Abstract 1767: The Effect of Vasopressin for Patients with Prolonged Cardiopulmonary Resuscitation (CPR) with Non-Shockable Rhythm
Background: The AHA guidelines 2005 for CPR recommended that vasopressin may replace either the first or second epinephrine dose in the treatment of cardiac arrest (class Indeterminate), because a multicenter trial of vasopressin showed that patients with asystole had significant improvement in the rate of survival to discharge, but not neurologically intact survival when vasopressin was used as the initial vasopressor compared with epinephrine. However, few clinical studies of vasopressin are available for patients with prolonged CPR with non-shockable rhythm.
Methods: We conducted a prospective randomized controlled study of vasopressin. Patients were enrolled if they had out-of-hospital asystole or pulseless electrical activity as an of initial cardiac rhythm, and if they were transported under CPR without administration of any vasopressors. They were randomly assigned to receive 4 injections of either 40 IU of vasopressin or 1mg of epinephrine. The study end points were return of spontaneous circulation (ROSC), 24-hour survival, and survival to hospital discharge.
Results: A total of 330 patients were enrolled. The two treatment groups had similar clinical profiles and call-to-drug-administration interval (median; 34minutes with vasopressin group vs 36minutes with epinephrine group). There were no significant differences between the vasopressin group (n = 166) and the epinephrine group (n = 164) in the ROSC (22.9% vs 21.3%), the 24-hour survival (15.1% vs 15.2%), and the survival to hospital discharge (4.8% vs 3.0%), a favorable neurological outcome at the time of hospital discharge (3.0% vs 1.2%). The circulation level of vasopressin ranged from 1.6 to 496.0pg/ml, with a median of 80pg/ml. No significant differences were observed in circulating vasopressin level on arrival at the emergency room between the patients with ROSC and those with Non-ROSC (72.2 vs 81.8pg/ml), and between the patients with survival to hospital discharge and those with death in hospital (89.9 vs 79.5pg/ml).
Conclusions: Although vasopressin can be use as an alterative to epinephrine in patients with asystole or pulseless electrical activity for prolonged CPR, vasopressin has not excellent supporting evidence as compared with epinephrine.