Management of Diarrhea
The cornerstone of diarrhea management is oral rehydration therapy (ORT) using appropriate oral rehydration solutions (ORS), with early resumption of feeding and replacement of ongoing fluid losses. 1, 2
Assessment of Dehydration
- Evaluate the degree of dehydration by examining skin turgor, mucous membranes, mental status, pulse, and capillary refill time 1, 2
- Categorize dehydration as:
- Rapid, deep breathing (acidosis sign), prolonged skin retraction time, and decreased perfusion are reliable predictors of dehydration 1
- Weigh the patient to establish a baseline for monitoring treatment effectiveness 3
Rehydration Strategy Based on Dehydration Severity
Mild Dehydration (3-5% fluid deficit)
- Administer 50 mL/kg of ORS over 2-4 hours 1, 2
- Start with small volumes (e.g., one teaspoon) and gradually increase as tolerated 1
- Reassess hydration status after 2-4 hours 1, 2
Moderate Dehydration (6-9% fluid deficit)
- Administer 100 mL/kg of ORS over 2-4 hours 1
- Use the same administration technique as for mild dehydration 1
- Reassess hydration status after 2-4 hours 1, 2
Severe Dehydration (≥10% fluid deficit)
- This is a medical emergency requiring immediate IV rehydration 1, 2
- Administer boluses (20 mL/kg) of Ringer's lactate solution or normal saline until pulse, perfusion, and mental status normalize 1
- Once consciousness returns to normal, transition to oral rehydration for the remaining deficit 1, 2
Replacement of Ongoing Fluid Losses
- During both rehydration and maintenance phases, replace ongoing fluid losses 1
- Replace each watery stool with 10 mL/kg of ORS 1, 2
- Replace each episode of vomiting with 2 mL/kg of ORS 1, 2
- Continue replacement until diarrhea and vomiting resolve 2
Dietary Management
- Continue breastfeeding throughout the diarrheal episode 1, 2
- Resume age-appropriate diet during or immediately after rehydration 1, 2
- For bottle-fed infants, use full-strength, lactose-free, or lactose-reduced formulas immediately upon rehydration 1
- If lactose-free formulas are unavailable, use full-strength lactose-containing formulas under supervision 1
- Early feeding stimulates intestinal cell renewal and improves outcomes 1
- Avoid the outdated practice of "gut rest" as it can reduce enterocyte renewal and increase intestinal permeability 1
Pharmacological Management
- Antimotility drugs like loperamide are contraindicated in children under 2 years of age due to risks of respiratory depression and cardiac adverse reactions 4
- Loperamide may be used in adults and children over 2 years for symptomatic relief, but should be avoided in cases where inhibition of peristalsis could lead to complications like ileus or megacolon 4
- Ondansetron may be considered for children >4 years with vomiting, but only after adequate hydration is achieved 2
- Zinc supplementation is recommended for children 6 months to 5 years who live in areas with high zinc deficiency or show signs of malnutrition 3, 2
Special Considerations
- Stool cultures are indicated only for bloody diarrhea (dysentery) but are not needed for typical acute watery diarrhea in immunocompetent patients 1
- Patients with high purging rates (>10 mL/kg/hour) can still benefit from ORT with appropriate fluid replacement 1
- True glucose malabsorption (indicated by glucose in stool and dramatic increase in stool output with ORS) occurs in approximately 1% of cases and may require IV therapy 1
- For patients with severe acidosis, a physiological dose of bicarbonate may be needed to correct blood pH to 7.25 5
Follow-up and Monitoring
- Reassess hydration status after the initial rehydration period 1, 2
- If the patient remains dehydrated, reassess the fluid deficit and restart rehydration 3
- Monitor for signs of improvement or deterioration 2
- For chronic diarrhea, refer patients with red flag symptoms (blood in stool, weight loss, anemia, abdominal mass) to gastroenterology 6