ECMO as salvage therapy for severe ARDS complicating Crotalus atrox envenomation

BackgroundSnakebite envenomation is a global health problem, though rarely encountered in Europe outside captive settings. The Western diamondback rattlesnake (Crotalus atrox) is one of the most medically important North American pit vipers, with venom capable of provoking profound coagulation disorders and systemic toxicity. Respiratory complications are exceedingly rare, and the role of extracorporeal membrane oxygenation (ECMO) in this context has not been previously described.Case presentationWe report the case of a 36-year-old man who sustained a facial bite from a captive Crotalus atrox. On arrival, he presented with rapidly progressive facial and pharyngeal edema requiring emergent intubation. Laboratory investigations revealed disseminated intravascular coagulation (DIC), characterized by thrombocytopenia, hypofibrinogenemia, prolonged INR and aPTT, markedly elevated D-dimers, and ROTEM evidence of impaired clot formation. High-dose antivenom and targeted factor replacement were administered. Within hours, the patient developed pulmonary hemorrhage and acute respiratory distress syndrome (ARDS), unresponsive to maximal conventional therapy. Veno-venous extracorporeal membrane oxygenation (V-V ECMO) was initiated as rescue support, resulting in rapid stabilization of gas exchange. The subsequent ICU course was complicated by acute kidney injury and seizures during sedation tapering, all managed successfully. ECMO was explanted on the 4th postcannulation day, tracheostomy was performed on the 6th postcannulation day, and the patient was decannulated on the 16th postcannulation day. He was discharged home on the 22nd postcannulation day in good general condition, without residual organ dysfunction.ConclusionThis case highlights the potential for Crotalus atrox envenomation to cause fulminant systemic complications including DIC and ARDS. It also demonstrates that V-V ECMO can be safely and effectively applied as salvage therapy in venom-induced ARDS, provided it is initiated promptly within specialized centers.