ABC — Airway, Breathing, and Circulation

by S. Serkan Sezer MD

ABC stands for Airway, Breathing, and Circulation — the three basic, life-saving checks made on a casualty (an injured or seriously ill person) in an emergency. It’s one of the most important memory aids in first aid and emergency medicine, giving rescuers a clear, ordered list of what to check first when every second counts.

The order is deliberate: it follows the things that will kill a person fastest. A blocked airway can be fatal within minutes, so it’s checked before breathing, which in turn is checked before circulation.

What each letter means

  • A — Airway Is the path for air into the lungs clear? The rescuer checks that nothing — the tongue, vomit, a foreign object — is blocking the airway, and opens it if needed (often by gently tilting the head back and lifting the chin).
  • B — Breathing Is the person actually breathing? The rescuer looks for the chest rising and falling, listens for breath, and feels for air. If breathing has stopped, rescue breaths or CPR may be needed.
  • C — Circulation Is blood moving around the body? The rescuer looks for signs of life and serious bleeding. If the heart isn’t pumping effectively, chest compressions (CPR) are started; heavy bleeding is controlled with pressure.

Why the order matters

The genius of ABC is its simplicity under pressure. In a frightening, chaotic moment, a single short word tells a rescuer exactly what to check and in what order, so that the most immediately deadly problems are dealt with first. Clear an airway, restore breathing, support circulation — in that sequence.

A note on variations

You may come across slightly extended versions. DRABC (or DR ABC) adds two steps at the front:

  • D — Danger → make sure the scene is safe for you and the casualty before approaching.
  • R — Response → check whether the person is conscious and responsive.

Some modern guidelines also use CAB (Circulation first) for certain cardiac-arrest situations, or add a D and E for Disability and Exposure in hospital settings. The exact letters can vary, but the goal is always the same: a quick, ordered check of the things most likely to take a life.

Disclaimer

This content is for general educational purposes only and is not a substitute for proper, hands-on first aid training. Reading about ABC is not the same as being trained to perform it. To act safely and effectively in an emergency, take an accredited first aid or CPR course. In a real emergency, call your local emergency number immediately (such as 112 in Turkey and across Europe, 999 in the UK, or 911 in the US) before or while giving first aid.