 The addition of an Extracorporeal-Cardiopulmonary Resuscitation ECPR service to a region may improve the survival of young patients with sudden unexpected cardiac arrest.The primary aim of this study is to determine the benefit of the systematic integration of ECPR services into the out-of-hospital cardiac arrest management algorithm. This study is a controlled parallel group design with group allocation based on region of treatment. The investigators will compare the outcomes of ECPR-eligible patients in the intervention region, in comparison to patients meeting the same criteria in a comparable setting. 