The University of Washington School of Public Health contributed to a major new study of emergency medical responses at the scene of adult cardiac arrests not caused by trauma.
The research is the largest randomized trial ever conducted in patients with cardiac arrest – it involved 114 emergency medical services agencies across the United States and Canada and nearly 24,000 out-of-hospital adult cardiac arrest patients. The patients were assigned to standard CPR with continuous chest compressions or to a CPR technique where chest compressions are interrupted to perform rescue breathing.
The results were published in the New England Journal of Medicine and presented November 9 at the American Heart Association Scientific Sessions in Orlando, Florida.
From earlier studies, emergency medical services staff and researchers were concerned that CPR methods that alternate chest pumps with a few lung inflations might reduce blood flow and possible survival.
“The results of this study may well change emergency medical services CPR practice,” said lead author Dr. Graham Nichol, University of Washington professor of medicine and director of the UW Medicine Center for Prehospital Emergency Care. “Both groups did well. But it appears that patients treated by EMS providers who interrupted chest compressions to deliver rescue breathing using a bag mask appear to survive a bit more often.”
Dr. Nichol emphasized that this particular study evaluated CPR by emergency medical services providers at the scene and during transport to the hospital, not bystander CPR. Bystanders assisting at the scene of a cardiac arrest generally perform continuous chest compressions without rescue breathing. Dr. Nichol added that researchers will continue to analyze the data gathered during the emergency medical services CPR study.
Co-authors included Dr. Susanne May, associate professor of biostatistics and Dr. Brian Leroux, professor of biostatistics. Dr. May directs the Resuscitation Outcomes Consortium coordinating center, based at the University of Washington School of Public Health, which coordinated data for this trial.