Chicago, IL - A editorial in the January 19, 2005 issue of the Journal of the American Medical Association says CPR guidelines are ripe for a major overhaul and that the key to saving lives may be simplification of the way CPR is currently taught.[1] The editorial, by Drs Arthur B Sanders and Gordon A Ewy, also takes aim at aspects of existing guidelines that they say have been "grandfathered" in, without being subject to the same evidence-based approaches being applied to updates to the guidelines.

"We should be subjecting everything, even the things we've been recommending for 20 or 30 years, to the same level of scrutiny and then make our best consensus decision as to what we should be doing," Sanders told heartwire.

CPR by health professionals Sanders and Ewy's editorial accompanies the publication of two studies examining the quality of CPR by health professionals, one in the hospital setting and one outside of the hospital setting. In both, researchers found that the application of CPR was "inconsistent" and did not meet published recommendations. Both studies used cardiac monitor/defibrillators capable of monitoring chest compressions via a sternal pad and ventilations by changes in thoracic impedance between the defibrillator pads. As Sanders emphasized to heartwire, the two new studies are unique in that previous studies of CPR have used mannequins or outside observers to assess CPR delivery. We should be subjecting everything, even the things we've been recommending for 20 or 20 years, to the same level of scrutiny. In one of the studies, Dr Lars Wik (University Hospital, Oslo, Norway) and colleagues measured out-of-hospital CPR performed by paramedics or nurse anesthetists on 176 patients in Norway, Sweden, and the UK.[2] (In Stockholm, the second rescue vehicle called out to emergencies includes a nurse anesthetist.) They report that chest compressions met or surpassed the recommended rate but were given less than half of the available time during resuscitation events, despite the fact that animal and human studies have suggested that chest compressions may be "the most important factor" in improving chances of survival. In addition, chest compressions were too shallow most of the time (a mean depth of 34 mm), with only 28% of compressions reaching the recommended depth of 38 mm to 51 mm. In the second paper, Dr Benjamin S Abella (University of Chicago Hospitals, IL) and colleagues used the same accelerometers and pressure sensors as Wik's group, fitted onto a defibrillator, to assess CPR delivery in 67 patients who experienced cardiac arrest while in the hospital.[3] As Abella et al report, more than half the cardiac arrests occurred in intensive-care settings, with most of the remainder occurring in general wards. As with Wik et al's study, chest-compression duration and compression depth were both lower than specified in CPR guidelines. In Abella et al's study, chest compressions were not performed 24% of the time during resuscitation and were performed at a suboptimal rate in almost one third of the patients. Ventilation rates were also too high, they add. "In this study of in-hospital cardiac arrest, the quality of multiple parameters of CPR was inconsistent and often did not meet published guideline recommendations, even when performed by well-trained hospital staff," Abella and colleagues concluded. -SW

Speaking to heartwire, Sanders explained that the studies by Wik's and Abella's groups complement a series of studies on CPR education over the past 10 years, showing that it is difficult to retain CPR skills over time.

"The traditional response is, well, we need to recertify more often, we need to teach better, we have to do things to help people retain these skills. And I think that the approach needs to be, rather than doing those things, we need to simplify the process and be more realistic about what we're asking people to do, because people are telling us that they're just not able to do these things," Sanders said.

One of the major findings in both Wik's and Abella's papers, he notes, is that people were not able to perform compressions as consistently as required. "These studies suggest that from a quarter to half of the time that healthcare professionals are doing CPR, they're not delivering chest compressions. They weren't sitting around and not trying to resuscitate the patient, they were doing other things like checking pulses and ventilating. They perhaps don't realize that the chest compressions are very important," Sanders told heartwire.

Data from experimental models and some human studies indicate that if an adequate number of chest compressions, at least 80 per minute, are not delivered, the prognosis is worse for resuscitation, he added.

"So we need to get at a simplified resuscitation procedure that people will remember and be able to deliver," Sanders said.

A separate issue, he notes, is the big push toward making CPR guidelines more evidence-based, particularly as technologies have evolved to help objectively measure particular aspects of CPR delivery. "This would mean we'd have to do randomized controlled trials looking at different compression/ventilation ratios and at other things that we recommend now or at alternative recommendations," Sanders said. "That is fine, except that a lot of the things that we have been doing in the past never passed those same standards. For example, the 15:2 compression/ventilation ratio. People tend to think, well, let's keep this the same because we don't have evidence that another ratio is better."

We need to get at a simplified resuscitation procedure that people will remember and be able to deliver.

The problem, he points out, is that CPR is a very difficult area in which to do research, requiring, among other things, large databases and informed consent. "So we need to look at all the evidence and maybe reevaluate. In our editorial, we recommend that we should not, perhaps, be 'grandfathering' the old standards into the new guidelines and saying that the standards shouldn't change unless we have good studies to change them. Maybe we just need to look at all the studies that have already been done and say, for example, what is the best compression/ventilation ratio?"

Sanders and Ewy will be making their call for simplified guidelines at meetings convened by the American Heart Association and International Liaison Committee on Resuscitation, beginning within the next few weeks. The product of the meetings—the Consensus on Science and Treatment Guidelines 2005—should be published in late autumn. The previous set of guidelines was published in 2000.[4]