What is the standard drug protocol for a snake bite?

Standard Drug Protocol for Snake Bites

The standard drug protocol for snake bites centers on prompt administration of antivenom, with an initial dose of 4-6 vials of CroFab administered as soon as possible after envenomation, followed by additional doses until initial control is achieved. 1

Initial Assessment and First Aid

• DO:

  • Call emergency services immediately
  • Rest and immobilize the bitten extremity
  • Remove constricting jewelry

• DO NOT:

  • Apply ice (can cause tissue ischemia)
  • Use suction devices (ineffective except possibly within first 5 minutes)
  • Apply electric shock (harmful)
  • Apply tourniquets (harmful)
  • Use pressure immobilization bandaging for North American pit vipers 2, 1

Antivenom Administration Protocol

Indications for Antivenom

• All moderate to severe envenomations
• Selected mild cases with progressive symptoms
• Grading system (I-IV) should guide administration decisions 3

Dosing Guidelines

• Initial dose: 4-6 vials IV (may range from 4-12 vials based on severity)
• Administration: Reconstitute and dilute according to manufacturer's instructions
• Setting: Must be administered in a hospital setting with monitoring for adverse reactions
• Timing: Most effective when given within four hours of the bite 1, 4

Antivenom Types

• CroFab (sheep-derived antigen binding fragment ovine): Less allergenic, preferred option
• Equine-derived antivenin: Traditional standard of care 1, 3

Pre-Administration Requirements

• Mandatory skin testing before administration to predict anaphylactic reactions
• Have diphenhydramine and epinephrine readily available for potential anaphylaxis 5

Monitoring and Follow-up

• Monitor for up to 1 hour after initial dose

• Initial control is achieved when:

  • Local injury progression stops
  • Systemic symptoms resolve
  • Coagulation parameters normalize or trend toward normal

• Required laboratory tests:

  • Complete blood count
  • Coagulation studies
  • Renal function tests
  • Electrolytes 1

• Monitor for recurrent coagulopathy for at least one week following treatment

• Long-term follow-up is essential as persistent renal involvement may occur in up to 41% of patients 1

Supportive Care

• Respiratory support: Early intubation and mechanical ventilation at first sign of respiratory compromise
• Fluid management: Aggressive fluid resuscitation with normal saline (initial rate 1000 ml/h, then tapered by at least 50% after 2 hours)
• Avoid potassium-containing balanced salt fluids due to risk of hyperkalemia
• Pain control: Administer appropriate analgesics
• Infection prevention: Clean wound and administer broad-spectrum antibiotics
• Tetanus prophylaxis: Determine tetanus status and administer tetanus toxoid if necessary 1, 5

Special Considerations

• Pregnant patients: Should receive the same treatment as non-pregnant individuals, including antivenom when indicated
• Sickle cell disease patients: Require close monitoring for vaso-occlusive crisis triggered by envenomation
• Surgical intervention: Fasciotomy is now reserved for rare cases with elevated intracompartment pressures 1, 5

Common Pitfalls to Avoid

1. Delayed antivenom administration: Early administration is critical for preventing irreversible venom-mediated effects 4
2. Inappropriate first aid: Outdated techniques like arterial tourniquets, ice application, and wound incisions are harmful
3. Inadequate monitoring: Failure to monitor for complications like coagulopathy, renal failure, and allergic reactions
4. Insufficient antivenom dosing: Underdosing can lead to treatment failure and progression of envenomation
5. Failure to recognize systemic symptoms: Early signs like nausea, vomiting, headache, and abdominal pain should prompt immediate antivenom administration 1, 4