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AHA BLS Provider practice questions

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Question 1Chain of Survival and High-Quality CPR

In the out-of-hospital Chain of Survival for adults, which action comes immediately after recognizing cardiac arrest and activating the emergency response system?

  1. Post-arrest care
  2. Advanced life support
  3. Defibrillation with an AED
  4. Beginning high-quality CPR Correct answer.

Explanation

The out-of-hospital chain begins with recognition and activation, then moves to immediate high-quality CPR before defibrillation. CPR provides circulation while the AED is retrieved and applied. Advanced care and post-arrest care come later in the chain.

Question 2Chain of Survival and High-Quality CPR

Which link appears in the in-hospital adult Chain of Survival but not in the out-of-hospital chain?

  1. Defibrillation
  2. Rapid response team activation Correct answer.
  3. Immediate high-quality CPR
  4. Recognition of arrest

Explanation

The in-hospital chain includes surveillance and prevention plus rapid response team activation, reflecting the monitored hospital environment. CPR, defibrillation, and recognition appear in both chains.

Question 3Chain of Survival and High-Quality CPR

What is the recommended compression rate for high-quality CPR in an adult?

  1. 80 to 100 per minute
  2. 140 to 160 per minute
  3. 100 to 120 per minute Correct answer.
  4. 60 to 80 per minute

Explanation

High-quality CPR calls for a compression rate of 100 to 120 per minute. Rates that are too slow reduce cardiac output, and rates above 120 reduce compression depth and chest recoil.

Question 4Chain of Survival and High-Quality CPR

What compression depth should a rescuer achieve when performing CPR on an average adult?

  1. About 3 cm
  2. About 4 cm
  3. About 2 cm
  4. At least 5 cm but no more than 6 cm Correct answer.

Explanation

Adult compressions should depress the chest at least 5 cm while avoiding depths greater than 6 cm. Excessive depth raises the risk of injury without improving hemodynamics.

Question 5Chain of Survival and High-Quality CPR

A rescuer finishes each chest compression and allows the chest to come fully back to its resting position. Why is this important?

  1. It reduces the risk of rib fracture
  2. It slows the compression rate
  3. It increases the force of the next compression
  4. It allows the heart to refill before the next compression Correct answer.

Explanation

Full chest recoil permits venous return and refilling of the heart between compressions. Leaning on the chest raises intrathoracic pressure and reduces the blood pumped with each compression.

Question 6Chain of Survival and High-Quality CPR

Two rescuers are performing CPR on an adult. When should they exchange the compressor role?

  1. About every 2 minutes Correct answer.
  2. Only when the compressor asks
  3. Every 10 minutes
  4. Every 5 minutes

Explanation

Compressors should switch roughly every 2 minutes, or sooner if fatigued, to preserve compression quality. The switch should be coordinated to minimize interruption.

Question 7Chain of Survival and High-Quality CPR

What is the maximum acceptable interruption in chest compressions when a rescuer pauses to deliver a shock?

  1. About 20 seconds
  2. About 30 seconds
  3. Less than 10 seconds Correct answer.
  4. About 45 seconds

Explanation

Any pause in compressions, including for rhythm analysis or shock delivery, should be kept under 10 seconds. Shorter pauses preserve coronary perfusion pressure.

Question 8Chain of Survival and High-Quality CPR

Which statement best describes adequate chest recoil during adult CPR?

  1. The rescuer compresses and releases in a rapid continuous motion without pause
  2. The rescuer allows the chest to expand fully while keeping hands in contact Correct answer.
  3. The rescuer keeps slight pressure on the sternum between compressions
  4. The rescuer lifts the hands completely off the chest between compressions

Explanation

Rescuers should keep their hands in contact with the chest but release all downward force so the chest expands fully. Leaning prevents complete recoil and impairs filling.

Question 9Chain of Survival and High-Quality CPR

A single rescuer is alone with an adult who has suddenly collapsed and is unresponsive with no normal breathing. What should the rescuer do first?

  1. Start chest compressions after calling for help Correct answer.
  2. Check for a pulse for 30 seconds
  3. Give two rescue breaths
  4. Apply an AED before compressions

Explanation

For an adult with no normal breathing, the rescuer should activate the emergency response system and begin CPR, starting with compressions. Compressions are the priority because circulation is absent.

Question 10Chain of Survival and High-Quality CPR

During CPR on an adult, what is the recommended compression-to-ventilation ratio for a single rescuer?

  1. 50:2
  2. 30:2 Correct answer.
  3. 10:2
  4. 15:2

Explanation

Adults receive compressions and ventilations in a 30:2 ratio regardless of the number of rescuers. This ratio applies until an advanced airway is placed.

Question 11Chain of Survival and High-Quality CPR

When should a rescuer begin CPR on an adult who is unresponsive?

  1. After checking for a pulse for no more than 10 seconds and finding none Correct answer.
  2. After giving two rescue breaths
  3. After confirming the absence of a pulse for at least 30 seconds
  4. After the AED advises no shock

Explanation

Rescuers should check for a pulse for no more than 10 seconds; if none is felt, compressions should begin. Prolonged pulse checks delay life-saving compressions.

Question 12Chain of Survival and High-Quality CPR

Which finding indicates that a rescuer's chest compressions are of high quality?

  1. A femoral pulse is felt with each compression Correct answer.
  2. The rescuer is sweating and breathing hard
  3. The rescuer's arms are bent at the elbows
  4. The chest is visibly rising with each compression

Explanation

Feeling a pulse with compressions suggests adequate depth and force. Visible chest rise reflects ventilation, not compression quality, and bent elbows reduce force transmission.

Question 13Chain of Survival and High-Quality CPR

A rescuer is performing compressions with straight arms and the heels of both hands on the lower half of the sternum. What is the main purpose of this technique?

  1. To transmit body weight into the chest efficiently Correct answer.
  2. To reduce the risk of gastric inflation
  3. To slow the compression rate
  4. To allow the rescuer to ventilate more easily

Explanation

Positioning the shoulders over the hands with straight arms allows the rescuer to use body weight rather than arm strength, improving depth and reducing fatigue.

Question 14Chain of Survival and High-Quality CPR

How should a rescuer deliver rescue breaths during two-rescuer adult CPR before an advanced airway is placed?

  1. Two breaths after every 30 compressions, each over about 1 second Correct answer.
  2. Two breaths after every 15 compressions
  3. One breath every 2 seconds
  4. Continuous breaths during compressions

Explanation

Before an advanced airway is in place, rescuers deliver two breaths after each set of 30 compressions, each breath over about 1 second with visible chest rise.

Question 15Chain of Survival and High-Quality CPR

After an advanced airway is placed during adult CPR, how should ventilations be delivered?

  1. Two breaths after every 30 compressions
  2. One breath every 6 seconds without pausing compressions Correct answer.
  3. One breath every 10 seconds with a pause in compressions
  4. Two breaths after every 15 compressions

Explanation

With an advanced airway, ventilations are given asynchronously at about one breath every 6 seconds while compressions continue without interruption.

Question 16Chain of Survival and High-Quality CPR

A rescuer delivers a breath that produces no visible chest rise. What is the most appropriate next step?

  1. Give a much larger breath
  2. Reposition the head and try again Correct answer.
  3. Stop ventilations and continue compressions only
  4. Increase the rate of compressions

Explanation

If a breath does not produce chest rise, the airway is likely obstructed or the head position is inadequate. Repositioning the head and reattempting improves the chance of effective ventilation.

Question 17Chain of Survival and High-Quality CPR

What is the primary purpose of defibrillation in the Chain of Survival?

  1. To restart the heart's normal rhythm in a shockable arrest Correct answer.
  2. To improve the depth of chest compressions
  3. To open the airway
  4. To increase the oxygen content of the blood

Explanation

Defibrillation delivers an electrical shock to terminate a shockable rhythm such as ventricular fibrillation and allow a normal rhythm to resume. CPR maintains circulation until a defibrillator is available.

Question 18Chain of Survival and High-Quality CPR

An AED is applied to an adult in cardiac arrest and advises a shock. What should the rescuer do immediately after delivering the shock?

  1. Resume chest compressions right away Correct answer.
  2. Wait for the AED to reanalyze
  3. Check for a pulse for 10 seconds
  4. Give two rescue breaths

Explanation

Compressions should resume immediately after a shock to minimize interruption and maintain perfusion. The AED will prompt for rhythm reanalysis after the next cycle.

Question 19Chain of Survival and High-Quality CPR

Which action best helps minimize interruptions in chest compressions during a resuscitation?

  1. Pausing compressions to discuss the rhythm
  2. Switching compressors every 30 seconds
  3. Checking a pulse after every cycle
  4. Charging the defibrillator while compressions continue Correct answer.

Explanation

Charging the defibrillator during ongoing compressions shortens the pause needed for shock delivery. Frequent or unnecessary pauses reduce coronary perfusion and survival.

Question 20Chain of Survival and High-Quality CPR

Which statement accurately describes the role of post-cardiac arrest care in the Chain of Survival?

  1. It is performed only in the out-of-hospital setting
  2. It is the final link, focused on stabilizing and supporting recovery after return of spontaneous circulation Correct answer.
  3. It begins before defibrillation
  4. It replaces the need for high-quality CPR

Explanation

Post-cardiac arrest care follows return of spontaneous circulation and focuses on stabilizing the patient and supporting recovery. It occurs in both in-hospital and out-of-hospital chains.

Question 21Chain of Survival and High-Quality CPR

Why does the Chain of Survival emphasize early recognition and activation of the emergency response system?

  1. It shortens the time to CPR and defibrillation Correct answer.
  2. It replaces the need for an AED
  3. It ensures a pulse is present
  4. It allows the rescuer to avoid compressions

Explanation

Early recognition and activation reduce the delay before CPR and defibrillation begin, which improves survival. Each minute of delay lowers the chance of a good outcome.

Question 22Chain of Survival and High-Quality CPR

A team is performing CPR on an adult when the AED announces it is analyzing the rhythm. What should the team do?

  1. Continue compressions and ventilations as usual
  2. Stop compressions and ensure no one is touching the patient Correct answer.
  3. Switch compressors during analysis
  4. Continue compressions at a slower rate

Explanation

Compressions must stop and no one should touch the patient during rhythm analysis so the AED can read the rhythm accurately. Compressions resume as soon as analysis is complete.

Question 23Chain of Survival and High-Quality CPR

Which factor most directly reduces the effectiveness of chest compressions during a prolonged resuscitation?

  1. Presence of a second rescuer
  2. Use of an AED
  3. Use of a bag-mask device
  4. Rescuer fatigue leading to shallower compressions Correct answer.

Explanation

Fatigue causes rescuers to compress too shallowly and too slowly, reducing cardiac output. Rotating compressors about every 2 minutes helps maintain quality.

Question 24Chain of Survival and High-Quality CPR

What is the recommended hand position for chest compressions on an adult?

  1. On the upper third of the sternum
  2. On the xiphoid process
  3. Over the left nipple
  4. On the lower half of the sternum, heels of both hands Correct answer.

Explanation

The heels of both hands are placed on the lower half of the sternum, with the rescuer's shoulders over the hands. This position compresses the heart effectively.

Question 25Chain of Survival and High-Quality CPR

A rescuer notes that the chest is not fully recoiling between compressions. Which change is most appropriate?

  1. Pause compressions to ventilate more often
  2. Release all downward pressure while keeping hands in contact Correct answer.
  3. Increase the compression rate
  4. Reduce the depth of compressions

Explanation

Leaning on the chest prevents full recoil; releasing all downward force while keeping hands in contact restores it. Full recoil supports venous return and cardiac filling.

Question 26Chain of Survival and High-Quality CPR

In the out-of-hospital Chain of Survival for adults, which link comes immediately after high-quality CPR?

  1. Advanced resuscitation interventions
  2. Recovery and rehabilitation
  3. Post-cardiac arrest care
  4. Defibrillation with an AED Correct answer.

Explanation

The out-of-hospital sequence runs from recognition and activation through CPR, defibrillation, advanced resuscitation, post-cardiac arrest care, and recovery. Defibrillation follows CPR directly because early shock is most effective when delivered promptly.

Question 27Chain of Survival and High-Quality CPR

What is the recommended adult chest compression rate during CPR?

  1. 100 to 120 per minute Correct answer.
  2. 80 to 100 per minute
  3. 60 to 80 per minute
  4. 140 to 160 per minute

Explanation

High-quality CPR for adults uses a compression rate of 100 to 120 per minute. Rates below this reduce cardiac output, and rates above it shorten filling time and decrease compression depth.

Question 28Chain of Survival and High-Quality CPR

What is the recommended compression depth for an adult during CPR?

  1. At least 3 inches (7.5 cm)
  2. At least 2 inches (5 cm) but no more than 2.4 inches (6 cm) Correct answer.
  3. About 1 inch (2.5 cm)
  4. Depth is not specified for adults

Explanation

Adult compressions should depress the chest at least 2 inches (5 cm) while avoiding depths greater than about 2.4 inches (6 cm). Compressions that are too shallow produce little flow, and excessive depth raises injury risk.

Question 29Chain of Survival and High-Quality CPR

Which action is part of the recognition and activation link of the adult Chain of Survival?

  1. Calling for emergency help when a person is unresponsive and not breathing normally Correct answer.
  2. Providing targeted temperature management after resuscitation
  3. Attaching an AED and delivering a shock
  4. Performing two-rescuer CPR

Explanation

Recognition and activation means identifying that a person is in cardiac arrest and promptly summoning the emergency response system. This early step starts the chain and shortens the time to CPR and defibrillation.

Question 30Chain of Survival and High-Quality CPR

A lone rescuer finds an adult collapsed in a gym. After confirming unresponsiveness and absent normal breathing, what should the rescuer do first?

  1. Activate the emergency response system and get an AED Correct answer.
  2. Check for a pulse for at least 30 seconds
  3. Begin compressions and delay any call for help
  4. Give two rescue breaths

Explanation

For an adult in cardiac arrest, the rescuer should activate the emergency response system and obtain an AED, then start CPR. Prompt activation brings advanced help and defibrillation sooner.

Question 31Chain of Survival and High-Quality CPR

Which statement about chest recoil during adult CPR is accurate?

  1. Full recoil allows the heart to refill before the next compression Correct answer.
  2. Recoil matters only when an advanced airway is in place
  3. Recoil should be avoided during two-rescuer CPR
  4. Leaning on the chest between compressions improves flow

Explanation

Complete chest recoil lets the chest expand and the heart refill with blood between compressions. Leaning on the chest impairs filling and reduces the effectiveness of subsequent compressions.

Question 32Chain of Survival and High-Quality CPR

What is the compression-to-ventilation ratio for two-rescuer adult CPR before an advanced airway is placed?

  1. 15:2
  2. 30:2 Correct answer.
  3. 5:1
  4. Continuous compressions with no breaths

Explanation

Before an advanced airway is placed, adult CPR uses 30 compressions to 2 ventilations whether one or two rescuers are present. This ratio balances circulation and ventilation.

Question 33Chain of Survival and High-Quality CPR

In the in-hospital adult Chain of Survival, which element is emphasized that is not a separate link in the out-of-hospital chain?

  1. Bystander CPR
  2. Emergency response activation
  3. Surveillance and prevention of deterioration Correct answer.
  4. Rapid defibrillation

Explanation

The in-hospital chain includes surveillance and prevention, recognizing that many in-hospital arrests are preceded by warning signs. Early detection and response can prevent deterioration to cardiac arrest.

Question 34Chain of Survival and High-Quality CPR

A rescuer is compressing an adult's chest at 130 per minute. What is the most likely consequence of this rate?

  1. Reduced depth and incomplete recoil Correct answer.
  2. Better coronary perfusion than 110 per minute
  3. No effect on CPR quality
  4. Improved compression depth

Explanation

Rates above 120 per minute tend to reduce compression depth and prevent full chest recoil. Both effects lower cardiac output and coronary perfusion.

Question 35Chain of Survival and High-Quality CPR

During a resuscitation, a compressor's hands slide slightly off the lower half of the sternum toward the ribs. What is the most appropriate correction?

  1. Reposition the hands on the lower half of the sternum and resume compressions Correct answer.
  2. Increase compression rate to compensate
  3. Move the hands to the upper sternum
  4. Continue compressions at the new position

Explanation

Compressions belong on the lower half of the sternum to compress the heart effectively and reduce injury risk. The rescuer should reposition promptly and resume with minimal interruption.

Question 36Chain of Survival and High-Quality CPR

A team pauses compressions for 20 seconds while a new rescuer takes over. How does this pause affect the patient?

  1. It reduces coronary perfusion pressure and lowers the chance of survival Correct answer.
  2. It improves circulation by allowing the heart to rest
  3. It has little effect because compressions resume quickly
  4. It is acceptable if the pause is under 30 seconds

Explanation

Interruptions in compressions cause coronary perfusion pressure to fall, and pressure must be rebuilt after compressions resume. Keeping interruptions under 10 seconds preserves perfusion and improves outcomes.

Question 37Chain of Survival and High-Quality CPR

Which action best supports high-quality CPR during a prolonged resuscitation?

  1. Hyperventilating the patient between cycles
  2. Allowing the compressor to continue until exhausted
  3. Rotating the compressor role about every 2 minutes Correct answer.
  4. Pausing compressions to discuss the rhythm

Explanation

Compressors fatigue within a few minutes, and fatigue reduces depth and recoil. Rotating about every 2 minutes, with a brief coordinated switch, maintains compression quality.

Question 38Chain of Survival and High-Quality CPR

A rescuer delivers ventilations that are larger and faster than needed during adult CPR. What is the likely effect?

  1. Increased venous return and better compressions
  2. Improved oxygenation with no downside
  3. Increased intrathoracic pressure and reduced cardiac output Correct answer.
  4. Faster return of spontaneous circulation

Explanation

Excessive ventilation raises pressure inside the chest, which impedes blood return to the heart and lowers cardiac output. Each breath should be given over about 1 second with just enough volume to make the chest rise.

Question 39Chain of Survival and High-Quality CPR

Which of the following best describes the purpose of the CPR link in the adult Chain of Survival?

  1. To provide post-arrest neurologic care
  2. To circulate oxygenated blood to the brain and heart until defibrillation or advanced care is available Correct answer.
  3. To restore an organized rhythm with an electric shock
  4. To diagnose the underlying cause of the arrest

Explanation

CPR maintains some blood flow to the brain and heart when the heart is not pumping effectively. This buys time until defibrillation or advanced interventions can restore circulation.

Question 40Chain of Survival and High-Quality CPR

A rescuer is unsure whether an unresponsive adult has a pulse and takes 25 seconds to decide. Why is this problematic?

  1. Pulse checks are unnecessary in all cases
  2. Pulse checks should last at least 30 seconds for accuracy
  3. Pulse checks longer than 10 seconds delay needed compressions Correct answer.
  4. A pulse must be checked before calling for help

Explanation

Pulse checks should take no more than 10 seconds; if a pulse is not definitely felt, compressions should begin. Prolonged checks delay CPR and reduce survival.

Question 41Chain of Survival and High-Quality CPR

When should a rescuer stop CPR to check the patient's rhythm or pulse?

  1. Only when the AED prompts analysis or a sign of life appears, keeping pauses brief Correct answer.
  2. Whenever a team member suggests it
  3. After every set of 5 cycles regardless of signs
  4. Every 30 seconds

Explanation

Compressions should continue with minimal interruption, and rhythm or pulse checks are performed only when the AED analyzes or when the patient shows signs of life. Any pause should be kept under about 10 seconds.

Question 42Chain of Survival and High-Quality CPR

During two-rescuer adult CPR, the compressor counts aloud and pauses briefly at 30 compressions. What is the best explanation for this practice?

  1. It permits the AED to analyze continuously
  2. It reduces the risk of rib fracture
  3. It allows the ventilator to give two breaths with coordinated timing and minimal interruption Correct answer.
  4. It gives the patient a rest period

Explanation

Counting compressions coordinates the switch to ventilations so the two breaths are delivered promptly. The goal is to keep the pause for ventilation as short as possible.

Question 43Chain of Survival and High-Quality CPR

A rescuer's compressions produce only about 1 inch of chest displacement. What is the most appropriate action?

  1. Continue because some compression is better than none
  2. Switch to ventilations only
  3. Increase the rate to make up for shallow depth
  4. Increase depth to at least 2 inches (5 cm) while allowing full recoil Correct answer.

Explanation

Compressions must reach at least 2 inches (5 cm) in adults to generate adequate blood flow. The rescuer should correct depth and ensure full recoil between compressions.

Question 44Chain of Survival and High-Quality CPR

Which sequence correctly orders the first four links of the out-of-hospital adult Chain of Survival?

  1. Defibrillation, recognition and activation, CPR, advanced resuscitation
  2. CPR, defibrillation, recognition and activation, advanced resuscitation
  3. Recognition and activation, defibrillation, CPR, advanced resuscitation
  4. Recognition and activation, CPR, defibrillation, advanced resuscitation Correct answer.

Explanation

The out-of-hospital chain begins with recognition and activation, followed by CPR, defibrillation, and advanced resuscitation. Each link builds on the previous one to shorten time to definitive care.

Question 45Chain of Survival and High-Quality CPR

Why is early defibrillation placed so high in the adult Chain of Survival?

  1. It eliminates the need for advanced care
  2. Survival falls with each minute that defibrillation is delayed for a shockable rhythm Correct answer.
  3. It replaces the need for chest compressions
  4. It works equally well for non-shockable rhythms

Explanation

For shockable rhythms such as ventricular fibrillation, the probability of survival decreases substantially with each minute of delay to defibrillation. Early shock can restore an organized rhythm before irreversible damage occurs.

Question 46Chain of Survival and High-Quality CPR

A two-rescuer team is about to switch compressor roles. Which approach best preserves CPR quality?

  1. Wait until the compressor is completely exhausted
  2. Pause compressions for 15 seconds to reposition equipment
  3. Perform the switch during the planned rhythm analysis with a coordinated, brief exchange Correct answer.
  4. Stop compressions, discuss the patient's history, then switch

Explanation

Compressor switches should be planned and coordinated to occur with minimal interruption, ideally during a rhythm analysis. Keeping pauses under 10 seconds preserves coronary perfusion pressure.

Question 47Chain of Survival and High-Quality CPR

A team notices that compressions become shallower over several minutes despite the same compressor. What is the best interpretation and response?

  1. Compressor fatigue is reducing depth; rotate the compressor promptly Correct answer.
  2. The AED is interfering with compressions; stop CPR
  3. The patient's chest has become more compliant; continue unchanged
  4. Deeper compressions are no longer needed; reduce effort

Explanation

Progressive loss of compression depth is a classic sign of rescuer fatigue. Rotating the compressor, typically about every 2 minutes, restores depth and recoil quality.

Question 48Chain of Survival and High-Quality CPR

During CPR, a rescuer hyperventilates the patient at about 20 breaths per minute through a bag-mask. Which physiologic effect is most likely?

  1. Increased intrathoracic pressure and decreased venous return to the heart Correct answer.
  2. No measurable hemodynamic effect
  3. Increased coronary perfusion pressure
  4. Decreased intrathoracic pressure and improved venous return

Explanation

Excessive rate or volume raises mean intrathoracic pressure, which impedes venous return and lowers cardiac output and coronary perfusion. Ventilations should be delivered at the recommended rate with only enough volume for visible chest rise.

Question 49Chain of Survival and High-Quality CPR

A rescuer pauses compressions to search for a pulse after each cycle of 30 compressions and 2 breaths. How does this practice affect the resuscitation?

  1. It creates unnecessary interruptions that reduce coronary perfusion pressure Correct answer.
  2. It is required before every ventilation
  3. It shortens the total resuscitation time
  4. It improves outcomes by confirming circulation frequently

Explanation

Routine pulse checks after each cycle are not recommended because they add interruptions that lower coronary perfusion pressure. Compressions should continue until the AED analyzes or the patient shows signs of life.

Question 50Chain of Survival and High-Quality CPR

Which combination best reflects high-quality adult CPR?

  1. Rate 120 to 140 per minute, depth 3 inches, leaning between compressions
  2. Rate 60 per minute, depth 2 inches, long pauses for ventilation
  3. Rate 80 to 100 per minute, depth 1 inch, full recoil
  4. Rate 100 to 120 per minute, depth at least 2 inches (5 cm), full recoil, minimal interruptions Correct answer.

Explanation

High-quality CPR combines a rate of 100 to 120 per minute, a depth of at least 2 inches (5 cm) but no more than 2.4 inches (6 cm), complete recoil, and interruptions kept under 10 seconds. These elements together maximize perfusion.