ABCs (Airway, Breathing, Circulation)

Definition

ABCs is the mnemonic for Airway, Breathing, and Circulation, the universally accepted ordering principle for emergency assessment and intervention. It directs the nurse to secure a patent airway first, ensure adequate ventilation second, and support circulation third.

Components

• Airway: Assess for obstruction (stridor, gurgling), position the airway (head-tilt/chin-lift or jaw-thrust if trauma suspected), and suction or intubate as indicated.
• Breathing: Evaluate rate, depth, symmetry, and breath sounds; administer oxygen and provide ventilation support as needed.
• Circulation: Check pulse, blood pressure, capillary refill, and skin color; initiate CPR, IV access, and fluid resuscitation when indicated.

Clinical Significance

The ABC framework is the cornerstone of Basic and Advanced Life Support (BLS/ACLS) and is applied in every acute care setting. A compromised airway kills faster than breathing problems, which kill faster than circulatory failure, reinforcing the order.

Nursing Considerations

When facing 'first action' or 'which patient first' questions, the ABC hierarchy almost always selects the correct answer. Newer variations include ABCDE (adding Disability and Exposure) for trauma, and CAB (Compression-Airway-Breathing) for adult cardiac arrest per the American Heart Association.

NCLEX Relevance

ABCs is the gold standard strategy for prioritization questions. When ABCs do not distinguish options, fall back to Maslow's hierarchy or the nursing process.