2.2 Compressions: Rate, Depth, Recoil, and Interruptions
Key Takeaways
- Adult compression rate is 100 to 120 per minute.
- Adult compression depth is at least 2 inches while avoiding excessive depth beyond about 2.4 inches.
- Full chest recoil matters because leaning reduces venous return and cardiac output.
- Minimize pauses, especially around rhythm checks, shocks, airway attempts, and compressor switches.
2.2 Compressions: Rate, Depth, Recoil, and Interruptions
High-quality compressions are the most tested BLS skill. Rate, depth, recoil, hand position, compression fraction, and quick compressor rotation are all common written and skills-check items.
Current official baseline
The adult BLS guidance covers recognition of cardiac arrest, emergency response activation, high-quality CPR, AED use, adult foreign-body airway obstruction, and opioid antagonist integration. Use the official AHA 2025 Adult Basic Life Support Guidelines page when your course materials or training-center instructions differ from third-party summaries: AHA 2025 Adult Basic Life Support Guidelines.
What you need to know
| Decision point | What to do |
|---|---|
| Rate | Use 100 to 120 compressions per minute. Going too slowly underperfuses; going too fast often causes shallow compressions and poor recoil. |
| Depth | For adults, compress at least 2 inches and avoid excessive depth. Use body weight, locked elbows, and a stable position over the sternum. |
| Recoil | Release pressure completely after each compression without lifting hands off the chest. Recoil lets the heart refill. |
| Pauses | Plan rhythm checks, shocks, and compressor switches before stopping. The team should already know the next task when the pause begins. |
How this shows up on BLS/ACLS questions
BLS and ACLS items usually test priority. Read the patient state first: age, pulse status, breathing status, rhythm, stability, and number of rescuers. Then choose the action that protects perfusion, oxygenation, defibrillation timing, or the correct algorithm branch. If an answer sounds advanced but delays CPR, shock delivery, ventilation, or an urgent stability intervention, it is usually a distractor.
Scenario anchor
A compressor is pushing at 140 per minute and leaning on the chest. The leader should correct the rate, coach full recoil, and switch compressors if fatigue is causing shallow compressions.
Common traps
- Counting fast compressions as good CPR even when depth is poor.
- Leaning between compressions.
- Letting rhythm analysis and pulse checks stretch beyond the minimum needed time.
Study action
Write this section as a one-line rule in your own words, then test it with mixed questions from the BLS/ACLS practice bank. Do not review only the matching topic. Mix it with nearby branches so you can tell when the rule applies and when it does not. For example, compare respiratory arrest with a pulse against pulseless arrest, or compare unstable tachycardia against VF/pVT arrest. The exam rewards that discrimination more than memorizing isolated facts.
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