What's the next step for a 98-year-old patient with constipation who hasn't had a bowel movement (BM) after taking two stool softeners and a suppository?

Management of Constipation in a 98-Year-Old Patient

For a 98-year-old patient with constipation who hasn't responded to two stool softeners and a suppository, you should perform manual disimpaction following pre-medication with an analgesic and anxiolytic, then administer a tap water enema until clear. 1

Initial Assessment

First, rule out serious causes of constipation:

• Check for fecal impaction through digital rectal examination
• Assess for bowel obstruction (physical exam, consider abdominal x-ray)
• Review medications that may cause constipation
• Rule out metabolic causes (hypercalcemia, hypokalemia, hypothyroidism, diabetes)

Treatment Algorithm

Step 1: Address Potential Impaction

• The patient has already tried stool softeners and suppositories without success, suggesting possible impaction
• Pre-medicate with analgesic and anxiolytic to reduce discomfort
• Perform manual disimpaction if impaction is found 1

Step 2: Administer More Aggressive Laxative Therapy

• Administer tap water enema until clear 1
• Consider adding stronger laxatives:
  • Bisacodyl suppository (one rectally daily to twice daily) 1, 2
  • Polyethylene glycol (1 capful/8 oz water twice daily) - first-line treatment 1, 2
  • Lactulose (30-60 mL 2-4 times daily) 1
  • Magnesium citrate (8 oz daily) - use with caution in elderly due to potential renal issues 1, 2

Step 3: Consider Special Interventions for Refractory Constipation

• If opioid-induced constipation is suspected, consider methylnaltrexone 0.15 mg/kg subcutaneously every other day (except in cases of post-op ileus or mechanical bowel obstruction) 1, 2
• Consider adding a prokinetic agent such as metoclopramide (10-20 mg orally four times daily) if gastroparesis is suspected 1

Important Considerations for Elderly Patients

• Fluid intake: Ensure adequate hydration, as dehydration is common in the elderly and worsens constipation 2
• Medication review: Discontinue any non-essential constipating medications 1, 2
• Avoid long-term use: Do not use stimulant laxatives like bisacodyl or senna for more than one week without medical supervision 3, 4
• Caution with magnesium products: Use with caution in elderly patients due to potential renal impairment 2, 5

Ongoing Management

• Set a goal of one non-forced bowel movement every 1-2 days 1
• Reassess for cause and severity of constipation if initial interventions fail 1
• Consider combination therapy for refractory cases 2
• Avoid bulk-forming laxatives like psyllium for opioid-induced constipation 2

Common Pitfalls to Avoid

• Relying solely on stool softeners (like docusate) - evidence shows they may not be effective when used alone 1, 6
• Using bulk laxatives without ensuring adequate fluid intake 2
• Overlooking fecal impaction as a cause of persistent constipation 7
• Continuing ineffective treatments without escalating to more aggressive interventions 8

In this advanced age group, prompt and effective management of constipation is essential to prevent complications and maintain quality of life. The National Comprehensive Cancer Network guidelines provide a clear stepwise approach that is applicable to elderly patients with constipation, regardless of cancer status.