April 2nd, 2012
Improved Survival After Non-Shockable Cardiac Arrest with New CPR Guidelines
In recent years, resuscitation guidelines have evolved to emphasize chest compressions. At the same time, a greater proportion of out-of-hospital cardiac arrest (OHCA) cases are now due to “nonshockable” rhythms, defined as asystole and pulseless electrical activity, but the effect of the new guidelines on these type of OHCA cases is unknown.
In a study published in Circulation, Peter J. Kudenchuk and colleagues report on more than 10 years of experience treating nearly 4000 out-of-hospital patients with nonshockable OHCA treated in King County, Washington. Midway through the study period, the new AHA guidelines came into effect. Overall, outcomes were poor throughout the study, but several important measures were significantly improved during the second half of the study:
- 1-year survival: 2.7% in the first half versus 4.9% in the second half (adjusted hazard ratio: 1.85, CI 1.29-2.66)
- Return of spontaneous circulation: 27% versus 34% (HR 1.50, CI 1.29–1.74)
- Discharged from hospital: 4.6% versus 6.8% (HR 1.53, CI 1.14–2.05)
- Favorable neurological outcome: 3.4% versus 5.1 (HR 1.56, CI 1.11–2.18)
“By any measure — such as the return of pulse and circulation or improved brain recovery — we found that implementing the new guidelines in these patients resulted in better outcomes from cardiac arrest,” said Kudenchuk, in an AHA press release. He calculated that 2500 lives could be saved each year in North America by fully implementing the new guidelines.