Two heart rhythm medications given by paramedics to patients who failed defibrillation for out-of-hospital cardiac arrest improved the likelihood of the patient surviving. The study — conducted by the Resuscitation Outcomes Consortium and coordinated by the Clinical Trials Center in the University of Washington School of Public Health — was published in the New England Journal of Medicine.
During a sudden cardiac arrest, the heart suddenly stops beating, and blood stops flowing to the brain or other vital organs. More than 300,000 people are treated for out-of-hospital cardiac arrest each year. Previous studies show that nationally only about 10 percent of people who suffer a cardiac arrest away from a hospital survive. Effective treatments, such as CPR and defibrillation, can greatly increase odds of survival.
“Before this study, doctors didn’t know if these two drugs – amiodarone and lidocaine – offered additional benefit, so their use by paramedics varied,” said Dr. Susanne May, an associate professor of biostatistics and director of the Clinical Trials Center at the UW. The Resuscitation Outcomes Consortium includes clinical research sites across the United States and Canada.
The study randomized 3,026 patients with out-of-hospital cardiac arrest caused by life-threatening heart problems that affect the pumping action of the heart’s lower chambers and that are often resistant to defibrillation treatment. In addition to standard resuscitation, these patients received amiodarone, lidocaine or a saline placebo by rapid injection.
“I’m encouraged by the fact that though seemingly small, the 3 percent to 5 percent increase in survival reported in this trial means 1,800 more lives could potentially be saved each year from cardiac arrest,” said lead author of the study, Dr. Peter Kudenchuk, a UW Medicine cardiac electrophysiologist. “We can and should strive to improve treatments for this all-too-common event. We believe that this study is a significant step in the right direction.”
The study was funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health, American Heart Association, U.S. Army, Canadian Institutes of Health Research and Defense Research, and Development Canada.
Read the paper: http://www.nejm.org/doi/full/10.1056/NEJMoa1514204