Ventilation — In the early moments after a patient collapses, the oxygen levels in the lungs are likely adequate, and the blood is probably well oxygenated. Therefore, at this stage, chest compressions are more important than ventilation[66-68]. Consequently, initiating high-quality chest compressions is the first step to improving oxygen delivery to the tissues (Flowchart 1). This is the basis for the CPR-ECC guidelines recommending the use of the compressions-airway-breathing (C-A-B) approach for cardiac arrest[20]. For the latest version of the AHA BLS algorithm, please see this link: here[13].
For more details, see: Adult Basic Life Support for Healthcare Providers - Up-to-Date