Rosen & Barkin's 5-Minute Emergency Medicine Consult (775 page)

DIAGNOSIS

• Symptom duration, frequency, severity:
  
  • Acute, recurrent, chronic, cyclic
    
• Characteristics of vomiting: Timing, description, content of vomitus
  
• Associated symptoms: Pain, fever, diarrhea, neurologic
  
• Past surgical or GI history
  
• Medication and drugs use
  
• Last menstrual period
  
• Complete past medical history
  

• Vital signs:
  
  • Fever: Appendicitis, gastroenteritis, cholecystitis, hepatitis, bowel perforation
    
  • Tachycardia: Dehydration
    
• Head, ears, eyes, nose, throat:
  
  • Abnormal anterior chamber: Glaucoma
    
  • Dry mucous membranes: Dehydration
    
  • Nystagmus: Labyrinthitis, stroke, tumor, intracranial hemorrhage
    
  • Papilledema: Elevated ICP
    
• Abdomen:
  
  • Blood in stool or emesis: Peptic ulcer, Mallory–Weiss tear
    
  • Decreased bowel sounds: Ileus
    
  • Distention, high-pitched bowel sounds, scars or hernias: Intestinal obstruction
    
  • Pain: Appendicitis, cholecystitis, pancreatitis, perforated viscus, ovarian torsion
    
  • Testicular pain: Torsion
    
• Neurologic:
  
  • Abnormal mental status, cerebellar test abnormalities, cranial nerve abnormalities: CNS pathology
    

The workup is aimed at determining the underlying cause of vomiting and excluding dangerous sequelae

• CBC:
  
  • Elevated WBC: Infectious process (e.g., appendicitis, gastroenteritis)
    
  • Elevated hematocrit: Dehydration
    
  • Decreased hematocrit: GI bleed from ulcer
    
• Electrolytes/renal function:
  
  • Prolonged vomiting may cause hypochloremia, hypokalemia.
    
  • BUN/creatinine ratio >20 may indicate dehydration.
    
  • Renal insult may occur from dehydration
    
• Liver/pancreatic function tests:
  
  • Amylase/lipase elevation: Pancreatitis
    
  • AST/ALT elevation: Hepatitis
    
  • Alkaline phosphatase elevation: Cholecystic etiology
    
• Urine analysis:
  
  • WBC, nitrites, leukocyte esterase, bacteria: UTI
    
  • Ketones: Dehydration, DKA
    
  • Pregnancy test in women of childbearing age
    
• Toxicology screen/drug levels:
  
  • For suspected drug toxicity or overdose
    

• Abdominal series (kidney, ureter, bladder/upright):
  
  • Suspected bowel obstruction or perforated viscus
    
• CT abdomen/pelvis:
  
  • Suspected appendicitis, obstruction, nephrolithiasis
    
• CT/MRI head:
  
  • Suspected intracranial etiology
    
• US:
  
  • Suspected biliary disease, gonadal torsion, nephrolithiasis
    

• EKG:
  
  • Suspected MI
    
• Endoscopy:
  
  • Peptic ulcer disease leading to significant GI bleed
    

TREATMENT

• Aimed at stabilizing patient until arrival in the ED, where the workup of underlying cause of vomiting can proceed
  
• Placement of IV, oxygen, cardiac monitor
  
• Begin administration of isotonic fluids in suspected dehydration
  
• Fingerstick glucose in mental status change
  
• Specific protocols may permit antiemetics for motion sickness or other etiologies of vomiting
  

• Address ABCs
  
• Urgent fluid resuscitation if vomiting has led to hypovolemic shock
  
• Urgent antiemetic therapy for patient comfort
  
• Urgent analgesic therapy if indicated
  

• 3 principles of ED treatment:
  
  • Correct fluid, electrolyte, and nutritional deficiencies as a result of vomiting
    
  • Identify and treat underlying cause
    
  • Suppress or eliminate symptoms.
    
• Antibiotics if indicated: UTI, appendicitis, bacterial gastroenteritis
  
• Medications:
  
  • Serotonin antagonists often 1st line treatment:
    
    • Ondansetron, dolasetron, granisetron
      
    • Useful in chemotherapy-induced nausea
      
    • Ondansetron available as an oral dissolving tablet for patients who cannot tolerate pills
      
    • Can cause QT prolongation
      
  • Dopamine D
    ₂
    antagonists also useful in most types of nausea:
    
    • Prochlorperazine, promethazine, metoclopramide, droperidol
      
    • Side effects (e.g., akathisia, dystonia) more common than in serotonin antagonists
      
    • Note black box warnings on use of droperidol (potential QT prolongation and/or torsades de pointes) and promethazine (tissue injury with IV administration)
      
  • Anticholinergic and antihistamine agents useful in labyrinthitis, positional vertigo, and motion sickness:
    
    • Meclizine, diphenhydramine, scopolamine
      
  • Benzodiazepines and glucocorticoids have mild antiemetic properties and can be used as adjuncts
    
• Consultation with other specialties (e.g., surgery, gynecology, gastroenterology) depending on underlying etiology
  

• Diphenhydramine: 25–50 mg IM/IV/PO
  
• Dolasetron: 12.5 mg IV
  
• Droperidol: 0.625–1.25 mg IM/IV
  
• Granisetron: 1 mg IV or 2 mg PO
  
• Hydroxyzine: 25–100 mg IM
  
• Meclizine: 25–50 mg PO
  
• Metoclopramide: 10 mg IM/IV/PO
  
• Ondansetron: 4–8 mg IM/IV/PO
  
• Prochlorperazine: 5–10 mg IM/IV/PO or 25 mg PR
  
• Promethazine: 12.5–25 mg PO/PR/deep IM
  
• Scopalamine: 1.5 mg patch applied behind the ear 4 hr prior to travel
  

• Dopamine-antagonizing antiemetics have potential cardiac side effects:
  
  • The doses of these medications should be reduced in the elderly
    
• Serotonin antagonists are safer in this population:
  
  • Still consider using lower doses and obtaining an EKG to detect QT prolongation prior to administration
    

• Vomiting in children can result from a host of other diagnoses, e.g., structural/anatomical disorders, infections, and metabolic disorders:
  
  • Workup and treatment may therefore be different in children
    

• Vomiting occurs in >25% of pregnancies
  
• Dopamine D
  ₂
  antagonists (e.g., promethazine, chlorpromazine, metoclopramide) or serotonin antagonists (e.g., ondansetron, granisetron) most commonly used
  

• Serotonin antagonists
  
• Dopamine D
  ₂
  antagonists
  

• Anticholinergics
  
• Antihistamines
  
• Benzodiazepines
  
• Glucocorticoids
  

FOLLOW-UP

• Depends on underlying pathology
  
• Significant underlying disease or symptoms necessitating close observation or surgical procedure
  
• Uncontrolled emesis resulting in inability to tolerate food or liquids by mouth
  
• Severe dehydration requiring continued IV fluids
  
• Significant electrolyte disturbances
  
• Unknown etiology of vomiting with inadequate outpatient follow-up
  

• Significant underlying pathology is excluded
  
• Patient is sufficiently hydrated
  
• Emesis is controlled
  
• Close follow-up is arranged (preferably within 24–36 hr)
  

• All patients who are unable to tolerate fluids at home should return to the ED
  
• Patients in whom the etiology of vomiting is unknown or who had electrolyte disturbances should follow-up
  

• Vomiting is a symptom and not a diagnosis:
  
  • It is important to be familiar with the broad differential diagnoses and exclude dangerous etiologies
    
• Many antiemetics have notable side effects, ranging from dystonia to cardiac arrhythmias.
  
  • Know contraindications and treatment of adverse reactions before using these agents
    
• Oral dissolving tablets and suppositories useful to avoid IV and for home care
  

• Longstreth GF. Approach to the adult with nausea and vomiting. Up to Date on-line text.
  www.uptodate.com
  . March 2012.
  
• Malagelada JR, Malagelada C. Nausea and vomiting. In: Feldman M, et al., eds.
  Sleisenger and Fordtran’s Gastrointestinal and Liver Diseases.
  9th ed. Philadelphia, PA: Saunders Elsevier; 2010.
  
• Zun LS, Singh A. Nausea and vomiting. In: Marx JA, et al., eds.
  Rosen’s Emergency Medicine: Concepts and Clinical Practice.
  7th ed. Philadelphia, PA: Mosby Elsevier; 2010.
  

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