Hospital Management

• Monitor vital signs, cardiac rhythm, urine output, and O₂ saturation closely, and watch for evidence of cranial nerve dysfunction (e.g., ptosis), which may precede difficulty swallowing or respiratory insufficiency.
• Note the level of swelling and the circumference of the affected limb every 15 min until swelling has stabilized.
• Treat shock initially with isotonic saline (20-40 mL/kg IV); if hypotension persists, try 5% albumin (10-20 mL/kg IV) and vasopressors.
• Begin the search for appropriate, specific antivenom early in all cases of known venomous snakebite. In the United States, round-the-clock assistance is available from regional poison control centers.
  1. Any evidence of systemic envenomation (systemic symptoms or signs, laboratory abnormalities) and significant, progressive local findings (e.g., swelling that crosses a joint or involves more than half of the bitten limb) are indications for antivenom administration.
  2. Treating physicians should seek advice from snakebite experts regarding indications for and dosing of antivenom. The duration of antivenom administration depends on the offending snake species, but multiple doses are not effective in reversing bite responses that have already been established (e.g., renal failure, established paralysis, necrosis).
  3. Worldwide, antivenom quality varies; rates of anaphylactoid reaction can exceed 50%, prompting some authorities to recommend pretreatment with IV antihistamines (diphenhydramine, 1 mg/kg to a maximum of 100 mg; and cimetidine, 5-10 mg/kg to a maximum of 300 mg) or even a prophylactic SC or IM dose of epinephrine (0.01 mg/kg, up to 0.3 mg). CroFab, an antivenom used in the United States against North American pit viper species, poses a low risk of allergy elicitation.
  4. A trial of acetylcholinesterase inhibitors should be undertaken for pts with objective evidence of neurologic dysfunction because this treatment may cause neurologic improvement in pts bitten by snakes with postsynaptic neurotoxins.
• Elevate the bitten extremity above heart level once antivenom administration has been initiated.
• Update tetanus immunization.
• Observe pts for muscle-compartment syndrome.
• Observe pts with signs of envenomation in the hospital for at least 24 h. Pts with “dry” bites should be watched for at least 8 h because symptoms are commonly delayed.