Patients With Delayed In-Hospital Defibrillation Have Lower Survival

Armen Hareyan's picture

A study found that delayed defibrillation was associated with lower rates of survival after in-hospital cardiac arrest.

This observational study evaluated data from 369 hospitals with 6,789 patients who suffered cardiac arrests with the first identifiable rhythm being ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) between Jan. 1, 2000 and July 31, 2005. The study used data from the American Heart Association's National Registry of CPR (NRCPR), a database of in-hospital resuscitation events, treatments and outcomes.

Researchers reported that 34.1 percent of patients survived to hospital discharge. Nearly one-third of patients (30.1 percent) received delayed defibrillation, defined as time to defibrillation of greater than 2 minutes, after the arrest began.


Delayed defibrillation was associated with a significantly lower probability of survival to hospital discharge (22.2 percent vs. 39.3 percent when defibrillation was not delayed). Every minute of delay until defibrillation was associated with lower rates of survival to hospital discharge. In addition, patients who survived to hospital discharge but experienced delayed defibrillation were less likely to have no major neurological disability.

The study noted certain hospital-level factors were associated with delayed defibrillation. These included cardiac arrests in small hospitals (

The American Heart Association's 2005 Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care note that early CPR and defibrillation are critical to survival from sudden cardiac arrest.

In hospitals where defibrillation is performed infrequently or where staff isn't trained to use a manual defibrillator, the American Heart Association recommends using an automated external defibrillator (AED) to help deliver early defibrillation and recommends that hospitals develop a comprehensive program for AED use that includes identifying and training likely responders and performing device maintenance.