Major Changes in the 2005 AHA Guidelines for CPR and ECC

he emergency cardiovascular care (ECC) scientists in- volved in the 2005 evidence evaluation process and the revision of the 2005 AHA Guidelines for CPR and ECC began and ended the process aware of the limitations of the resuscitation scientific evidence, optimistic about emerging data that documents the benefits of high-quality cardiopul- monary resuscitation (CPR), and determined to make recom- mendations that would increase survival from cardiac arrest and life-threatening emergencies. This editorial summarizes the factors that contributed to the tipping point, the point at which information and discussion either triggered support for major changes in the guidelines or reaffirmed existing recommendations. The scientists critically reviewed the sequence and priori- ties of the steps of CPR to identify those factors with the greatest potential impact on survival. They then developed recommendations to support those interventions that should be performed frequently and well. There was unanimous support for increased emphasis on ensuring that rescuers deliver high-quality CPR: rescuers need to provide an ade- quate number and depth of compressions, allow complete chest recoil after each compression, and minimize interrup- tions in chest compressions. The 2005 AHA Guidelines for CPR and ECC are based on the most comprehensive review of resuscitation literature ever published.1 The evidence evaluation process incorpo- rated the input of 281 international resuscitation experts who evaluated research, topics, and hypotheses over a 36-month period before the 2005 Consensus Conference. The process included structured evidence evaluation, analysis, and docu- mentation of the literature.2 It also included rigorous disclo- sure and management of potential conflicts of interest, a process summarized in two editorials.3,4 The Challenge Cardiopulmonary resuscitation and emergency cardiovascu- lar care is a relatively new field. The epidemiologic data is incomplete, and high-level evidence is insufficient to support many recommendations. Although sudden cardiac arrest (SCA) is responsible for an estimated 250 000 deaths out of