Cardiac arrest survival improving in U.S. hospitals: study
More people hospitalized for cardiac arrest are surviving compared with a decade ago, according to a U.S. study, possibly because of changes in hospital treatment and the way bystanders respond when somebody collapses.
The study, which appeared in the journal Circulation, found that in 2008, the death rate among U.S. residents hospitalized after cardiac arrest was just under 58 percent - down from almost 70 percent in 2001.
Researchers, led by Alejandro Rabinstein of the Mayo Clinic in Rochester, Minnesota, based their findings on a national hospital discharge database that included nearly 1.2 million people hospitalized for cardiac arrest.
They stressed that the numbers accounted only for cardiac arrest victims who survive long enough to be admitted to the hospital. Many people die before then.
“This does not say anything about the rates of mortality of all (cardiac arrest) resuscitation attempts,” Rabinstein said in an email. “But the study does have a clear message. If you have a cardiac arrest and you get to be hospitalized, your chances of surviving the hospitalization are getting better.”
Cardiac arrest occurs when a problem in the heart’s electrical activity causes it to stop beating normally, making it unable to pump blood to the body. It’s fatal within minutes unless the normal rhythm can be restored with a shock from a defibrillator.
But since 2001, a few advances have been made in treating cardiac arrest, Rabinstein’s team said.
Sudden cardiac arrest is the sudden, unexpected loss of heart function, breathing and consciousness. Sudden cardiac arrest usually results from an electrical disturbance in your heart that disrupts its pumping action, stopping blood flow to the rest of your body.
Sudden cardiac arrest is different from a heart attack, which occurs when blood flow to a portion of the heart is blocked. However, a heart attack can sometimes trigger an electrical disturbance that leads to sudden cardiac arrest.
Sudden cardiac arrest is a medical emergency. If not treated immediately, it causes sudden cardiac death. With fast, appropriate medical care, survival is possible. Administering Cardiopulmonary resuscitation (CPR) - or even just rapid compressions to the chest — can improve the chances of survival until emergency personnel arrive.
One is that experts now recommend bystanders do “hands-only” CPR, which means chest compressions alone and no mouth-to-mouth breathing. It’s believed to be easier for laypeople to perform, and may have caused more people to be willing to perform CPR on a stranger.
The public also has more access to devices called automated external defibrillators (AEDs) - portable, layperson-friendly versions of the equipment doctors use to shock an arrested heart.
At hospitals, some things have changed too.
In recent years, doctors have started doing angioplasty in certain patients soon after they arrive, which Rabinstein said he thinks may help.
In addition, patients who remain comatose after cardiac arrest are receiving a new treatment called “therapeutic hypothermia,” and it involves cooling the patient’s body using cold IV saline, cooling blankets or ice packs. A day later, doctors slowly re-warm the patient.
The cooling therapy helps protect the brain, which is often severely damaged by cardiac arrest. Research suggests it allows more people to survive with their brain function intact.
The rising survival rate in the study came at the same time hospitals started using therapeutic hypothermia.
“The effect of therapeutic hypothermia is mainly improving survival with (brain) function, rather than survival itself,” Rabinstein said, though he added that there is some evidence the therapy is improving long-term survival as well.
But the researchers warned that U.S. hospitals have been fairly slow to adopt the treatment, so it’s hard to know how much of an impact it might be having on the national level.
###
###
Post Cardiac-Arrest Mortality is Declining: A Study of the U.S. National Inpatient Sample 2001-2009
Methods and Results - The U.S. mortality rates for hospitalized patients with cardiac arrest were determined using the 2001-2009 U.S. National Inpatient Sample (NIS), a national hospital discharge database. Using the International Classification of Diseases, 9th Revision code 427.5, we identified patients hospitalized in the U.S. with cardiac arrest from 2001-2009. The main outcome measure was in-hospital mortality. A total of 1,190,860 patients were hospitalized with a diagnosis of cardiac arrest in the U.S. from 2001-2009. The in-hospital mortality rate decreased each year from 69.6% in 2001 to 57.8% in 2009. In multivariable analyses, when controlling for age, gender, race, and co-morbidities, earlier year was a strong independent predictor of in-hospital death. The mortality rate declined across all analyzed subgroups, including gender, age, race, and stratification by comorbidity.
Conclusions - The in-hospital mortality rate of patients hospitalized with cardiac arrest in the U.S. decreased by 11.8% from 2001-2009.
Jennifer E. Fugate;
Waleed Brinjikji;
Jay N. Mandrekar;
Harry J. Cloft;
Roger D. White;
Eelco F.M. Wijdicks;
Alejandro A. Rabinstein