What is the recommended monitoring schedule and medication dosing for patients with an end ileostomy?

Monitoring and Medication Dosing for End Ileostomy Patients

Patients with end ileostomy require monitoring of fluid output and urine sodium, with fluid intake restricted to <500 mL/day of hypotonic fluids and replacement with glucose-saline solutions containing at least 90 mmol/L sodium, plus loperamide 2-8 mg taken 30 minutes before meals as first-line pharmacologic therapy. 1, 2

Fluid Management Strategy

Hypotonic Fluid Restriction

• Restrict hypotonic oral fluids (water, tea, coffee) to less than 500 mL daily - this is the single most important intervention 1, 2, 3
• Replace all fluid requirements with oral glucose-saline solutions containing at least 90 mmol/L sodium 1, 2, 3
• The modified WHO cholera solution (St. Mark's solution) is recommended: 60 mmol sodium chloride (3.5 g), 30 mmol sodium bicarbonate (2.5 g), and 110 mmol glucose (20 g) in 1 liter tap water 1, 3
• An alternative rehydration solution contains 120 mmol sodium chloride (7 g) and 44 mmol glucose (8 g) in 1 liter tap water 1

Monitoring Parameters for Adequate Hydration

• Target daily urine volume of at least 800 mL 2, 3
• Urinary sodium concentration should be >20 mmol/L 2, 3
• Monitor body weight maintenance 3
• Check serum electrolytes at least daily initially, with particular attention to sodium, potassium, and magnesium 2

Pharmacologic Management

First-Line: Loperamide

• Loperamide 2-8 mg taken 30 minutes before meals (timing before food is critical) 1, 2, 3
• Reduces ileostomy output by approximately 20-30% 1, 4
• Loperamide is preferred over codeine phosphate or other opiates because it is not sedative, not addictive, and does not cause fat malabsorption 1
• High doses (12-24 mg at a time) may be needed in short bowel patients due to disrupted enterohepatic circulation and rapid transit 1, 5
• Guide loperamide use by objective measurements of effect - measure stomal output before and after treatment 1

Second-Line: Antisecretory Agents

For persistent high output (generally >2-3 L/24 hours):

• Proton pump inhibitors (omeprazole 40 mg orally once daily or IV twice daily) or H2 antagonists (ranitidine 300 mg orally twice daily, cimetidine 400 mg orally or IV four times daily) 1, 2
• These reduce stomal output by 1-2 L/24 hours, particularly in patients with net secretory output 1, 2

Third-Line: Octreotide

• Octreotide 50 mcg subcutaneously twice daily for high output jejunostomy/ileostomy when fluid and electrolyte management is problematic despite conventional treatments 1
• Monitor carefully for fluid retention when initiating octreotide, especially in patients with highest stomal outputs 1
• Reduce parenteral support accordingly when octreotide is effective 1
• Consider potential negative interference with intestinal adaptation during long-term use 1

Dietary Modifications

Salt Supplementation

• Add 0.5-1 teaspoon extra salt per day to meals to prevent sodium depletion 2, 6, 3
• Sodium chloride capsules can be used as an alternative to glucose-saline solution 1

Foods That Thicken Output

• Marshmallows, bananas, pasta, rice, white bread, mashed potatoes, and jelly 2, 6
• Small, frequent, nutrient-dense meals/snacks rather than large meals 2, 6

Foods to Avoid

• High-fiber foods increase loose stools, flatulence, and bloating 6
• Fruit and vegetable skins, sweetcorn, celery, and nuts may cause stoma blockages 6

Electrolyte Management

Critical Sequencing Principle

• Correct sodium and water depletion FIRST before addressing other electrolytes 2, 3
• Hypokalemia typically results from secondary hyperaldosteronism due to sodium depletion and resolves once sodium balance is corrected 1, 2, 3
• Potassium supplements are rarely needed once sodium, water balance, and serum magnesium are corrected 3

Hypomagnesemia Management

• Magnesium oxide 4 mmol (160 mg) capsules, total 12-24 mmol daily, given at night when intestinal transit is slowest 1
• If oral magnesium supplements worsen diarrhea or are ineffective, give intravenous magnesium sulfate 4-12 mmol added to saline bags 1
• Alternatively, 1-alpha cholecalciferol can help with magnesium absorption 1

Management of Acute Dehydration

For patients presenting with marked dehydration:

• Begin with intravenous normal saline (2-4 L/day) while keeping patient nil by mouth for 24-48 hours - this stops thirst and the desire to drink 1, 3
• Gradually withdraw IV saline while reintroducing food and restricted oral fluids over 2-3 days 3
• Half to one liter of saline may be given subcutaneously (with 4 mmol magnesium sulfate) if only needed 1-3 times weekly 1

Exclude Reversible Causes

Before attributing high output solely to the ileostomy, systematically exclude:

• Intra-abdominal sepsis or partial/intermittent bowel obstruction 1, 3
• Enteritis (Clostridium, Salmonella) 1, 3
• Recurrent disease in remaining bowel (Crohn's disease, radiation enteritis) 1
• Abrupt stopping of drugs (steroids, opiates) or administration of prokinetics (metoclopramide) 1, 3
• Small bowel bacterial overgrowth in patients with motility disorders or dilated bowel segments 1

Common Pitfalls to Avoid

• Never allow patients to drink large volumes of plain water - this worsens sodium depletion and paradoxically increases stomal output 2
• Do not supplement potassium before correcting sodium and water balance - it is ineffective and unnecessary 2, 3
• Avoid high-fiber "healthy" diets - fiber increases ileostomy output and complications 2
• If tablets/capsules emerge unchanged in stomal output, crush them, open capsules, mix with water, or put on food 1