On Call: Nausea & Vomiting
Basics
Common Causes of Nausea
- Medications – Especially Opioids & Anesthesia Postoperatively
- Gastrointestinal Pathology:
- Small Bowel Obstruction
- Ileus
- Gastroparesis
- Symptomatic Cholelithiasis/Cholecystitis
- Gastroenteritis
- Pancreatitis
- Appendicitis
- Mesenteric Ischemia
- Gastroesophageal Reflux Disease (GERD)
- GI Bleed
- Liver Failure
- Neurologic Pathology:
- Vertigo
- Migraine
- Migraine
- Intracranial Hemorrhage
- Pregnancy
- Bulimia
- Cyclic Vomiting Syndrome
Principal Neurotransmitter Mediators
- Muscarinic (M1)
- Dopamine (D2)
- Histamine (H1)
- Serotonin (5-HT-3)
- Neurokinin-1 (NK-1)
Effects of Vomiting
- Risk for Aspiration
- Dehydration
- Metabolic Derangements – Hypokalemic Hypochloremic Metabolic Alkalosis
Evaluation
Subjective
- Abdominal Pain
- Associated Factors
- Last Bowel Movement & Passage of Flatus
- Frequency of Vomiting
- Hematemesis
- Heartburn
History
- Recent Medication Taken
- History of Bowel Obstruction
- Surgical History
Physical Exam
- Vital Signs
- Abdominal Tenderness
- Abdominal Distention
Further Work Up to Consider Depending on Findings
- Labs (CBC, CMP, etc.)
- Abdominal X-Ray (AXR)
- Abdominal CT
- Upper Endoscopy
Treatment
General Treatment Approach
- First Determine the Cause
- Avoid Any Causative Agents – Opioids, etc.
- Antiemetic Medication
- If One Fails, Try Another Medication from Another Class
- *See Pharmacology & Anesthesia: Antiemetics
- Consider Nasogastric Tube Placement for Ileus or Obstruction
Antiemetic Pharmacology
- Classes:
- Serotonin (5-HT3) Antagonists – Ondansetron (Zofran)
- Dopamine Antagonists
- Phenothiazines: Prochlorperazine (Compazine) or Promethazine (Phenergan)
- Butyrophenones: Haloperidol (Haldol) or Droperidol (Inapsine)
- Metoclopramide (Reglan)
- Anticholinergic Agents – Scopolamine Patch
- Antihistamines – Diphenhydramine (Benadryl) or Dimenhydrinate (Dramamine)
- Other Agents:
- NK-1 Receptor Antagonist – Aprepitant
- Cannabinoids
- Glucocorticoids – Dexamethasone or Methylprednisolone
- *See Pharmacology & Anesthesia: Antiemetics
Small Bowel Obstruction & Ileus Management