What is the best course of action for a 7-year-old male child experiencing vomiting of digested food, abdominal pain, and subsequent vomiting of liquid secretions, who ate a banana 1 hour after initial vomiting, in a cold weather location?

Management of Acute Gastroenteritis with Persistent Vomiting in a 7-Year-Old Child

Begin immediate oral rehydration therapy using small, frequent volumes of ORS (5-10 mL every 1-2 minutes via spoon or syringe), and consider ondansetron to facilitate oral intake if vomiting prevents adequate rehydration. 1, 2

Immediate Assessment and Classification

Assess dehydration severity immediately using these specific clinical signs: 1, 3

• Mild dehydration (3-5% deficit): Increased thirst, slightly dry mucous membranes 3
• Moderate dehydration (6-9% deficit): Loss of skin turgor with tenting when pinched, dry mucous membranes, decreased urine output 1, 3
• Severe dehydration (≥10% deficit): Severe lethargy or altered consciousness, prolonged skin tenting >2 seconds, cool extremities with poor capillary refill, rapid deep breathing 1, 3

Capillary refill time is the most reliable predictor of dehydration in this age group, more accurate than sunken fontanelle or absent tears. 3

Critical Red Flags Requiring Immediate Medical Attention

Seek emergency care immediately if any of these develop: 1

• Altered mental status (severe lethargy, decreased consciousness, irritability)
• Prolonged skin tenting >2 seconds
• Cool extremities with decreased capillary refill
• Rapid, deep breathing indicating acidosis
• Bloody stools with fever
• Absent bowel sounds on examination
• Persistent vomiting despite proper small-volume ORS technique

Rehydration Protocol Based on Severity

For Mild to Moderate Dehydration (Most Likely Scenario)

The critical mistake parents make is allowing a thirsty, vomiting child to drink large volumes rapidly from a cup or bottle—this perpetuates the vomiting cycle. 2

Correct technique: 1, 2

• Give 5-10 mL of ORS every 1-2 minutes using a teaspoon, syringe, or medicine dropper
• Gradually increase volume as tolerated without triggering vomiting
• For moderate dehydration: Total of 100 mL/kg over 2-4 hours 1, 2
• For mild dehydration: Total of 50 mL/kg over 2-4 hours 2
• Replace each vomiting episode with 2 mL/kg additional ORS 1, 2
• Replace each watery stool with 10 mL/kg additional ORS 1, 2

Ondansetron as Adjunctive Therapy

Consider ondansetron (0.2 mg/kg oral; maximum 4 mg) if vomiting prevents adequate oral intake, as it reduces vomiting, improves ORS tolerance, and reduces need for IV rehydration. 4, 3, 5, 6

• Ondansetron is appropriate for children >4 years with significant vomiting 4
• May increase stool output slightly but improves overall rehydration success 4
• Single oral dose is effective without significant adverse events 6

For Severe Dehydration

If signs of shock or severe dehydration develop: 3, 2

• Immediate IV rehydration with 20 mL/kg boluses of lactated Ringer's or normal saline 3, 2
• This requires emergency medical care—do not attempt home management 1

Nutritional Management

Resume age-appropriate diet immediately upon rehydration—there is no justification for "bowel rest." 1, 3

• Early refeeding reduces severity and duration of illness 1
• Include starches, cereals, yogurt, fruits, and vegetables 3
• Avoid foods high in simple sugars (soft drinks, undiluted apple juice) as they worsen diarrhea through osmotic effects 1, 3
• Avoid high-fat foods and caffeinated beverages during active illness 1

Critical Pitfalls to Avoid

Never give antimotility agents (loperamide) to any child <18 years—they are absolutely contraindicated due to risks of respiratory depression and serious cardiac adverse reactions. 4, 1, 3, 2

Do not use inappropriate fluids like cola, sports drinks, or undiluted juice as primary rehydration solutions—they contain inadequate sodium and excessive osmolarity. 1, 3

Do not give empiric antibiotics for uncomplicated watery diarrhea with vomiting—this is viral gastroenteritis requiring only supportive care. 1, 2

Do not delay rehydration while awaiting diagnostic testing—begin ORS immediately. 1

Monitoring and Reassessment

Reassess hydration status after 2-4 hours by examining: 1, 2

• Skin turgor and mucous membrane moisture
• Mental status and activity level
• Urine output (should resume within 4-6 hours)
• Weight changes if baseline known

When to Seek Medical Care

Return immediately if: 1

• Many watery stools continue despite rehydration
• Vomiting persists despite proper small-volume technique
• Signs of worsening dehydration develop
• Bloody diarrhea appears
• High fever develops
• Stool output exceeds 10 mL/kg/hour
• Child becomes lethargic or difficult to arouse

Infection Control

While managing at home: 1

• Practice rigorous hand hygiene after bathroom use and before food preparation
• Clean and disinfect contaminated surfaces promptly
• Separate ill child from well siblings until at least 2 days after symptom resolution

This successfully rehydrates >90% of children with vomiting and diarrhea without any antiemetic medication when the small-volume, frequent technique is used correctly. 1