Background and Rationale Inhospital cardiac arrest still constitutes an important clinical problem with survival to discharge ranging within 0-42% (most common range = 15-20%) (1). Survival after witnessed, pulseless ventricular fibrillation/tachycardia (VF/VT) that is responsive to one or two direct current countershock(s) may exceed 30%. However, survival after inhospital asystole, pulseless electrical activity, or refractory VF/VT (defined as not responsive to two countershocks) may be substantially lower (i.e., 5-10%) (2). As in nonsurvivors, both endogenous vasopressin and adrenocorticotrophin are reduced compared to survivors (3,4), the investigators hypothesize that the addition of exogenous vasopressin during cardiopulmonary resuscitation (CPR) (5) and of steroids during and after CPR may increase the rates of return of spontaneous circulation (ROSC) and improve post-arrest survival. This hypothesis is supported by the single-center results of NCT 00411879. Thus, the investigators intend to either refute or provide definitive evidence supporting this hypothesis (and its generalizability) by conducting the present multicenter, randomized, controlled clinical trial of inhospital cardiac arrest.