CPR for Adults: When to Combine Compressions & Breaths

Current AHA/ERC guidelines distinguish two pathways for adult CPR based on witnessed status and arrest etiology.

Scenario 1: Witnessed Sudden Collapse (Presumed Cardiac Etiology)

• Action: Immediately begin Hands-Only CPR (continuous chest compressions 100–120/min, 5–6 cm depth).
• Rationale: Blood oxygen content is initially adequate; compressions circulate it. Interruptions for breaths reduce coronary perfusion pressure.
• Add Breaths When: Advanced airway placed (ETT, supraglottic) → switch to 30:2 or continuous compressions with async ventilations (10/min).

Scenario 2: Unwitnessed / Asphyxial Arrest (Drowning, OD, Trauma, Pediatric)

• Action: 30 Compressions : 2 Breaths from the start.
• Rationale: Hypoxia is primary driver; oxygenation critical. Rescue breaths deliver O₂.

Scenario 3: Ineffective Breathing After Initial Rescue Breaths

• If initial 2 breaths given (e.g., bystander) but no chest rise / no pulse → start 30:2 CPR immediately.

Key Points

• Lay rescuers: Hands-Only CPR for witnessed teen/adult collapse. Trained rescuers: 30:2 if confident.
• Healthcare Providers: 30:2 until advanced airway; then continuous compressions + 10 breaths/min.
• Compression Quality: Rate 100–120, depth 5–6 cm, full recoil, minimize pauses (<10s for breaths/pulse check).
• AED: Apply ASAP; follow prompts.