What is the initial workup and management for a snake bite in the emergency department (ED)?

Initial Workup and Management for Snake Bites in the Emergency Department

The definitive treatment for snakebites is antivenom, which should be administered in a medical facility after immediate activation of emergency services for any person bitten by a venomous or possibly venomous snake. 1, 2

Initial Assessment and Stabilization

• Activate emergency services immediately for any person bitten by a venomous or possibly venomous snake 1, 2
• Perform rapid assessment of airway, breathing, and circulation (ABC) 3
• Remove rings and other constricting objects from the bitten extremity to prevent damage from swelling 1, 2
• Rest and immobilize the bitten extremity to minimize venom absorption 1, 2
• Document the time of the bite and, if possible, identify the snake species (without endangering anyone) 3

Clinical Evaluation

• Assess for local signs of envenomation: fang marks, pain, swelling, ecchymosis, and tissue necrosis 4, 3
• Monitor for systemic manifestations:
  • Hemotoxic effects: coagulopathy, bleeding, hypotension 4, 5
  • Neurotoxic effects (especially with coral snake bites): paralysis, respiratory distress 1, 2
  • Cardiovascular effects: hypotension, shock 3, 5
  • Renal effects: hematuria, renal failure 4, 5

Laboratory and Diagnostic Workup

• Complete blood count (CBC) 3, 5
• Coagulation studies (PT, PTT, INR, fibrinogen, D-dimer) 3, 5
• Comprehensive metabolic panel including renal function 4, 3
• Urinalysis to assess for hematuria or myoglobinuria 3, 5
• Type and cross-match for potential blood product administration 3
• ECG for patients with systemic symptoms or comorbidities 3

Treatment Protocol

• Grade the severity of envenomation to guide antivenom administration:

  • Grade I: Local swelling and pain only
  • Grade II: Progression beyond the bite site but not involving the entire extremity
  • Grade III: Severe swelling involving the entire extremity with systemic signs
  • Grade IV: Severe envenomation with immediate life-threatening manifestations 4

• Administer antivenom as the cornerstone of treatment for venomous snakebites 2, 4, 3

  • CroFab (Crotalidae Polyvalent Immune Fab) is the preferred antivenom for pit viper bites in the US due to lower allergenic potential 4, 3
  • Coral snake antivenom for Elapidae envenomations 1, 2

• Provide supportive care:

  • Intravenous fluids for hypotension 3, 5
  • Pain management with appropriate analgesics 3, 5
  • Tetanus prophylaxis as indicated 5
  • Consider antibiotics only if signs of infection develop (not routinely recommended) 5

Harmful Practices to Avoid

• Do NOT apply ice to a snakebite wound as it may cause tissue injury 1, 2
• Do NOT use suction devices as they are ineffective for venom removal 1, 2, 4
• Do NOT apply electric shock as it is ineffective and potentially harmful 1, 2
• Do NOT apply tourniquets as they can worsen local tissue injury 1, 2, 4
• Do NOT use pressure immobilization bandaging for North American pit viper bites (may be appropriate for coral snake bites) 1, 2, 6
• Do NOT make incisions at the bite site 4, 5

Monitoring and Disposition

• Continuous monitoring of vital signs, affected limb circumference, and laboratory parameters 3
• Serial neurological examinations for patients with suspected neurotoxic envenomation 1, 3
• Admission criteria:
  • All patients with moderate to severe envenomation 3
  • Patients requiring antivenom administration 3, 5
  • Patients with comorbidities or at extremes of age 3

Special Considerations

• Coral snake bites (Elapidae) produce primarily neurotoxic effects rather than tissue injury and require specific management 1, 2
• Pregnant patients, children, and elderly patients may require more aggressive treatment 3
• Surgical intervention with fasciotomy is now reserved for rare cases with confirmed compartment syndrome, not based solely on clinical appearance 4