The family that defibrillates together [10/26/2002]

I received my residency training in Seattle in the era when Seattle pioneered the development of community education programs in CPR (cardio-pulmonary resuscitation) and emergency rescue services designed to provide cardiac defibrillation within four minutes of a cardiac arrest. These efforts were organized when research showed that if a person has a cardiac arrest, they have almost a 100 percent chance of survival if they are defibrillated (given a measured electrical shock to the heart) immediately. The survival rate drops to 15-45 percent after 4-5 minutes, and to 5 percent after ten minutes. CPR hoped to maintain oxygen to the heart and brain until defibrillation could be given. These efforts were copied throughout the country over the next several decades.We are on the cusp of another revolution in treatment of cardiac arrest, which still occur in 450,000 unexpected cases annually. Most occur outside hospitals or doctors offices in people with known heart disease, but despite efforts to identify risks factors for heart diseasesuch as hypertension, high cholesterol and smoking, for many people a cardiac arrest is the first sign of heart trouble. If we cannot predict who or when a cardiac arrest is likely to occur by a test, and we cannot hope to have rescue teams on site within four minutes, what can bedone? We can expect to see much more information about having cardiac defibrillators in the community with the hope that non-medical people will use them if they see someone collapse.The October 17, 2002 issue of the New England Journal of Medicine reported on a trial of placing defibrillators at various places around O'Hare International Airport in Chicago. The devices were highly visible, much like fire extinguishers would be. There were instructionsin their use, but no EMTs lurking on every corner. Over a two year period, 21 people in O'Hare had cardiac arrests. Eleven patients were successfully resuscitated by good Samaritans acting voluntarily. In six of these eleven cases, the rescuers had no experience in the use ofautomated defibrillators. Four people did not receive defibrillation within five minutes, and all four died.We are already starting to see automated defibrillators appear in places where there are a lot of people airports, sports arenas, hotels, shopping malls on the assumption that where there are lots of people, some of them are likely to have heart attacks, and someone around might try to help them. But where do most cardiac arrests occur? In the home. Is it practical or safe to have defibrillators in the home? The next decade will answer that question. Manufacturers are already selling them for about $2500. How hard is it to learn to use them? An editorial in the same issue of the journal reported a study of sixth grade students who read the directions and successfully used one in a mock situation within 90 seconds, just 30 seconds longer than emergency medical personnel. Of course, those of us past 50 realize sixth-graders learn more quickly than we do, so we might want to study the directionsahead of time, or else be real nice to the grandchildren and have them over a lot.Are there risks to defibrillating a family member? Does Ozzie need to worry that Harriet might zap him during an afternoon snooze on the couch in front of the football game if he looks a tad bit more inert than usual? So far, they seem remarkably safe. The devices have sophisticated heart rhythm monitoring programs, and they will not deliver a shock unless they detect ventricular fibrillation, the rhythm they are designed to treat. In Chicago, none of the people who collapsed for some other reason than cardiac arrest received a shock when it would have been inappropriate. Then again, with those young people hacking into computer programs and spreading computer viruses around, we might need to be real, real nice to the grandchildren.