Part 5: Adult Basic Life Support

Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, "Initial Recognition BLS-003A, BLS-003B ").These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article.An appendix of worksheets, applicable to this article, is located at the end of the text.The worksheets are available in PDF format and are open access.• Rescuers should begin CPR if the victim is unresponsive and not breathing (ignoring occasional gasps).Gasping should not prevent initiation of CPR because gasping is not normal breathing, and gasping is a sign of cardiac arrest.• Following initial assessment, rescuers may begin CPR with chest compressions rather than opening the airway and delivering rescue breathing.• All rescuers, trained or not, should provide chest compressions to victims of cardiac arrest.• A strong emphasis on delivering high-quality chest compressions remains essential: rescuers should push hard to a depth of at least 2 inches (or 5 cm) at a rate of at least 100 compressions per minute, allow full chest recoil, and minimize interruptions in chest compressions.• Rescuers trained to provide ventilations use a compressionventilation ratio of 30:2.• For untrained rescuers, EMS dispatchers should provide telephone instruction in chest compression-only CPR. Epidemiology and Recognition of Cardiac ArrestMillions of people die prematurely every year from sudden cardiac arrest (SCA) worldwide, often associated with coronary heart disease.The following section summarizes the burden, risk factors, and potential interventions to reduce the risk. Epidemiology Incidence BLS-014BWhat is the incidence, prevalence, and etiology of cardiopulmonary arrest in-hospital and out-of-hospital? Consensus on ScienceMeasuring the global incidence of cardiac arrest is challenging, because there are many different definitions of patient