News:Cardiac arrest during weekends and nights is associated with poor outcomes

February 20, 2008 By Vijayalakshmi Kunadian MBBS MD MRCP [mailto:vkunadian@perfuse.org]

NRCPR performed a retrospective analysis in a very large database of patients (n=86 748) who had cardiac arrest in 507 hospitals within the United States from January 2001 to February 2007. This study was conducted to determine if the survival outcome following a cardiac arrest was different when patients sustained a cardiac arrest during 3 time periods:


 * Day/evening time (7 am to 10.59 pm)
 * Night time (11pm to 6.59 am) and
 * Weekends (11pm Friday to 6.59 am Monday).

This study sponsored by the American Heart Association and NRCPR is published in the latest issue of JAMA (see link below).

The primary outcome of this study consisted of survival to discharge and the secondary endpoints consisted of 24 hour survival and favorable neurological outcomes.

Patients aged 18 years (mean age 69 years) and over were included in the study. In total 58 593 patients had cardiac arrest during day time. Of these, 43 483 had cardiac arrest during weekdays and 15 110 during weekends. During night time, 28 155 patients had cardiac arrest. Of these, 20 365 had cardiac arrest during weekdays and 7 790 during weekends.

The common rhythm during cardiac arrest at night time was asystole in 39.6% of patients and ventricular fibrillation occurred in 19.8% of patients. Survival was significantly reduced among patients who had cardiac arrest during night time (14.7%) compared to those who had it during day time (19.8%), p<0.001. Among 44.7% of patients, circulation returned for >20 minutes during night time compared to 51.1% of patients during day time, p<0.001. Survival to 24 hours following cardiac arrest was noted in 28.9% of patients during night time compared to 35.4% of patients during day time. Patients who had cardiac arrest during day time had better neurological outcome compared to those who had it during night time (15.2% vs. 11%, p<0.001).

Of the patients who had cardiac arrest during day time, there was a difference in survival to discharge among those who had it during week days and during weekends (20.6% vs. 17.4%). This difference was not observed among those who sustained cardiac arrest during night time irrespective of whether it occurred during a weekday or a weekend.

This study demonstrates that the survival outcomes were significantly reduced among those who have cardiac arrest during night time and during weekends. Although the exact reasons for this discrepancy in outcomes during different time periods is unclear, the investigators point out in the article that outcome could be improved during night time and weekends by improving staff performance levels by providing them with enhanced training in cardiopulmonary resuscitation.