The changes in the 2017 American Heart Association Focused Updates on Adult and Pediatric Basic Life Support and Cardiopulmonary Resuscitation Quality also re-emphasize the importance of bystanders starting immediate chest compressions if they see an adult collapse in a suspected cardiac arrest. Immediate bystander help has been shown to double or triple survival chances among the more than 350,000 Americans who suffer out-of-hospital cardiac arrest each year.