2026 Latest Update | Basic Life Support
Exam Prep, CPR, AED & High-Quality CPR
Guidelines Study Guide
• This 200-question AHA BLS Practice Test covers all core exam domains including
CPR technique, AED use, airway management, team dynamics, and special
resuscitation scenarios for adult, child, and infant patients
. • Study by attempting each question independently before checking the bolded
correct answer and detailed EXPERT RATIONALE beneath it — this active recall
method builds both recognition and deep conceptual understanding.
QUESTION 1
What is the first action a rescuer should take upon finding an unresponsive
adult victim?
A. Begin chest compressions immediately
B. Open the airway using head-tilt chin-lift
C. Call for help and retrieve an AED
D. Check for a pulse for at least 10 seconds
E. Ensure the scene is safe before approaching
Correct Answer: E. Ensure the scene is safe before approaching
EXPERT RATIONALE: Scene safety is the absolute first priority in any emergency
response. A rescuer who is injured cannot help the victim. Before touching the
patient or initiating any intervention, the rescuer must visually scan for hazards
such as traffic, fire, electrical wires, or unstable structures. Only after confirming
safety should the rescuer approach and assess the victim.
QUESTION 2
,According to AHA BLS guidelines, what is the recommended compression rate
for high-quality CPR in adults?
A. 60–80 compressions per minute
B. 80–100 compressions per minute
C. 100–120 compressions per minute
D. 120–140 compressions per minute
E. At least 150 compressions per minute
Correct Answer: C. 100–120 compressions per minute
EXPERT RATIONALE: The AHA mandates a compression rate of 100–120 per
minute for all age groups during CPR. Rates below 100 are insufficient to maintain
perfusion pressure, while rates above 120 compromise compression depth and
cardiac filling time. Maintaining this rate is a key component of high-quality CPR.
QUESTION 3
What is the correct compression depth for an adult during CPR?
A. At least 1 inch
B. At least 1.5 inches
C. At least 2 inches but no more than 2.4 inches
D. At least 3 inches
E. At least 2.5 inches
Correct Answer: C. At least 2 inches but no more than 2.4 inches
EXPERT RATIONALE: AHA guidelines specify that adult chest compressions must be
at least 2 inches deep to adequately compress the heart and generate blood flow.
However, compressions deeper than 2.4 inches increase the risk of rib fractures,
pneumothorax, and liver lacerations. This precise range balances effectiveness and
safety.
,QUESTION 4
What does AED stand for?
A. Automatic External Defibrillator
B. Automated Electrical Device
C. Automated External Defibrillator
D. Automatic Electrical Defibrillator
E. Advanced Emergency Defibrillator
Correct Answer: C. Automated External Defibrillator
EXPERT RATIONALE: AED stands for Automated External Defibrillator. The word
"automated" reflects that the device automatically analyzes the heart's rhythm and
determines whether a shock is needed without requiring the operator to interpret
the rhythm. It is designed for use by laypersons and trained rescuers alike.
QUESTION 5
When performing CPR on an adult, what is the correct hand placement for
chest compressions?
A. On the upper third of the sternum
B. On the lower half of the sternum, on the center of the chest
C. Directly over the xiphoid process
D. Two fingers above the xiphoid process on the left side
E. On the left side of the chest over the heart
Correct Answer: B. On the lower half of the sternum, on the center of the
chest
EXPERT RATIONALE: Correct hand placement ensures that compressions
effectively compress the heart. The heel of one hand should be placed on the lower
, half of the sternum (breastbone), with the other hand on top, fingers interlaced.
Placing hands too high or over the xiphoid process reduces effectiveness and
increases injury risk.
QUESTION 6
What is the recommended ventilation-to-compression ratio for a single
rescuer performing CPR on an adult?
A. 1 breath every 30 compressions
B. 2 breaths every 15 compressions
C. 2 breaths every 30 compressions
D. 1 breath every 15 compressions
E. 3 breaths every 30 compressions
Correct Answer: C. 2 breaths every 30 compressions
EXPERT RATIONALE: For a single rescuer performing CPR on an adult, the AHA
recommends a 30:2 compression-to-ventilation ratio. After 30 compressions, the
rescuer delivers 2 rescue breaths, each lasting about 1 second. This ratio ensures
adequate oxygenation while minimizing interruptions in chest compressions.
QUESTION 7
What is the correct compression-to-ventilation ratio when two trained
rescuers are performing CPR on an infant?
A. 30:2
B. 15:1
C. 15:2
D. 30:1
E. 20:2