Science of Cardiopulmonary Resuscitation: Just Scratching the Surface.

C ardiopulmonary resuscitation (CPR) involving external chest compression and positive-pressure ventilation was first described >50 years ago in a landmark publication that launched the fundamental approach to present-day CPR. 1 Since this initial description, modern-day CPR has given rise to initiatives related to CPR research, education and training, advocacy, and industry. These ever-increasing efforts are founded on an appreciation that CPR can positively affect survival from cardiac arrest, a common cause of death in most societies. To be clear, the foundational assertion of CPR's benefit is not derived from multiple, high-quality randomized human trials. Rather, evidence has accumulated from experimental (animal) studies and observational human investigations. CPR possesses many of the epidemiological criteria often cited as the basis for causation: biological plausibility, temporality, and dose response. 2 With regard to the epidemiological trait of consistency , there is not uniform agreement across all investigations regarding the association between CPR and outcome; however , the preponderance of studies observes a beneficial relationship. 3 Moreover, community-specific efforts from around the globe to increase bystander CPR correspond to community improvements in survival. 4–7 Thus, the initial discovery of CPR's clinical benefit has been borne out by strong, albeit imperfect science supporting CPR as an essential link in the chain of survival. The original report, however, belies some of the current-day challenges involving CPR, challenges involving both community implementation related to bystander CPR and scientific discovery related to professional CPR. The original report proclaims that " anyone, anywhere can now initiate cardiac resuscitation procedures, " suggesting that most patients experiencing cardiac arrest could and should receive bystander CPR. Unfortunately, less than half of patients experiencing cardiac arrest receive bystander CPR before the arrival of professional rescuers in most US communities. 3 Fortunately, there are accessible strategies that provide the tools for community-based bystander CPR improvement. Strategies such as telecommunicator CPR provide an efficient approach that can substantially boost bystander CPR rates. 8 Other approaches have incorporated CPR training into the secondary school curriculum, targeted training to high-risk geographies or families, or used smart technology to summon free-ranging volunteers to patients potentially experiencing cardiac arrest 9,10 These strategies compliment the cornerstone of traditional instructor-based CPR training. If these multifaceted approaches provide a roadmap for success, why do communities often struggle to achieve best practices? Explanations can vary, but 1 common theme is the challenge to convene the range of stakeholders required for community implementation. 11 …