What is the workup for intermittent vomiting?

From the Guidelines

The workup of intermittent vomiting should begin with a thorough history and physical examination to identify potential causes, followed by initial diagnostic tests including complete blood count, comprehensive metabolic panel, amylase/lipase, and urinalysis, as well as empiric treatment with antiemetics such as ondansetron 4-8mg every 8 hours as needed 1. The key elements to consider in the history and physical examination include timing of symptoms, associated symptoms like abdominal pain or diarrhea, and potential triggers such as medications, foods, or stress.

• Initial diagnostic tests should assess for infection, electrolyte abnormalities, and organ dysfunction.
• If symptoms persist, an upper endoscopy may be warranted to evaluate for structural abnormalities, gastritis, or ulcers.
• Additional testing might include abdominal ultrasound or CT scan to assess for gallbladder disease, pancreatitis, or obstruction.
• For patients with neurological symptoms, brain imaging should be considered.
• Empiric treatment while awaiting diagnosis may also include proton pump inhibitors like omeprazole 20-40mg daily if gastritis is suspected, and patients should maintain hydration and follow a bland diet during episodes.
• The use of antiemetics such as 5-Hydroxytryptamine3 (5-HT3) receptor antagonists (eg, ondansetron, granisetron) or Neurokinin (NK-1) receptor antagonists (eg, aprepitant, tradipitant, casopitant, rolapitant) may be beneficial in improving nausea and vomiting, as shown in recent studies 1.
• The choice of antiemetic should be based on the patient's specific needs and the potential side effects of the medication, with consideration of the most recent and highest quality evidence available 1.

From the Research

Initial Evaluation

• The initial evaluation of a patient with intermittent vomiting involves assessing airway, breathing, and circulation, as well as hydration status and red flag signs 2
• Red flag signs include bilious or bloody vomiting, altered sensorium, toxic/septic/apprehensive look, inconsolable cry or excessive irritability, severe dehydration, concern for symptomatic hypoglycemia, severe wasting, and Bent-over posture 2
• A careful history of related factors is essential to guide the initial evaluation and narrow the differential diagnosis, including associated symptoms, timing of onset and duration of symptoms, exacerbating or relieving factors, alarm symptoms, medication and substance use, relationship with recent food ingestion, and comorbidities 3, 4

Differential Diagnosis

• The differential diagnosis for intermittent vomiting is broad and includes gastrointestinal, infectious, metabolic, neurologic, psychiatric, and medication-related causes 3, 4
• Important life-threatening causes in infancy include congenital intestinal obstruction, atresia, malrotation with volvulus, necrotizing enterocolitis, pyloric stenosis, intussusception, shaken baby syndrome, hydrocephalus, inborn errors of metabolism, congenital adrenal hypoplasia, obstructive uropathy, sepsis, meningitis, and encephalitis 2
• In older children and adults, causes such as appendicitis, intracranial mass lesion, diabetic ketoacidosis, Reye's syndrome, toxic ingestions, uremia, and meningitis should be considered 3, 2, 5

Management

• Management priorities include treatment of dehydration, stoppage of oral fluids/feeds, and decompression of the stomach with nasogastric tube in patients with bilious vomiting 2
• Antiemetic medications such as ondansetron can be effective in reducing symptoms of acute nausea and vomiting 6, 2
• Nonpharmacologic management options include fluid and electrolyte replacement, small, frequent meals, and avoidance of trigger foods 3, 4
• Pharmacologic therapy should be used for the shortest time necessary to control symptoms, and treatment should be directed at the underlying cause of symptoms and the neurotransmitters involved in central and peripheral pathways of nausea and vomiting 3, 4