2P and 5D in Snake Bite Management
Understanding the Terminology
The terms "2P" and "5D" do not represent standard, evidence-based protocols in snakebite management and should not guide clinical decision-making. These mnemonics are not referenced in current American Heart Association guidelines, American College of Medical Toxicology recommendations, or systematic reviews of snakebite management 1, 2, 3, 4.
Evidence-Based First Aid: What Actually Works
Pressure and Immobilization (The Real "P")
Apply pressure immobilization bandaging at 40-70 mm Hg for upper extremities and 55-70 mm Hg for lower extremities around the entire bitten limb, combined with splinting. 1, 2, 3
- This technique is particularly critical for neurotoxic envenomations (kraits, cobras, sea snakes) where it significantly reduces lymphatic venom absorption 2, 3, 5
- A practical field estimation: apply a bandage tight enough to allow insertion of one finger underneath 1
- Important caveat: For cytotoxic/hemotoxic venoms (vipers), pressure immobilization may concentrate venom locally and potentially worsen tissue damage 2, 3
What to Avoid (The Real "Don'ts")
Do NOT apply suction—it removes only 0.04% of venom and may accelerate venom invasion. 1, 2, 3
- Do NOT apply ice (causes additional tissue injury) 2, 3, 5
- Do NOT use electric shock (ineffective and harmful) 2, 3, 5
- Do NOT apply tourniquets (worsens local tissue injury) 2, 3, 5
- Do NOT delay transport to attempt ineffective first aid 2, 3, 5
Definitive Treatment: Antivenom Dosing
For common krait bites, administer 10 vials of antivenom as the initial dose. 2, 3
- Antivenom is the cornerstone of treatment and should be administered as soon as possible 2, 6, 7
- Establish intravenous access before antivenom administration 3
- Ensure airway management and ventilatory support, particularly for neurotoxic envenomations that can cause respiratory paralysis 2, 3
Critical Clinical Pitfalls
- Remove all rings, watches, and constricting items immediately before swelling develops to prevent ischemic injury 2, 3, 5
- Activate emergency medical services immediately—definitive treatment requires hospital-based antivenom 2, 3, 5
- Minimize patient movement during transport—physical activity increases systemic venom absorption through lymphatic flow 2, 5
- Do not assume no envenomation based on lack of local symptoms—some venoms (particularly neurotoxic ones) cause minimal local findings despite life-threatening systemic toxicity 5