Sudden Cardiac Arrest
Sudden cardiac arrest (SCA) is a condition in which the heart suddenly and unexpectedly stops beating. Normally, the heart muscle contracts in a rhythmic fashion at about 60 to 100 beats per minute. If the heart stops, the brain and organs don’t get oxygenated blood and the victim will die within several minutes. This is known as sudden cardiac death (SCD).
The most common cause of SCA is ventricular arrhythmia, a condition in which the electrical signals from the lower chambers of the heart (the main pumping chambers) become disorganized and chaotic. This sets off a rapid, irregular heart beat that interferes with the heart’s ability to get blood and oxygen to the body. Eventually, the heart muscle is unable to keep up and quivers instead of contracting.
According to the Heart Rhythm Society, about 250,000 Americans die each year from sudden cardiac arrest. A major risk factor is undiagnosed coronary artery disease. Other risk factors include: family history of SCA, personal history of heart rhythm disturbances, heart failure, drug abuse or drinking too much alcohol.
The Need for CPR
After SCA, brain death occurs within four to six minutes. The heart can only be restarted by applying an electrical shock to the chest (defibrillation). Many establishments now have automatic external defibrillators (AEDs) that can be used to jump start the heart before emergency personnel arrive. When an AED isn’t available, cardiopulmonary resuscitation (CPR) is recommended. CPR uses chest compressions to maintain blood flow to the heart and brain. When given by someone outside the hospital, it’s called bystander CPR. The technique won’t restart the heart, but it will buy some time for the victim until rescue personnel arrive with a defibrillator.
The American Heart Association reports CPR can double the chance of survival after SCA. But many people either don’t know how to perform CPR or are afraid to step in to help. In fact, only about 31 percent of SCA victims receive bystander CPR. For every minute that defibrillation is delayed, the chance of survival falls by 7 to 10 percent.
Teaching CPR – the Wii™ Way
Learning CPR isn’t hard. Researchers have shown that even children can learn how to properly perform bystander CPR. However, Greg Walcott, M.D., Associate Professor of the School of Medicine at the University of Alabama at Birmingham, says one of the main concerns of bystanders is performing the chest compressions at the correct pace and with the right amount of force and depth.
With funding from the American Heart Association, a group of engineering students at the university have developed a prototype CPR training program using the remote from the Wii™ game system. The Wii remote measures speed and location, and thus, can be used to monitor mock chest compressions during CPR. A metronome is used to guide the pace of the compressions.
The investigators are testing several common items in a home (like slightly deflated beach balls or footballs) to use as a surrogate “mannequin.” They would eventually like to develop a game-like program that could be played on a home computer program to teach CPR technique. The Wii remote would be used in conjunction with the program to assess the quality of the chest compressions and provide feedback to the user. The “teaching” could all be done in the privacy of the home, without the need for an instructor.
The Wii CPR program is still in development, but researchers are hopeful it will be available to download onto a home computer later this year. Walcott also envisions introducing the program in schools so students can tell their parents about the availability of the teaching tool. Potentially, hundreds of thousands of people could be trained to perform CPR. The teaching program could also be used to help those who have already learned CPR refresh their skills.
American Heart Association, http://www.americanheart.org
American Red Cross, http://www.redcross.org
Heart Rhythm Society, http://www.hrsonline.org
National Heart, Lung and Blood Institute, http://www.nhlbi.nih.gov
Sudden Cardiac Arrest Foundation, http://www.sca-aware.org
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