Recombinant Factor VIIa for Treatment of Gastrointestinal Hemorrhage Following Rattlesnake Envenomation

Abstract

North American rattlesnakes possess venom with primarily cytotoxic and hemotoxic properties. When persons are envenomated by these snakes, thrombocytopenia and coagulopathy commonly occur, yet patients rarely develop severe bleeding. This report describes a 44-year-old Native American man bitten on the index finger by an unknown species of rattlesnake. The man developed massive gastrointestinal hemorrhage that was ultimately treated with recombinant factor VIIa. He presented to an emergency department with a depressed level of consciousness, a blood pressure of 60/20 mm Hg, and heart rate of 148 beats per minute. He was diaphoretic and vomiting bright red blood. Initial laboratory results revealed thrombocytopenia and coagulopathy. Despite aggressive fluid resuscitation and administration of blood and antivenom in the emergency department, the patient continued to have profuse upper gastrointestinal bleeding, with hemoglobin as low as 1.8 g/dL. He received fluids, antivenom, and multiple blood products, with cessation of bleeding after administration of recombinant factor VIIa. Esophagogastroduodenoscopy revealed a single Mallory-Weiss tear as the source of hemorrhage. The patient stabilized after 6 hours of aggressive resuscitation but over the next several days developed several complications, including acute renal failure and gram-negative sepsis. The patient died on hospital day 5. In cases of life-threatening hemorrhage after rattlesnake envenomation in which traditional therapy with antivenom and aggressive supportive measures fail, recombinant factor VIIa should be considered as an additional therapeutic option to achieve hemostasis.