(219) Chilled to the Bone: A Case of Refractory VF Arrest Managed With VA ECMO

Introduction: We present a case of out of hospital cardiac arrest with hypothermia and refractory ventricular fibrillation (VF) managed by extracorporeal membrane oxygenation (ECMO) and good neurologic outcome.

Description: A 45-year-old male was found down outdoors in winter. Cardiopulmonary resuscitation (CPR) was initiated in the field with a rhythm of VF and return of spontaneous circulation (ROSC). A pulse was again lost en route with a rhythm of VF. He was visibly without traumatic injury; core temperature was found to be 72.9 F. Internal and external rewarming measures were initiated. With automatic chest compressor in place, defibrillation, judicious potassium repletion, and multiple anti-arrhythmic therapies were delivered without resolution of VF. Bifemoral veno-arterial (VA) ECMO was initiated with controlled rewarming. Core temperature improved to 79F, and the patient began to move spontaneously and purposefully. He was sedated; CT scan was without major injury. After continued rewarming, additional potassium repletion, and defibrillation, normal sinus rhythm (NSR) was restored. Subsequently, significant desaturation was noted with right radial PaO2 of 33mmHg. Bedside echocardiogram revealed significant improvement in cardiac function and left internal jugular vein return cannula was placed with a presumed diagnosis of differential hypoxia (North/South Syndrome). With placement of additional internal jugular return cannula oxygen saturation improved significantly. He was weaned from ECMO support and decannulated 48 hours later and discharged home after 19 days neurologically intact.

Discussion: With corroborating reports, we later established approximately 109 minutes between initial arrest and ECMO initiation with approximately 4 hours to sustained restoration of NSR. The degree of protective hypothermia and controlled rewarming utilizing ECMO with multiple well-coordinated medical services likely contributed to his favorable outcome. The neuroprotective effects of unintentional hypothermia have been well documented as has ECMO as a therapy in refractory hypothermia. The prolonged time of refractory hypothermia and ventricular fibrillation reminds us of the importance of establishing normothermia before prognostication in out of hospital cardiac arrest.