Bystanders with training in BLS can perform the first three of the four steps.[4]
The AHA-recommended steps for resuscitation are known as DRS CAB:
Check for Danger
Check for a Response
Send for help
C directs rescuers to perform 30 Compressions to patients who are unresponsive and not breathing normally, followed by 2 rescue breaths
A directs rescuers to open the Airway
B directs rescuers to check Breathing but no need to deliver rescue breaths
D directs rescuers to attach an AED as soon as it is available and follow prompts