Author Affiliations: Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland (Dr Weisfeldt); and Department of Emergency Medicine, Virginia Commonwealth University, Richmond, Virginia (Dr Ornato).
Cardiac resuscitation after cardiac arrest or ventricular fibrillation has been limited by the need for open thoracotomy and direct cardiac massage. As a result of exhaustive animal experimentation a method of external transthoracic cardiac massage has been developed. Immediate resuscitative measures can now be initiated to give not only mouth-to-nose artificial respiration but also adequate cardiac massage without thoracotomy. The use of this technique on 20 patients has given an over-all permanent survival rate of 70%. Anyone, anywhere, can now initiate cardiac resuscitative procedures. All that is needed are two hands.
See PDF for full text of the original JAMA article.
Few medical publications have such practical, long-lasting importance that they affect the lives, careers, and life-saving skills of virtually all health care professionals. “Closed-Chest Cardiac Massage” by Kouwenhoven and colleagues1 is such a work because it described a breakthrough resuscitation technique that could be applied by any trained individual without special equipment and has saved the lives of countless cardiac arrest patients. Sladen2 provided remarkable details and vignettes of the initiation of cardiopulmonary resuscitation (CPR) at Johns Hopkins Hospital at the time of the first republication of this article in the 100-year anniversary issue of JAMA in 1984.
Ask any health care professional and he or she will readily describe a resuscitation “save” that was especially memorable. For example, in 1967, one of us (M.L.W.) was a medical resident sent with other residents to respond to a cardiac arrest call in the eighth-floor elevator of the medical school building adjacent to the hospital in which we were working. The patient, pulseless and apneic, was a well-dressed man who turned out to be a new department chairman on his first day at work. We frantically began applying the relatively new technique of closed-chest massage described by Kouwenhoven et al1 just a few years previously and transported the patient to the emergency department on a seemingly endless trek down the elevator and through numerous corridors. After approximately 30 minutes of failed resuscitation, the chief resident was ready to pronounce the patient as dead, but we pleaded and continued resuscitation attempts for another 10 minutes. Much to our delight (and surprise), resuscitation was successful and the patient survived neurologically intact. Within 1 month, the medical center's newest department chairman was back at work, greeting his residents daily in the lunch room.
The effectiveness of chest compressions was unequivocal in this case and in an untold number of similar cases of patients who received a second chance at life after receiving closed-chest compression, often in conjunction with artificial respiration, defibrillation, and other forms of advanced life support and postresuscitation care. However, such cases represent the exception to the rule, since to this day, almost 50 years after publication of this landmark article,1 only a minority of cardiac arrest patients survive to hospital discharge neurologically intact. This is true whether the cardiac arrest occurs in the hospital,3 where the survival rate averages 17%, or out of the hospital,4,5 where survival in most communities is only 2% to 6%, when all cardiac arrest events, not only the most treatable cases (eg, witnessed arrest, bystander performed CPR, initial rhythm ventricular fibrillation, and bystander use of an automated external defibrillator in a public setting accounting for less than 20% of the total), are used as the denominator for analysis. But the exceptional cases that result in neurologically intact survival are notable because they provide confirmation of what is needed in a comprehensive treatment strategy that (1) optimizes blood flow and oxygen delivery to vital organs during resuscitation; (2) minimizes the time it takes to restore effective spontaneous circulation; and (3) maximizes neurological and other vital organ recovery postresuscitation.
For almost 2 decades, the American Heart Association's (AHA’s) chain of survival strategy (early access, early CPR, early defibrillation, and early advanced care) has served as the organizational framework for educating and organizing health care professionals, public safety workers, and laypersons into effective in-hospital and out-of-hospital resuscitation systems.5 Most recently, a fifth link—postresuscitation care—has been proposed to acknowledge its ability to enhance neurologically intact survival. Substantial progress has been made in each of these areas but challenges remain.
When Kouwenhoven et al1 published their article, there were no in-hospital code teams, no organized emergency medical services systems (emergency medical technicians did not appear until the late 1960s/early 1970s), and no universal emergency telephone number (ie, 911). Nearly all of the geographic United States now have 911 service and recently, technology has enabled direct routing of calls placed by cell phones to the nearest 911 public safety answering point with automatic triangulation of the caller's approximate location. The great challenge that remains is to develop effective strategies or technologies that can reduce the large percentage of cardiac arrests that are currently unwitnessed (out of hospital, approximately 50%)6 or unwitnessed/unmonitored (in hospital, 14%).3 Many hospitals are now dispatching medical emergency teams that can provide high-risk patients with early access to stabilizing interventions with a goal of preventing decompensation into cardiac arrest.
Kouwenhoven et al1 could hardly have imagined a time in which millions of health care workers, public safety personnel, and laypersons knew how to perform CPR as a result of the tireless efforts of organizations such as the AHA and the American Red Cross. Decades of research have proven that closed-chest massage generates blood flow by both direct cardiac compression (cardiac pump as assumed by Kouwenhoven et al1) as well as cyclic changes in intrathoracic pressure (thoracic pump).7
Weisfeldt and Becker8 theorized that there are 3 physiological phases of resuscitation: electrical, circulatory, and metabolic. When cardiac arrest occurs due to ventricular fibrillation (VF), myocardial adenosine triphosphate (ATP) levels begin to decline as fibrillating myocardial cells continue to consume ATP at a nearly normal rate. During the electrical phase (first few minutes), prompt defibrillation is often the only effort that is required to restore circulation. Myocardial ATP stores soon decrease to a critical level, at which point a defibrillation shock will usually terminate VF only to result in either asystole or pulseless electrical activity as cells run out of high-energy phosphate “fuel.” During this circulatory phase, a brief period (90 seconds to 3 minutes) of effective chest compression prior to defibrillation can boost myocardial ATP supplies and increase the likelihood that a perfusing rhythm will result after a defibrillation shock. If the patient remains in cardiac arrest for longer than 8 to 10 minutes, increasing cellular ischemic injury develops during the metabolic phase of resuscitation, which indicates that additional cellular protective measures will likely be needed to restore vital organ function. Thus, the strategic approach for resuscitating individuals with cardiac arrest and VF has evolved from “shock first and often” to a time-critical sequence of high-quality CPR, defibrillation, and postresuscitation care.
This new strategy highlights the importance of high-quality, minimally interrupted CPR to maximize tissue oxygen delivery and intracellular high-energy phosphate levels. Conventional closed-chest CPR is at best a holding action, providing hemodynamic changes similar to those seen in cardiogenic shock, with low systemic arterial pressure, markedly reduced cardiac output, and high left ventricular filling pressure. The quality of CPR (including factors such as the adequate depth, force, and duration of chest compression; complete chest wall decompression during the upstroke; minimally interrupted chest compression at a rate of approximately 100 per minute; and avoidance of hyperventilation) is a critically important determinant of neurologically intact survival.9 The latest AHA guidelines for CPR and emergency cardiovascular care emphasize the renewed importance of high-quality CPR and have simplified the technique to enable easier learning and better rescuer skill retention.10 Several communities have recently documented significant improvement in out-of-hospital cardiac arrest survival after implementation of the latest CPR guidelines and principles.11
A ventricular tachyarrhythmia is the initiating event in more than 80% of patients who develop out-of-hospital primary cardiac arrest during ambulatory electrocardiographic monitoring,12 and survival declines rapidly if defibrillation is not performed in the first few minutes. As a result, VF is the presenting rhythm in only 22% to 35% of out-of-hospital cardiac arrest cases when emergency medical services personnel arrive.13 A notable exception is for witnessed cardiac arrests that occur in public areas such as busy airport terminals, casinos, malls, and large sporting events. In such settings, there is a high prevalence of initial VF and an approximate doubling of survival when lay rescuers rapidly attach and use an automated external defibrillator.14
Although laboratory studies suggest benefit from use of adrenergic vasoconstrictors during CPR and antiarrhythmic medication for VF cases, no large-scale, randomized, placebo-controlled trials have been conducted that can conclusively define the value of these agents during resuscitation. The AHA includes these agents in its CPR guidelines based on their historical use, experimental evidence, and limited human trial experience.
Increasing evidence suggests that metabolic interventions administered postresuscitation, particularly a moderate degree of induced hypothermia sustained for 24 to 48 hours, can improve overall survival and neurological outcome for out-of-hospital cardiac arrest patients with an initial rhythm of VF, although there is less certainty about the benefit in patients with other initial rhythms.15 In addition, goal-directed, protocol-driven, postresuscitation care can significantly improve the odds of neurologically intact survival to hospital discharge.
A great deal of progress has been made in resuscitation since the classic publication by Keuwenhoven et al,1 and the acquisition of new knowledge and techniques is accelerating. The National Heart, Lung, and Blood Institute has recently created a large, multicenter, resuscitation clinical trials network (Resuscitation Outcomes Consortium [ROC]) in partnership with the Institute of Circulatory and Respiratory Health of the Canadian Institutes of Health Research and other government and nongovernment funding partners. A primary goal of ROC is to provide an efficient community laboratory that can speed the testing and translation of promising resuscitation techniques into everyday, life-saving clinical practice. In addition, 2 large prospective US resuscitation registries (the National Registry of CPR for in-hospital and the ROC Epistry for out-of-hospital cardiac arrest cases) now exist with financial support from the AHA. Each of these registries is generating solid epidemiological data, helping to track progress in striving to make survival from cardiac arrest the rule and not the exception.
Corresponding Author: Myron L. Weisfeldt, MD, William Osler Professor of Medicine, Director, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287 (email@example.com).
Financial Disclosures: Dr Weisfeldt reports serving as study chair, National Institutes of Health (NIH) Resuscitation Outcomes Consortium (ROC); and Dr Ornato reports serving as science advisory board member, ZOLL Scientific, and as cardiac co-chair, NIH ROC.
Weisfeldt ML, Ornato JP. Closed-Chest Cardiac Massage: Progress Measured by the Exceptions. JAMA. 2008;300(13):1582-1584. doi:10.1001/jama.300.13.1582