Induction of Mild Hypothermia Following Out-of-hospital Cardiac Arrest

In this study we will randomize 1,200 cardiac arrest patients who have return of spontaneous circulation (ROSC) to hypothermia with rapid infusion of 2 liters of 4oC Normal Saline IV solution over 20 to 30 minutes, IV sedation and muscle paralysis or to standard of care following ROSC. The primary objective of this study will be to determine whether induction of mild hypothermia using an infusion of cold normal saline will improve the proportion of patients who survive and are discharged awake from the hospital. Hypothesis: In cardiac arrest patients who achieve ROSC in the field, initiation of hypothermia by infusion of cold normal saline will result in a greater proportion of cardiac arrest patients discharged awake from the hospital compared to standard care.