C52-10 Accidental Severe Hypothermic Cardiac Arrest With Full Neurologic Recovery Without ECMO: Considerations for Extracorporeal Support and Prognostication

Abstract Introduction Accidental hypothermia, defined as core temperature below 95 degrees Fahrenheit (F), can precipitate cardiac arrest and requires rapid, coordinated resuscitation. While profound hypothermia increases susceptibility to dysrhythmias and circulatory collapse, it also confers neuroprotection through reduced cerebral metabolic demand. Standard management includes high-quality cardiopulmonary resuscitation (CPR), active rewarming, airway protection, and hemodynamic support. Extracorporeal membrane oxygenation (ECMO) is increasingly used for rewarming and circulatory support in severe hypothermic cardiac arrest, though candidacy criteria vary by institution. The Hypothermia Outcome Prediction after Extracorporeal Life Support (HOPE) score, a validated tool that incorporates age, sex, core temperature, serum potassium, mechanism of hypothermia (asphyxial vs non-asphyxial), and duration of CPR, estimates survival and guides ECMO decisions. Epidemiologic data emphasize salvageability: in the International Hypothermia Registry (2010-2020), hypothermic cardiac arrest occurred in ∼36% of 201 patients, with approximately 36% survival. We present a case of unwitnessed hypothermic cardiac arrest in a patient deemed ineligible for ECMO due to age who achieved full neurologic recovery with conventional management. Description of Case A 66-year-old man with chronic obstructive pulmonary disease, schizophrenia, and cocaine use disorder was found outdoors on a 41F day in unwitnessed cardiac arrest. On arrival, he was pulseless with a core temperature of 82F and a Glasgow Coma Scale of 3. After 30 minutes of CPR for pulseless electrical activity, return of spontaneous circulation was achieved. The ECMO team declined cannulation due to an institutional exclusion criterion of age greater than 65 years. He was intubated, treated with vasopressors, and actively rewarmed to 98.6F (37 degrees Celsius) over approximately 3.5 hours. Urine was cocaine positive. Vasopressor support was discontinued within 28 hours, and neurologic recovery was evident by 48 hours. He was discharged on hospital day 14 without neurologic deficits. Discussion Despite an unwitnessed arrest, non-shockable rhythm, and a calculated HOPE score of -1.34 corresponding to an estimated survival probability of approximately 21%, this patient achieved full neurologic recovery without ECMO. This case reinforces that early high-quality CPR and controlled rewarming can yield favorable outcomes in severe accidental hypothermia. While ECMO has transformed management in many centers, strict age-based exclusion criteria may overlook physiologic potential and may deny potentially beneficial therapy. Prognostication should integrate structured tools such as the HOPE score with clinical context, institutional resources, and patient-specific factors rather than age alone. This case supports individualized evaluation of ECMO candidacy and highlights that meaningful recovery remains possible with conventional management. This abstract is funded by: None