ACLS — Advanced Cardiovascular Life Support — All Questions
15 questions
What is the recommended chest compression rate for high-quality CPR in an adult?
- a.60 to 80 compressions per minute
- b.80 to 100 compressions per minute
- c.100 to 120 compressions per minute✓
- d.120 to 140 compressions per minute
Current AHA guidelines call for a compression rate of 100 to 120 per minute. Rates slower than 100 reduce coronary and cerebral perfusion, while rates faster than 120 shorten the recoil/filling phase and reduce the depth actually achieved, so the diastolic filling of the heart suffers. Staying inside the 100-120 window balances forward blood flow with adequate ventricular filling.
What is the correct chest compression depth for an average adult?
- a.At least 2.5 cm (1 in)
- b.At least 5 cm, not over 6 cm✓
- c.At least 4 cm (1.5 in)
- d.At least 7.5 cm (3 in)
Evidence behind the 2025 AHA Guidelines links survival with compression depths of at least 5 cm (about 2 inches) and reduced survival with excessive depth over 6 cm (about 2.4 inches). Shallower compressions move too little blood; deeper ones risk injury without benefit.
To maximize the chest compression fraction, interruptions in compressions should be limited to less than:
- a.5 seconds
- b.10 seconds✓
- c.20 seconds
- d.30 seconds
Pauses in compressions (for rhythm checks, ventilation, or defibrillation) should be kept under 10 seconds. The goal is a chest compression fraction of at least 60%. Every second without compressions drops coronary perfusion pressure, which then takes several compressions to rebuild, so minimizing hands-off time directly improves the odds of ROSC.
During an ACLS code, the feedback device shows a compression rate of 132 per minute. What should the team leader say?
- a.Slow down to 100–120✓
- b.Switch to breaths only
- c.Pause and restart at 140
- d.Keep going; faster is better
Adult compressions are delivered at 100 to 120 per minute; survival evidence favored rates in that range over faster ones, and faster compressions shorten refilling time.
A code has run 18 minutes with frequent long pauses for pulse checks. What metric is likely too low?
- a.Epinephrine dose
- b.Oxygen flow
- c.Compression fraction✓
- d.Pad size
The chest compression fraction is the share of time with compressions; pulse checks longer than 10 seconds reduce it, and 60% is the minimum target.
Why does the ACLS team leader watch compression quality even while ordering drugs?
- a.Drugs work only after compressions stop
- b.CPR is the most critical intervention✓
- c.Compressions matter only before the first shock
- d.The leader must do compressions personally
The Guidelines call high-quality CPR the single most critical intervention for a patient in cardiac arrest; drugs and airways support resuscitation but perfusion comes from compressions.
During CPR the ETCO2 is 9 mm Hg. What adjustment is most likely to help?
- a.Give sodium bicarbonate
- b.Increase ventilations to 30 per minute
- c.Stop CPR for a rhythm check
- d.Improve compression depth and rate✓
ETCO2 reflects cardiac output during CPR and rises with better compression depth; the Guidelines suggest targeting at least 10 and ideally 20 mm Hg. Faster ventilation risks harm and bicarbonate is not routine.
How often should compressors switch during a prolonged resuscitation?
- a.Every 30 seconds
- b.Only when exhausted
- c.About every 2 minutes✓
- d.Every 10 minutes
Depth falls after 90 to 120 seconds, so rotating the compressor about every 2 minutes, at the planned rhythm check, keeps quality up.
After a shock, a resident wants to check for a pulse before resuming CPR. What is the correct practice?
- a.Wait for the monitor to settle
- b.Give a second shock first
- c.Resume CPR immediately✓
- d.Check the pulse for 10 seconds
Immediate resumption of compressions after a shock shortens the perishock pause and improves hands-on time; rhythm and pulse are checked after 2 minutes.
A patient in arrest is on a soft ICU bed. What quickly improves compression depth?
- a.Mechanical CPR as routine
- b.Faster compressions on the soft bed
- c.Moving to a stretcher in the hallway
- d.The bed's CPR mode or a backboard✓
A firm surface improves depth; the Guidelines note that a backboard, a deflated dynamic mattress or the bed's CPR mode can improve compression depth in hospital.
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What is the minimum chest compression fraction target during adult CPR?
- a.30%
- b.45%
- c.60%✓
- d.100%
A compression fraction of 60% is considered a minimum target, and high-performing teams may exceed 80%.
An intubated adult receives CPR. How are compressions and ventilations coordinated?
- a.15:2 cycles with pauses
- b.Continuous CPR; 10 breaths/min✓
- c.30:2 cycles with pauses
- d.Compressions pause for every breath
With an advanced airway, compressions continue without pausing for ventilations, which are given at about 10 per minute.
Why is excessive ventilation during ACLS harmful?
- a.It prevents ROSC entirely
- b.It causes VF
- c.It lowers ETCO2 to zero
- d.It reduces cardiac output✓
Excessive ventilation can cause gastric inflation, regurgitation, aspiration and decreased cardiac output; too little is also harmful.
Which statement reflects the 2025 position on mechanical CPR devices in hospitals?
- a.Not recommended for routine use✓
- b.Recommended for every in-hospital arrest
- c.Required once an airway is placed
- d.Proven to improve survival
Mechanical CPR has not been shown better than manual CPR for survival, so routine use is not recommended; it may be considered where manual CPR cannot be maintained.
A nurse asks whether a step stool is useful during CPR on a high bed. What does the 2025 guidance say?
- a.Only when using mechanical CPR
- b.Yes; knees level with the torso✓
- c.Only for pediatric patients
- d.No; rescuers should always stand
Rescuers should position themselves so that their knee is aligned with the patient's torso, by kneeling or using a step stool, to improve compression quality.