Snake Toxicity

Excerpt

Venomous snakes inflict considerable morbidity and mortality worldwide, although specific data on the total number of venomous snakebites globally are lacking. In the United States, approximately 7,000 to 8,000 venomous snakebites occur each year, with about 5 to 10 deaths reported per year, although there is no mandated reporting for snakebites, so these data are likely incomplete. Notably, bees are responsible for significantly more deaths than snakes in the United States.

Patients with venomous snakebites present with signs and symptoms that can include superficial puncture wounds, localized pain and swelling, nausea, vomiting, muscle cramping, dizziness, numbness, tingling around the mouth, dyspnea, life-threatening coagulopathy, and shock. Pre-hospital treatments, including the application of ice, alcohol consumption, and wound incisions and oral suction of venom, are not recommended. Evidence supports initial conservative management, such as immobilization. In North America, the use of lymphatic constriction bands is not advised as these are reserved for venoms with significant neurotoxic effects only. Otherwise calming the patient and encouraging oral fluid intake prior to rapid evacuation to an emergency center where definitive care can be rendered. Initial assessment of the patient with a snakebite should include laboratory studies to evaluate for hematologic, neurologic, renal, and cardiovascular derangements. Antivenom is the definitive treatment, although the specific type of antivenom depends on the snake species. The previously used horse-serum derived full immunoglobulin antivenom has now largely been replaced by sheep-derived Fab antivenom (FabAV or Fab) and a recently safer horse-derived F(ab)2.