AHA BLS Provider key terms

The sequence of actions that gives a person in cardiac arrest the best chance of survival, from recognizing the emergency and starting CPR through defibrillation, advanced care, and recovery support.

Chest compressions delivered at the correct rate, depth, and recoil with minimal interruptions, combined with effective breaths, so blood keeps circulating to the brain and heart.

The speed of chest compressions, which for both adults and children should be 100 to 120 per minute, roughly two compressions every second.

How far the chest is pushed down during compressions: at least 2 inches (5 cm) for adults and about one third of chest depth for children and infants.

Allowing the chest to fully spring back between compressions so the heart can refill with blood; leaning on the chest between pushes reduces blood flow.

The proportion of resuscitation time during which compressions are actually being performed; it should be at least 60 percent, so pauses are kept short.

Irregular, gasping, or snoring-like breaths sometimes seen in the first minutes of cardiac arrest; they are not normal breathing and mean CPR should begin.

A condition in which the heart stops pumping effectively, so the person is unresponsive, not breathing normally, and has no pulse; immediate CPR and defibrillation are needed.

A state in which a person does not respond to voice or touch; in BLS this triggers a check for breathing and pulse and, if absent, starting resuscitation.

A brief assessment of circulation, usually at the carotid artery in adults and the brachial artery in infants, taking no more than 10 seconds to decide whether compressions are needed.

The pulse felt on the inner upper arm of an infant; it is the preferred site for checking circulation in infants younger than 1 year.

The step-by-step response for an adult: verify scene safety, check responsiveness and breathing, call for help and an AED, begin compressions, and attach the defibrillator as soon as possible.

Calling emergency services or activating the facility response team, ideally by a second rescuer, while another rescuer begins CPR and retrieves an AED.

Compression-only CPR without rescue breaths, recommended for untrained bystanders or when a barrier device is unavailable, performed at 100 to 120 compressions per minute.

Breaths given to a person who is not breathing adequately, delivered over about 1 second each and just enough to make the chest rise visibly.

A maneuver that opens the airway by tilting the head back and lifting the chin, used when no head or neck injury is suspected.

An airway-opening maneuver that moves the lower jaw forward without tilting the head, used when a head, neck, or spinal injury is suspected.

Delivering breaths with a self-inflating bag and mask; it requires a good seal and two rescuers working together for effective ventilation during resuscitation.

Air entering the stomach during ventilation, usually from breaths that are too large or too fast; it increases the risk of vomiting and aspiration.

A portable device that analyzes the heart rhythm and delivers a shock if a shockable rhythm is detected, guiding the rescuer with voice prompts.

Delivery of an electrical shock to stop a chaotic heart rhythm and allow the heart to resume a normal rhythm; it is most effective when done early.

A heart rhythm that an AED can treat with a shock, such as ventricular fibrillation or pulseless ventricular tachycardia.

Positioning of the electrode pads on the bare chest, typically one below the right collarbone and one on the lower left side, following the device's diagrams.

The safety step of ensuring no one is touching the person before a shock is delivered and while the AED analyzes the rhythm.

Resuscitation for children and infants, using the same core steps as adult BLS but with adjusted compression depth, ventilation emphasis, and pulse-check sites.

CPR for a child younger than 1 year, using two fingers or two thumbs encircling the chest for compressions and gentle breaths that make the chest rise.

Providing breaths to a person who has a pulse but is not breathing adequately, at a rate of about one breath every 5 to 6 seconds for adults.

The coordination of rescuers through clear roles, closed-loop communication, and mutual respect so that CPR and defibrillation happen quickly and safely.

A communication style in which the receiver repeats back the order and confirms when it is done, reducing errors during resuscitation.

The rescuer who assigns roles, monitors the quality of CPR, and coordinates the overall response while remaining open to feedback from other team members.

A situation in which a person is unresponsive with slow or absent breathing after opioid use; the response includes opening the airway, giving breaths, and administering naloxone if available.

A medication that reverses the effects of opioids on breathing; it is given when an opioid overdose is suspected, alongside CPR and rescue breathing if needed.

A side-lying position used for a person who is breathing and has a pulse but is unresponsive, helping keep the airway open and reduce aspiration risk.

Checking for hazards such as traffic, fire, or electricity before approaching a victim, so the rescuer does not become a second casualty.

Blockage of the airway by an object, causing coughing, difficulty breathing, or inability to speak; treatment depends on whether the person can still cough forcefully.

Back blows and inward-upward pushes to the abdomen used to relieve severe choking in a responsive adult or child; not used for infants.

Firm blows between the shoulder blades used to clear a severe airway obstruction, given first for infants and combined with thrusts in adults and children.