What is the approach to managing persistent vomiting in a pediatric patient?

Approach to Persistent Vomiting in a 10-Year-Old Girl

Begin by immediately assessing for bilious (green-colored) vomiting, which indicates intestinal obstruction or malrotation with volvulus and requires emergency surgical consultation. 1, 2

Initial Assessment: Red Flag Signs

Evaluate for the following critical warning signs that require immediate intervention:

• Bilious or bloody vomiting – suggests intestinal obstruction, malrotation with volvulus, or other surgical emergencies 1, 2, 3
• Severe dehydration (≥10% fluid deficit) – characterized by prolonged skin tenting >2 seconds, cool extremities, decreased capillary refill, rapid deep breathing, and altered mental status 1, 4
• Altered sensorium or papilledema – indicates increased intracranial pressure or central nervous system pathology 3, 5
• Abdominal distension or tenderness – suggests obstruction, appendicitis, or other acute abdominal pathology 2, 3
• Toxic/septic appearance – may indicate systemic infection, diabetic ketoacidosis, or metabolic crisis 3, 5

Hydration Status Assessment

Determine the degree of dehydration to guide rehydration strategy:

• Mild dehydration (3-5% deficit): Slightly dry mucous membranes, increased thirst, normal mental status 1, 4
• Moderate dehydration (6-9% deficit): Sunken eyes, decreased skin turgor, reduced urine output, tenting of skin when pinched 1, 4
• Severe dehydration (≥10% deficit): Severe lethargy, prolonged skin tenting, cool extremities, minimal urine output, signs of shock 1, 4

Rehydration Strategy Based on Severity

For Mild to Moderate Dehydration (No Red Flags Present)

Initiate oral rehydration therapy with small, frequent volumes of ORS (5 mL) every 1-2 minutes using a spoon or syringe, gradually increasing as tolerated. 1, 6, 4

• Administer 50 mL/kg of ORS over 2-4 hours for mild dehydration 1, 6
• Administer 100 mL/kg of ORS over 2-4 hours for moderate dehydration 1, 6
• Replace each vomiting episode with an additional 2 mL/kg of ORS 4, 6
• Never allow the child to drink large volumes at once – this worsens vomiting; controlled small-volume administration is critical 4, 6
• Over 90% of children with vomiting can be successfully rehydrated orally using this approach 4, 2, 6

For Severe Dehydration or Shock

Begin immediate IV rehydration with 20 mL/kg boluses of Ringer's lactate or normal saline until pulse, perfusion, and mental status normalize, then transition to oral therapy. 4, 6

Pharmacologic Management

Antiemetic Therapy

Consider ondansetron (0.2 mg/kg orally or 0.15 mg/kg parenterally, maximum 4 mg) for children with persistent vomiting to improve tolerance of oral rehydration. 2, 3

• Ondansetron should only be used after adequate hydration is being established, not as first-line therapy 2
• It is particularly useful when vomiting impedes oral intake despite small-volume ORS administration 3, 5
• The FDA label indicates safety and effectiveness in pediatric patients 4 years and older 7

Medications to AVOID

Do NOT administer antimotility drugs (loperamide) to children under 18 years with vomiting and diarrhea – they can cause serious complications including ileus and death. 4, 1, 2

• Nonspecific antidiarrheal agents (kaolin-pectin, loperamide) do not reduce fluid losses and have documented serious adverse effects 4
• Antibiotics are generally not indicated unless there is evidence of bacterial infection (high fever, bloody diarrhea, symptoms >5 days) 2

Nutritional Management

Continue age-appropriate diet during or immediately after rehydration – therapeutic starvation is contraindicated. 6, 2

• For a 10-year-old, recommended foods include starches, cereals, yogurt, fruits, and vegetables 4, 2, 6
• Avoid foods high in simple sugars and fats 4, 2
• Do not withhold food during rehydration as this reduces enterocyte renewal and increases intestinal permeability 6

Diagnostic Evaluation

If red flags are present or the cause is not apparent after initial assessment:

• Abdominal X-ray if signs of obstruction are present 5
• Serum electrolytes, blood gases, renal and liver function tests for any child with dehydration or red flag signs 3
• Consider metabolic causes (diabetic ketoacidosis, inborn errors of metabolism) if altered mental status or recurrent episodes 3, 8
• Evaluate for cyclic vomiting syndrome if there is a pattern of recurrent, stereotypical episodes separated by symptom-free intervals 8

Common Pitfalls to Avoid

• Allowing ad libitum drinking from a cup or bottle – this is a frequent mistake that worsens vomiting; always use controlled small-volume administration 4, 6
• Using inappropriate fluids like apple juice, Gatorade, or commercial soft drinks for rehydration 6
• Withholding food during or after rehydration – early refeeding is essential 6, 4
• Diagnosing viral gastroenteritis without considering other causes – this should be a diagnosis of exclusion after ruling out more serious conditions 9

Instructions for Return to Care

Parents should return immediately if:

• Vomiting becomes bilious (green) or bloody 1, 2
• Child becomes increasingly lethargic or difficult to arouse 1, 6
• Urine output decreases significantly 1, 6
• Persistent vomiting despite oral rehydration attempts 2, 6
• Development of abdominal distension or severe tenderness 2