A review of 95 pit viper envenomations in Northcentral Florida (2018-2020)

The medical records of 95 pit viper envenomations in client-owned dogs presented to an academic emergency hospital in the Southeastern United States during the period spanning 2018 and 2020 were retrospectively examined. This study's primary objectives were to record the clinical abnormalities and treatment responses associated with envenomation and their relation to outcome. Approximately 80% of the bites involved the head region associated with varying degrees of hemorrhagic lymphedema. Some of the most common additional symptoms observed were; hypotension (10%), cardiac dysrhythmias (17%), and coagulopathy (21%). Treatment in most cases consisted of intravenous fluids, antivenom, and analgesic drugs. Blood products were used as indicated for anemia and persistent bleeding. The average dose of the F('ab')₂ was 1-2 vials. Additional vials (3-22) were administered as needed to counteract persistent or recurrent coagulopathy and hemolysis. Only 3% of the dogs had mild clinical signs of Type 1 hypersensitivity during their treatment period. Antihistamine use at the tertiary hospital was restricted to the three dogs showing signs of a suspected allergic reaction in response to antivenom administration; these patients received diphenhydramine intramuscularly. A glucocorticoid drug was used in only one dog prior to referral but not subsequently. Ninety dogs had a good outcome, while five died. Historically, pit viper envenomation in dogs in the southeastern United States has been a potentially life-threatening problem. Most dogs will survive if treated promptly and appropriately with adequate amounts of intravenous fluids, and antivenom titrated on severity of clinical presentation.