Jul 9, 2003

Optimal timing for electrical defibrillation after prolonged untreated ventricular fibrillation

Critical Care Medicine
Julieta D KolarovaRaúl J Gazmuri


It currently is recommended that electrical shocks be delivered immediately on recognition of ventricular fibrillation. However, decreased effectiveness of this approach has been reported after prolonged intervals of untreated ventricular fibrillation. We investigated the optimal strategy for successful defibrillation after prolonged untreated ventricular fibrillation by using a rat model of ventricular fibrillation and closed-chest resuscitation. Controlled, randomized, laboratory study. Research laboratory at a VA hospital. Seventy pentobarbital anesthetized Sprague-Dawley rats. After 10 mins of untreated ventricular fibrillation, four groups of rats were randomized to receive electrical shocks (which we designated as "experimental shocks") immediately before or at 2, 4, or 6 mins of chest compression. Unsuccessfully defibrillated rats received additional shocks (which we designated as "rescue shocks") after 8 mins of chest compression. The number of rats that restored spontaneous circulation after the experimental shocks increased with increasing duration of the predefibrillatory interval of chest compression (0 of 8, 0 of 8, 2 of 8, and 7 of 8, respectively, p <.005). Two additional groups then were randomized to receive re...Continue Reading

  • References26
  • Citations27

Mentioned in this Paper

Ventricular Fibrillation
Laboratory Studies
4-isopropyl-3-(methylsulfonyl)benzoyl-guanidine methanesulfonate
Sodium-Hydrogen Antiporter
Basic Cardiac Life Support
Rats, Sprague-Dawley
Anterior Thoracic Region
Growth factor-activatable Na-H exchanger NHE-1

Related Feeds


Arrhythmias are abnormalities in heart rhythms, which can be either too fast or too slow. They can result from abnormalities of the initiation of an impulse or impulse conduction or a combination of both. Here is the latest research on arrhythmias.