At the grocery store a man starts grabbing at his chest and breathing very fast. He falls to the ground. A bystander begins performing CPR until the paramedics arrive. That stranger simply thought she was being kind—she had no idea that her intervention made a difference. Two new studies find that bystander intervention causes higher survival rates for people who experience out-of-hospital cardiac arrest.
According to the American Heart Association, 359,400 Americans experience out-of-hospital cardiac arrest in 2013, the last year for which there are statistics. Cardiac arrest is the loss of heart function, usually due to a fast erratic heart rhythm (ventricular fibrillation), which stops blood flow to the body. This is a life threatening medical emergency for people and many experience a poor outcome. The overall survivor rate for people experiencing out-of-hospital cardiac arrest for 2013 is dismal and was approximately 10%. Superior survival rates are noted among patients experiencing cardiac arrest within the hospital; but even in this circumstance, only ¼ survive. Prior efforts at improving survival following out of hospital cardiac arrest have not met with significant success. In this context, two recent studies published in “JAMA” show that increased and prompt bystander interventions, including initiation of cardiopulmonary resuscitation, aka CPR, and utilization of automated external defibrillators, in addition to first responder interventions, led to much higher observed survival rates.
“Following cardiac arrest, there is an abrupt cessation of blood flow to vital organs of the body,” says Venu Menon, MD, staff cardiologist in the Section of Cardiovascular Imaging and Director of the Coronary Care Unit in the Robert and Suzanne Tomsich Department of Cardiovascular Medicine. “As a result, when the EMS arrives on the scene and performs defibrillation, the likelihood of surviving the arrest neurologically intact increases.” Dr. Menon was not involved in the recently reported studies.
Researchers at Kanagawa University of Human Services in Yokosuka, Japan looked at the relationship between bystander intervention and neurological changes in survivors. Nakahara and his colleagues looked at 167,912 patients who experienced out-of-hospital cardiac arrest who received bystander intervention from January 2005 to December 2012. Active public participation increased favorable neurological outcomes from 3.3 % to 8.2%. The researchers found an association between initiation of bystander chest compressions and defibrillation and favorable neurological outcomes.
The second study evaluated 4,961 people who suffered out-of-hospital cardiac arrest from 2010 to 2013. Researchers at Duke University examined outcomes of intervention, including chest compression and defibrillation. Bystander intervention increased positive neurological outcomes from 7.1% to 9.7%. When bystanders intervened, overall survival rates increased from 15.2 % to 33.6%.
“Bystander-initiated CPR was associated with greater likelihood of survival with favorable neurological outcome,” the researchers wrote in the paper.
While the gain might seem slight, any improvement in outcomes will have an important impact on people’s lives. Both studies included an interesting finding—the number of people intervening in cardiac arrest situations has increased overtime suggesting increased public participation with this medical emergency.
The Duke study notes that the increase of bystander intervention coincided with a statewide educational campaign on resuscitation training. This, along with the primary findings from both studies, underlies the importance of people learning CPR and other interventional techniques.
“We should continue to encourage and also educate our public, so that more and more bystander CPR is done,” said Dr. Menon.
If you see someone lose consciousness and there is no pulse – Call 911 and begin CPR. Chest compresions are all it takes – press hard and fast in the center of the chest. The American Heart Association offers instruction on their website and states, “Press to the beat of Staying Alive until Help Arrives.”