• In the absence of complete bowel obstruction, administer lavage with PEG solutions containing electrolytes to soften or wash out stool 1
• Consider adding other laxatives if needed:
  • Bisacodyl suppository (one rectally daily-BID) 1
  • Lactulose (30-60 mL BID-QID) 1
  • Sorbitol (30 mL every 2 hours x 3, then as needed) 1
  • Magnesium hydroxide (30-60 mL daily-BID) 1
  • Magnesium citrate (8 oz daily) 1

Prevention of Recurrence

• Implement a maintenance bowel regimen immediately after disimpaction 1
• Preferred laxatives include:
  • Osmotic laxatives: PEG, lactulose, magnesium salts 1
  • Stimulant laxatives: senna, cascara, bisacodyl, sodium picosulfate 1
• Avoid bulk laxatives such as psyllium, especially in patients with opioid-induced constipation or limited mobility 1

Special Considerations

For Elderly Patients

• Pay particular attention to assessment of elderly patients who are at higher risk for severe constipation and fecal impaction 1
• Ensure access to toilets, especially for patients with decreased mobility 1
• Provide dietetic support and manage decreased food intake 1
• Optimize toileting: educate patients to attempt defecation at least twice daily, usually 30 minutes after meals 1
• PEG (17 g/day) offers an efficacious and tolerable solution with a good safety profile 1

Severe Cases and Complications

• Monitor for complications of fecal impaction, which include:

  • Urinary tract obstruction
  • Perforation of the colon
  • Dehydration and electrolyte imbalance
  • Renal insufficiency
  • Fecal incontinence
  • Stercoral ulcers and rectal bleeding 1, 3, 4

• In cases of massive fecal impaction leading to megarectum or severe complications, surgical intervention may be necessary 3, 4, 5

Contraindications for Enemas

• Do not use enemas in patients with:
  • Neutropenia or thrombocytopenia
  • Paralytic ileus or intestinal obstruction
  • Recent colorectal or gynecological surgery
  • Recent anal or rectal trauma
  • Severe colitis, inflammation, or infection of the abdomen
  • Toxic megacolon
  • Undiagnosed abdominal pain
  • Recent radiotherapy to the pelvic area 1

Follow-up Care

• After resolution of fecal impaction, conduct colonic evaluation by flexible sigmoidoscopy, colonoscopy, or barium enema 6
• Evaluate underlying causes of constipation and develop a preventive therapy plan 6
• For patients with recurrent fecal impaction, consider methylnaltrexone for opioid-induced constipation (0.15 mg/kg subcutaneous every other day) 1