From the Guidelines
The workup for vomiting in infants should begin with a thorough clinical evaluation, including history and physical examination, to identify potential causes and differentiate between nonbilious and bilious vomiting. According to the American College of Radiology 1, a diagnostic workup should start with a thorough clinical evaluation, as most cases of vomiting in infants are benign and can be diagnosed based on history and physical examination. Initial evaluation should include assessment of hydration status, vital signs, and abdominal examination.
Key considerations in the workup include:
- Differentiation between nonbilious and bilious vomiting, as bilious vomiting suggests a more distal obstruction and requires prompt evaluation for underlying pathology
- Assessment for signs of dehydration, such as decreased urine output, dry mouth, and sunken eyes
- Laboratory tests, such as complete blood count, comprehensive metabolic panel, and urinalysis, to rule out underlying infections or metabolic disorders
- Imaging studies, such as abdominal X-rays or ultrasound, if obstruction or other intra-abdominal pathology is suspected
It is essential to tailor the workup to the patient's presentation, as vomiting can result from numerous conditions, including gastroenteritis, metabolic disorders, central nervous system disorders, or gastrointestinal obstruction 1. In cases of severe or persistent vomiting, consideration of intravenous fluids and antiemetics, such as ondansetron or metoclopramide, may be necessary to manage symptoms and prevent complications.
From the Research
Vomiting Workup
- The clinical approach to nausea and vomiting can be challenging due to the numerous possible underlying causes and diagnostic and therapeutic options 2
- A practical 5-step approach to the clinical evaluation and treatment of nausea and vomiting includes:
- Defining what the patient means by nausea and vomiting
- Determining whether symptoms are acute or chronic
- Considering medication or toxin adverse effects
- Using the patient's presentation, severity of symptoms, and physical examination findings to formulate a differential diagnosis and guide evaluation
- Directing treatment based on knowledge of neurotransmitters and receptors involved in the emetic pathways 2
- The likely cause of acute nausea and vomiting can usually be determined by history and physical examination, while chronic nausea and vomiting may require further evaluation, including laboratory testing and imaging studies 3
Diagnostic Considerations
- Alarm signs such as dehydration, acidosis, or an acute abdomen warrant additional evaluation 3
- Laboratory testing may include urinalysis, urine pregnancy testing, complete blood count, comprehensive metabolic panel, amylase and lipase levels, thyroid-stimulating hormone level, and stool studies with cultures 3
- Imaging studies may include abdominal radiography, ultrasonography, and computed tomography, while computed tomography of the head should be performed if an acute intracranial process is suspected 3
Treatment Options
- Management of symptoms that are acute in onset or mild in severity may involve an empirical trial of antiemetics without extensive testing 2
- Ondansetron and metoclopramide are commonly used antiemetics, but their efficacy and safety profiles may vary depending on the patient population and clinical context 4, 5, 6
- A randomized controlled trial comparing ondansetron, metoclopramide, and placebo for adults with undifferentiated emergency department nausea and vomiting found similar reductions in nausea severity for all three groups 6