Cardiopulmonary resuscitation performed by lay people is finding itself in an unfamiliar and uncomfortable position--questioned by researchers who say it may not improve survival after heart attacks and can sometimes even increase brain damage when the heart has stopped.
And though the number of critics is small so far, some of them contend that much of the money spent to train citizen CPR rescuers would be better used to increase the quick availability of electric heart-jolting machines called defibrillators and to expand paramedic and emergency medical technician programs.
The critics concede citizen CPR occasionally saves some lives, but they argue other victims may be harmed and that CPR's benefits have been greatly exaggerated. (In contrast, favorable studies have found that heart attack victims' chances of survival are up to five times greater with CPR.)
Still other critics say significantly improved response times by professional rescuers could also be turned to advantage by rushing patients to hospitals to undergo open-chest CPR, in which surgeons cut through the ribs and massage the heart itself. Used extensively before development of external CPR, open-chest heart massage has recently been undergoing a resurgence in interest. Even proponents of bystander CPR concede the open-chest procedure is the best technique and agree that quicker response times by paramedics could lead to greater use and more lives saved.
"Would I have it (bystander CPR) done to me if I dropped over? Yes. There's no alternative at the moment," said Dr. Bruce Thompson, formerly of Milwaukee and now on the staff of Henry Ford Hospital in Detroit and one of the researchers who has questioned citizen CPR programs. "I would do it to my wife and to my child, but I would also realize full well that unless the definitive care (defibrillation) to convert to a (viable) rhythm was immediately available, the chances of neurologic survival are virtually nil.
"If you are taking public money (to train people in citizen CPR), you would probably better spend that money on improving access to the system."
It is a controversy in which citizen CPR as a grass-roots, do-it-yourself system touted as capable of saving tens of thousands of lives a year has found itself on profoundly strange turf--in question and even under attack for the first time since a national commission recommended, in 1966, that millions of Americans undergo CPR training.
Since then, the citizen CPR movement has attained a nearly religious fervor, with an estimated 50 million people trained in the belief that the simple steps of CPR can help to bring heart attack, drowning and some accident victims literally back from the dead.
Four million to 5 million people undergo CPR training each year--either for the first time or in refresher courses--according to the American Heart Assn., which shares national responsibility for citizen rescuer training with the American Red Cross. Newly revised guidelines for CPR training--published just last week--say the program's goal is to save 100,000 lives a year nationwide.
The new guidelines pointedly call for major increases in defibrillation availability. This could lead to stationing defibrillators on fire engines, in police cars, in public buildings and many other places where they can be quickly brought into play in an emergency--without waiting for paramedics to arrive.
Since 1984, however, CPR itself has been the subject of a quiet but growing controversy among both emergency medicine specialists and basic science researchers. The battle has been joined and fought almost exclusively within the pages of medical journals and the confines of physician conferences.
A Critical Definition
It is a dispute nowhere near resolution, with CPR's critics contending that in the largest and most thorough study of patient outcomes yet completed, there was no significant difference in survival rates between heart attack victims who had citizen CPR and those who didn't. The definition of "survival" has become crucial, with most experts on both sides of the issue agreeing that the fairest measure now is whether a patient lives to be discharged from the hospital--not just long enough to reach the emergency room while technically not dead.
However, no reliable research design has been developed to collectively measure the degree to which large numbers of heart attack victims whose hearts stopped beating have suffered severe, permanent brain damage--a factor most specialists agree is of growing concern.
CPR's defenders have counterattacked with studies of their own--more numerous than those of the critics--whose data indicate CPR is a major lifesaver. Some of the defenders have branded some of the critics as "irresponsible" for suggesting that the national dedication of resources, manpower and training to CPR may have accomplished little.
Among the principal combatants in the dispute are top physicians in Seattle and Milwaukee--two cities often cited as having the nation's best emergency cardiac care systems. CPR has sustained its major criticism from a research team originally formed at the Medical College of Wisconsin. The Milwaukee team published its most comprehensive survey finding CPR produces survival rates no better than non-CPR cases this month in the Annals of Emergency Medicine, a major journal.
The most vocal defense has come from experts at Seattle's King County Health Department and the University of Washington School of Medicine. CPR has no shortage of believers, however, and the defense has been joined by doctors and other health workers from UCLA to the American Heart Assn.'s national Committee on Emergency Cardiac Care.
The case against reliance on massive citizen CPR programs includes:
- A series of Milwaukee studies that began in 1984. Initially, doctors there examined the outcomes of a series of 421 patients who suffered from a potentially lethal interruption in their heart rhythms called ventricular fibrillation , in which the heart discontinues its regular beating sequence and its pumping action stops, even though the heart muscle is still capable of recovery. Shocking with a defibrillator can often restore the normal beating sequence.
The study found that patients whose circulation was maintained by professional rescuers using CPR before defibrillation had a significantly higher recovery rate than those who did not receive CPR, but it also found that the recovery rates for victims with no CPR and those who received CPR from a lay CPR rescuer were not statistically different. A total of 26% of the citizen CPR patients were saved, versus 27% of those who did not have CPR.
- In the newest Milwaukee study, the research team carried the project even further, reviewing the outcomes of 1,905 patients who suffered witnessed heart seizures during a 10-year period starting in 1973. The project represents the most thorough single study of CPR ever done. Of 1,248 victims on whom citizen CPR was begun before paramedics arrived, 14.6% survived to be discharged from the hospital. But a nearly identical proportion--15%--of 252 victims who received no CPR also survived to discharge.
CPR was found to have a small--though statistically significant--effect on survival only in patients suffering from a severe form of heart seizure with an overall mortality rate of 95%.
"The current dogma that bystander CPR is primarily responsible for increased save rates in prehospital arrest needs to be challenged," the Milwaukee team concluded. CPR's defenders contend that Milwaukee, which in recent years has developed a system in which the average heart attack response time for paramedics is just 2.2 minutes is so atypical of the rest of the country that the role of CPR in Milwaukee is simply not representative of its potential value elsewhere.
- Between 1984 and April of this year, a handful of laboratory researchers, principally at Michigan State University, have reported results of a half dozen different studies on the physiologic effects of CPR in animals--primarily dogs, which are used for training surgeons because their anatomies are generally similar to those of human beings. The laboratory studies have suggested that, unless CPR is begun immediately after a heart attack victim is stricken, CPR may actually exacerbate brain damage because small volumes of blood that might gravitate to the brain may be kept in the chest cavity by vigorous chest compressions characteristic of CPR.
The value of CPR in general in maintaining oxygen supply to the brain has also come into doubt and researchers have questioned whether, in the absence of arrival of professional rescuers within four to six minutes after an attack, a victim may be technically kept alive by CPR but with such massive brain damage that meaningful life may never again be possible.
- Still other researchers have suggested that today's method of bystander CPR may be incapable of providing adequate artificial circulation in many patients and contended that a different system--in which the rescuer pushes, in sequence, on both the chest and the abdomen--may be more useful. Currently, bystander CPR involves alternating between blowing air into the lungs through the mouth and compressing the chest to maintain minimal blood flow to vital organs.
- Yet another review of CPR, dating to 1981, found that in a surprisingly large proportion of cases, CPR can result in severe injury to a victim being resuscitated. CPR resulted in fractures of the ribs or breastbone in more than half of 2,228 cases reviewed in a study by researchers at the Universities of Miami and Florida/Gainesville. Liver rupture was noted in a total of 14 cases and potentially harmful fluid was found in the chest in 46%--though that condition occurs in many heart attacks, irrespective of resuscitation.
Even among the critics, it is difficult to find anyone who will say yet that citizen CPR training in general--most of which is accomplished by private means and requires little public money--represents wasted effort. "I think it would be premature to say that (citizen CPR) programs have been detrimental or have not been worth the effort that has been spent," said Dr. Harlan Stueven, of Milwaukee's Mount Sinai Hospital and a principal researcher in the project there.
"The Red Cross and the American Heart Assn. have done a lot, I believe, to foster an awareness of heart disease and a realization that there are things that can be done for the patient," Stueven said, adding that simply training bystanders to remember the telephone number for emergency medical assistance and to clear the windpipe of a heart attack victim could justify the cost and effort of citizen programs. "But the implication is that CPR is the thing that's going to save the victim. That isn't true."
Countering these findings, the defense of CPR has offered these pieces of evidence:
- In a 1985 review of CPR research, Seattle physicians found nine studies conducted in five states in the U.S. and three other countries in which CPR reportedly resulted in rates of survival including hospital discharge that were as much as five times greater for victims who had CPR than for those who did not.
The study, by doctors at the University of Washington School of Medicine, concluded that, particularly in cities where paramedic response times are less than ideal, citizen CPR can often maintain minimal circulation during the critical wait for professional help. The study, published in the Journal of the American Medical Assn., also concluded that improved CPR techniques must be developed that can provide greater blood flow.
"In the meantime, any attack on CPR as dangerous or ineffective, or recommendations to abandon programs that train citizens in CPR, can only be considered irresponsible," the study concluded. "These efforts (CPR programs) do no harm and clearly save lives."
The Seattle review, however, was faulted by the Milwaukee critics because, they said, the research on which it was based did not assess the contribution of CPR alone to survival rates, as compared to other treatments given the patients, including defibrillation. None of the studies in the review was as large or as long-term as the new Milwaukee research project.
More important, perhaps, the earlier inquiries were unable to verify that the people who survived after receiving citizen CPR actually had undergone heart and respiratory arrest before passers-by began working on them. Doubts about whether citizen CPR is performed on people who have actually had heart attacks, or whether they may simply have fainted or fallen, have plagued grassroots rescue programs for years.
Dr. Richard O. Cummins, one of the two authors of the Seattle analysis, agreed there is no question that electrical defibrillation is the treatment that eventually spells the difference between death and survival for many heart attack victims, but he said CPR continues to play a key role. "I think it's vital to make sure people have the perspective that what actually resuscitates a person in 90% of cases is electricity and not CPR," he said. "What we're really talking about is what do you do while you're waiting for the electricity? If there is any kind of debate in terms of the CPR controversy, that, in one sentence, is it.
'The Big Harm'
"I don't think anybody is seriously considering abandoning citizen CPR programs. I think the damage from the Milwaukee data is that it may raise the threshold for starting more citizen CPR programs. People who are thinking about getting one started and recognizing the time, the trouble and the expense, may say, 'Milwaukee says it makes no difference to do it.' To me, that would be the big harm."
- In a 1984 study not included in the Seattle review, Detroit doctors also found a benefit to CPR in terms of survival, concluding that while victims who had citizen CPR beginning five minutes or longer after their heart seizure had no better survival rates than those who didn't (4% to 4.6%), the differences in the two groups were enormous for patients on whom CPR is begun immediately or within two minutes of an attack (21.3% of CPR patients survived versus 4.8% of those who did not have it) and within three to four minutes after the seizure (11.7% for CPR versus 5% without.)
- At UCLA, researchers reviewing patient outcomes in Los Angeles--where a paramedic system considered the model for the nation in the early 1970s has lagged in the 1980s and is now considered mediocre among major cities--found that survival data in locales with superior emergency medical care systems are different from those elsewhere. But even with comparatively poor response times in Los Angeles, the UCLA team concluded in a study published in 1983 that citizen CPR resulted in a local advantage in survival of four times that of victims who did not have CPR.
"Our results show that some survival benefits have been achieved from these (citizen CPR) programs, but further research will be needed to determine how the additional survival benefits achieved in Seattle can be accomplished in larger cities, such as Los Angeles," the UCLA researchers concluded.
Dr. Peter Guzy, who headed the UCLA study said that, while he has not continued in CPR research, he remains convinced of CPR's value. "I don't have any different opinion now than I did then," Guzy said.
Dr. James Niemann, an associate professor of medicine at UCLA and associate chairman of the emergency medicine department at Harbor-UCLA Medical Center who has followed the dispute over CPR, said he has examined all of the data involved and concluded that "there is not as much of a controversy here as they (the Milwaukee experts) think (there) is."
"I personally think that citizen CPR saves lives and, although I don't have any strong data to (prove) that, there is nothing in the literature to suggest otherwise," said Niemann, who was not involved in the 1983 UCLA study. "The critical component is the relationship between citizen CPR and advanced response. The earlier somebody arrives with a defibrillator, the better."
Superior Response Time
Dr. William Montgomery, chairman of the heart association's national cardiac care committee and an associate professor of anesthesiology at the University of Hawaii School of Medicine, said he believes the results described by the Milwaukee experts can be explained by the superior response times recorded for paramedic units there. "There has been some question about the effect of bystander CPR and there has been the dispute, if you can call it that, between the people in Seattle and Milwaukee," Montgomery said in a telephone interview.
"You have to remember that people taking CPR classes are getting many other benefits . . . learning to recognize the symptoms and signs of a heart attack. Learning to remember their local emergency phone number. This (alone) allows early entry into the emergency medical system and certainly saves some number of lives.
"Clearly, we need more data in this whole field . . . because the data we have to make many of our decisions (on) is sound, but there's not much of it."