NEW YORK (Reuters Health) – More Americans hospitalized for cardiac arrest are surviving now compared with a decade ago, a new study finds.
Researchers are not sure of the reasons for the improvement. But they suspect it’s changes in how hospitals treat cardiac arrest, and possibly the way bystanders respond when they see someone suddenly collapse.
The study, which appears in Circulation online June 27, found that in 2009, the death rate among Americans hospitalized after cardiac arrest was just under 58%. That was down from almost 70% in 2001.
Researchers based their findings on a national hospital discharge database that included nearly 1.2 million Americans who were hospitalized for cardiac arrest. They stress that the numbers account only for cardiac arrest victims who survive long enough to be admitted to the hospital.
Many people die before ever reaching the hospital. And in fact, of the more than 300,000 Americans who go into cardiac arrest outside of a hospital each year, less than 8% survive.
“So this does not say anything about the rates of mortality of all (cardiac arrest) resuscitation attempts,” senior researcher Dr. Alejandro A. Rabinstein, of the Mayo Clinic in Rochester, Minnesota, said in an email.
“But the study does have a clear message,” Rabinstein said. “If you have a cardiac arrest and you get to be hospitalized, your chances of surviving the hospitalization are getting better.”
Since 2001, a few advances have been made in treating cardiac arrest, Dr. Rabinstein’s team says.
One is that experts now recommend that bystanders do “hands-only” CPR. It’s believed to be easier for laypeople to perform, and may have made more people willing to perform CPR on a stranger.
Some research has suggested that the switch to hands-only has helped cardiac arrest survival inch up. The public also has more access to devices called automated external defibrillators (AEDs). It’s possible, Dr. Rabinstein said, that those steps have helped.
But even if cardiac arrest victims get to the hospital alive, they are not out of the woods.
In recent years, doctors have started doing angioplasty in certain patients soon after they arrive at the hospital. And Dr. Rabinstein said he thinks that may be helping.
COOLING TO THE RESCUE?
He also suspects therapeutic hypothermia could be involved. Therapeutic hypothermia helps protect the brain and research suggests it allows more people to survive with their brain function intact.
The rising survival rate in this study came at the same time hospitals starting using therapeutic hypothermia.
“The effect of therapeutic hypothermia is mainly improving survival with (brain) function, rather than survival itself,” Dr. Rabinstein said.
But he added that there is some evidence the therapy is boosting overall long-term survival as well.
Still, the researchers point out, U.S. hospitals have been fairly slow to adopt therapeutic hypothermia. So it’s hard to know how much of an impact the therapy might be having on the national level.