ABC and its variations are initialism mnemonics for essential steps used by both medical professionals and lay persons (such as first aiders) when dealing with a patient. In its original form it stands for Airway, Breathing and Circulation.  The protocol was originally developed as a memory aid for rescuers performing cardiopulmonary resuscitation, and the most widely known use of the initialism is in the care of the unconscious or unresponsive patient, although it is also used as a reminder of the priorities for assessment and treatment of patients in many acute medical and trauma situations, from first-aid to hospital medical treatment.
ABC (and extensions of this initialism) is a mnemonic for memorizing essential steps in dealing with an unconscious or unresponsive patient. It stands for Airway, Breathing, and Circulation. Some protocols add additional steps, such as an optional "D" step for Disability or Defibrillation. It is a reminder of the priorities for assessment and treatment of many acute medical situations—from first-aid to hospital medical treatment.
Troels Thim1,2, Niels Henrik Vinther Krarup1,4, Erik Lerkevang Grove1, Claus Valter Rohde3, Bo Løfgren1,41Department of Cardiology, Aarhus University Hospital, Aarhus, 2Department of Internal Medicine, Regional Hospital of Randers, Randers, 3Department of Anestesiology, Aarhus University Hospital, Aarhus, 4Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, DenmarkAbstract: The Airway, Breathing, Circulation.