Automated external cardioversion defibrillation monitoring in cardiac arrest: a randomized trial

Bakhtiar Ali¹ , Heather Bloom¹^,2 , Emir Veledar² , Dorothy House¹ , Robert Norvel¹ , Samuel C Dudley³ and A Maziar Zafari¹^,2

¹Atlanta Veterans Affairs Medical Center, Decatur, Georgia, USA

²Emory University School of Medicine, Division of Cardiology, Atlanta, Georgia, USA

³University of Illinois at Chicago, Section of Cardiology and the Jesse Brown VA Medical Center, Chicago, Illinois, USA

author email corresponding author email

Trials 2008, 9:36doi:10.1186/1745-6215-9-36


Published:	11 June 2008

Abstract

Background

In-hospital cardiac arrest has a poor prognosis despite active electrocardiography monitoring. The initial rhythm of approximately 25% of in-hospital cardiopulmonary resuscitation (CPR) events is pulseless ventricular tachycardia/ventricular fibrillation (VT/VF). Early defibrillation is an independent predictor of survival in CPR events caused by VT/VF. The automated external cardioverter defibrillator (AECD) is a device attached by pads to the chest wall that monitors, detects, and within seconds, automatically delivers electric countershock to an appropriate tachyarrhythmia.

Study Objectives

• To evaluate safety of AECD monitoring in hospitalized patients.

• To evaluate whether AECDs provide earlier defibrillation than hospital code teams.

Methods

The study is a prospective trial randomizing patients admitted to the telemetry ward to standard CPR (code team) or standard CPR plus AECD monitoring (PowerHeart CRM). The AECD is programmed to deliver one 150 J biphasic shock to patients in sustained VT/VF. Data is collected using the Utstein criteria for cardiac arrest. The primary endpoint is time-to-defibrillation; secondary outcomes include neurological status and survival to discharge, with 3-year follow-up.

Results

To date, 192 patients have been recruited in the time period between 10/10/2006 to 7/20/2007. A total of 3,655 hours of telemetry data have been analyzed in the AECD arm. The AECD has monitored ambulatory telemetry patients in sinus rhythm, sinus tachycardia, supraventricular tachycardia, atrial flutter or fibrillation, with premature ventricular complexes and non-sustained VT without delivery of inappropriate shocks. One patient experienced sustained VT during AECD monitoring, who was successfully defibrillated (17 seconds after meeting programmed criteria). There are no events to report in the control arm. The patient survived the event without neurological complications. During the same time period, mean time to shock for VT/VF cardiac arrest occurring outside the telemetry ward was 230 ± 50 seconds.

Conclusion

AECD monitoring is safe and likely results in earlier defibrillation than standard telemetry monitoring.

Trial Registration

National Institutes of Health registration ID: NCT00382928