The use of amiodarone for in-hospital cardiac arrest at two tertiary care centres

BACKGROUND: Although amiodarone significantly increases survival to hospital admission when used in resuscitation of out-of-hospital pulseless ventricular tachycardia and fibrillation, there are limited data on its utility for in-hospital arrests. OBJECTIVES: To determine whether the use of amiodarone, as recommended by the year 2000 American Heart Association Advanced Cardiac Life Support guidelines, improved survival following its introduction to the resuscitation algorithm at two tertiary care institutions. METHODS: Charts of 374 cardiac resuscitations were retrospectively studied at the two institutions. Basic survival outcomes and demographic data were recorded for cardiac arrests with ventricular tachyarrhythmias qualifying for administration of antiarrhythmic agents. RESULTS: Qualifying rhythms were present in 95 patients. Clinical uptake of amiodarone was limited. In the 36 patients who received amiodarone, survival of resuscitation was 67% versus 83% (P=0.07) in the 59 patients receiving only other antiarrhythmic agents (chiefly lidocaine [94%]), while survival to discharge was 36.1% and 55.9% (P=0.06) in these two groups, respectively. CONCLUSIONS: Following two years' experience with the introduction of intravenous amiodarone for resuscitation in the institutions, use was less than 50% and no clinically observable survival benefit could be documented. Possible explanations for the difference between this experience and that found in out-of-hospital resuscitation trials include differing patient populations and operator bias during resuscitation. These results should provoke other institutions to question whether amiodarone has improved survival of cardiac arrest under the conditions prevailing in their hospitals. A patient registry or prospective, randomized trial will be required to assess what parameters affect the success of intravenous amiodarone for resuscitation in-hospital.