How to assess and manage diarrhea in pediatric patients?

Assessment of Loose Bowel Movements in Pediatric Patients

Assess dehydration severity through physical examination focusing on prolonged capillary refill time, abnormal skin turgor, and abnormal respiratory pattern, then initiate oral rehydration solution (ORS) at 50 mL/kg for mild or 100 mL/kg for moderate dehydration over 2-4 hours. 1, 2

Dehydration Severity Classification

Determine the degree of fluid deficit through systematic physical examination:

Mild Dehydration (3-5% fluid deficit): 2

• Increased thirst
• Slightly dry mucous membranes
• Normal to slightly decreased urine output

Moderate Dehydration (6-9% fluid deficit): 1, 2

• Loss of skin turgor (prolonged skin retraction time)
• Dry mucous membranes
• Decreased urine output
• Rapid, deep breathing
• Decreased perfusion

Severe Dehydration (≥10% fluid deficit): 2

• Severe lethargy or altered consciousness
• Prolonged skin tenting
• Minimal to no urine output
• Signs of shock

Most Reliable Clinical Indicators

The three most valid signs for identifying clinically significant dehydration are: 3, 4, 5

• Prolonged capillary refill time
• Abnormal skin turgor (prolonged skinfold retraction)
• Abnormal respiratory pattern (rapid, deep breathing)

Sunken fontanelle and absence of tears are less reliable indicators. 2 Capillary refill time correlates with fluid deficit but can be affected by fever, ambient temperature, and age. 2

Laboratory Assessment

Laboratory testing is not routinely necessary for most cases of acute diarrhea. 5 Consider selective testing in specific situations:

• Low serum bicarbonate combined with clinical parameters may predict dehydration severity 5
• Blood urea nitrogen (BUN) and BUN/creatinine ratio show conflicting correlation with dehydration 5
• Serum sodium and glucose should be checked if hypernatremic dehydration is suspected 6

Treatment Protocol by Severity

Mild Dehydration (3-5% deficit)

Administer ORS containing 50-90 mEq/L sodium at 50 mL/kg over 2-4 hours. 2

Replace ongoing losses: 1

• 10 mL/kg ORS for each diarrheal stool
• 2 mL/kg ORS for each vomiting episode
• For infants <10 kg: 60-120 mL per diarrheal stool or vomiting episode (up to ~500 mL/day)

Age-specific maintenance volumes after initial rehydration: 1

• Children <2 years: 50-100 mL after each loose stool
• Children ≥2 years: 100-200 mL after each loose stool

Moderate Dehydration (6-9% deficit)

Administer ORS at 100 mL/kg over 2-4 hours. 1, 2

ORS tolerance test approach: Start with small volumes (one teaspoon) using a teaspoon, syringe, or medicine dropper, then gradually increase as tolerated. 1 Children who tolerate approximately 25 mL/kg or more during the initial 2-4 hour observation period are more likely to succeed with home oral rehydration. 7

Reassess hydration status after 2-4 hours: 1

• If still dehydrated, reestimate fluid deficit and restart rehydration therapy
• If improved, transition to maintenance therapy with ongoing loss replacement

Alternative for infants unable to drink: Nasogastric tube administration at 15 mL/kg/hour. 1

Severe Dehydration (≥10% deficit)

This constitutes a medical emergency requiring immediate intravenous rehydration with boluses of Ringer's lactate or normal saline. 2

Switch to IV therapy if: 1

• Progression to severe dehydration
• Shock or altered mental status
• Failure of ORS therapy

Dietary Management During Treatment

Breastfed infants: Continue nursing on demand throughout illness. 1, 2

Bottle-fed infants: Administer full-strength, lactose-free, or lactose-reduced formulas immediately upon rehydration. 1, 2

Children >4-6 months: Offer age-appropriate foods every 3-4 hours as tolerated. 1, 2 Resume normal age-appropriate diet as soon as appetite returns—do not "rest the bowel" through fasting. 2

ORS Selection and Administration

Use low-osmolarity ORS for all age groups. 1 Commercial formulations include Pedialyte, CeraLyte, and Enfalac Lytren. 1

Do not use: 2

• Soft drinks (high osmolarity)
• Standard ORS for hypernatremic dehydration (requires specialized management) 6

Monitoring Response to Therapy

Regularly assess: 1

• Skin turgor
• Mucous membrane moisture
• Mental status
• Stool frequency and consistency
• Weight changes throughout therapy

Clinical improvement is usually observed within 48 hours. 8

Medications to Avoid

Loperamide is contraindicated in children <2 years of age due to risks of respiratory depression and serious cardiac adverse reactions. 8 Even in children 2-12 years, use with extreme caution only after consultation, as pediatric patients may be more sensitive to CNS effects and there are rare reports of paralytic ileus. 8

Anti-diarrheal agents are contraindicated for treatment of diarrheal disease in children. 2, 9 The use of antiemetics, antidiarrheals, and spasmolytics is unnecessary and potentially risky. 9

Special Consideration: Hypernatremic Dehydration

If serum sodium is elevated, standard ORS protocols should not be used. 6 Maximum safe rate of sodium decrease is no more than 3 mOsm/kg/H2O per hour. 6 This requires specialized IV fluid management with frequent monitoring every 4-6 hours. 6