High-Quality BLS & AED
High-quality BLS is the foundation of every ACLS resuscitation — no drug or advanced airway compensates for poor compressions. This chapter covers the compression metrics, minimizing interruptions, and integrating the AED that give a patient the best chance of survival.
The five components of high-quality chest compressions
AHA guidelines define high-quality CPR by measurable targets: (1) a rate of 100 to 120 compressions per minute; (2) a depth of at least 2 inches (5 cm) but no more than 2.4 inches (6 cm) in an average adult; (3) full chest recoil between compressions so the heart can refill; (4) minimizing interruptions, keeping pauses under 10 seconds and aiming for a chest compression fraction of at least 60%; and (5) avoiding excessive ventilation. Rescuers should rotate compressor roles about every 2 minutes (or sooner if fatigued) because compression quality degrades with fatigue, often before the rescuer notices.
Compression-to-ventilation ratio and integrating the AED
Without an advanced airway, use a 30:2 compression-to-ventilation ratio for the single-rescuer adult and two-rescuer adult (child/infant two-rescuer is 15:2). As soon as an AED arrives, power it on, apply the pads, and let it analyze — clear the patient during analysis and shock. If a shock is advised, deliver it and immediately resume compressions without a pulse check. If no shock is advised, resume compressions immediately. Every AED cycle should interrupt compressions for as short a time as possible, because coronary perfusion pressure collapses within seconds of stopping and must be rebuilt with each restart.