High-Quality BLS and Airway Management
The five components of high-quality CPR
- Rate 100–120/min.
- Depth at least 5 cm (2 in) and no more than 6 cm (2.4 in) in the adult, roughly one-third of the anterior-posterior chest diameter.
- Full recoil - do not lean on the chest.
- Minimal interruptions - under 10 seconds, with a compression fraction above 60%.
- Avoid excessive ventilation, and switch compressors every 2 minutes.
Without an advanced airway, use 30:2 (15:2 for two-rescuer child/infant). Once a supraglottic airway or endotracheal tube is in place, compress continuously and give 1 breath every 6 seconds (10/min). Confirm an advanced airway with continuous waveform capnography plus clinical assessment. A brisk rise in end-tidal CO₂ during CPR suggests return of spontaneous circulation; a persistently low value suggests poor compression quality.
Airway basics
Open with head tilt–chin lift (jaw thrust if trauma). An oropharyngeal airway is for the patient without a gag reflex, sized from the corner of the mouth to the angle of the mandible. A nasopharyngeal airway suits the patient with a gag or trismus. Two-rescuer bag-mask technique with a good seal beats a single rescuer every time; squeeze over about 1 second, just enough for visible chest rise.
Traps
Questions love the ratio change after an advanced airway is placed, pulse checks longer than 10 seconds, and the claim that a "perfect" ECG replaces compressions. Also watch for the notation that too-fast, too-shallow compressions with leaning are acceptable - they are not.
Rule of thumb
Push hard, push fast, let it come all the way back, and never stop for more than 10 seconds.