Adult Basic Life Support
Adult BLS follows a simple, repeatable sequence. When you find an unresponsive adult, verify the scene is safe, check responsiveness (tap and shout), and simultaneously check breathing and pulse for no more than 10 seconds. If the person is unresponsive and not breathing normally (or only gasping), activate the emergency response system, send for an AED, and begin CPR. Agonal gasps are not normal breathing-a frequent trap is treating gasping as adequate breathing and withholding CPR.
Compressions and Ventilations
For an adult, the compression-to-ventilation ratio is 30:2 for a single rescuer and for two rescuers without an advanced airway. Once an advanced airway is in place, give continuous compressions with 1 breath every 6 seconds (10 breaths/min). Deliver each breath over about 1 second and watch for chest rise. If you are trained and willing, use a pocket mask or bag-mask; if not, provide compression-only CPR.
Special situations and traps
- Opioid overdose: if no normal breathing and no pulse, start CPR; if the person has a pulse but is not breathing adequately, give rescue breaths and consider naloxone per protocol.
- Do not delay compressions to search for a pulse for a long time-limit pulse checks to 10 seconds.
- Recovery position is only for a person who is breathing normally and has a pulse.
- A trap is a stem describing a rescuer who stops CPR to look for a pulse after every cycle-unnecessary and harmful.
Worked example: You find an adult collapsed, unresponsive, with occasional gasps and no detectable pulse after a 10-second check. Correct action: call for help/AED, begin compressions at 100–120/min to at least 2 inches, and give 2 breaths after every 30 compressions.