Sudden Cardiac Arrest, the Chain of Survival, and Bystander and Dispatcher CPR Practice Questions

25 multiple-choice questions on Sudden cardiac arrest, the chain of survival, and bystander and dispatcher CPR for paramedic and EMT students, from Chapter 40 (Responding to the Field Code). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. The 2025 AHA guidelines changed the chain of survival by:

   1. A. Dropping the recovery link from the chain
   2. B. Using one chain for all cardiac arrests
   3. C. Moving defibrillation ahead of CPR
   4. D. Adding a separate chain for drowning
   Show answer

   Answer: B. Using one chain for all cardiac arrests

   In 2025 the AHA went back to a single chain of survival for every cardiac arrest, adult or child, in or out of the hospital, instead of the four chains used in 2020. The chain still runs from recognition and activation through CPR, defibrillation, advanced care, and post-arrest care to recovery. Recovery was kept, not dropped; survivors still need long-term physical, cognitive, and emotional support. Defibrillation did not move ahead of CPR; compressions start while the defibrillator is readied. No separate drowning chain was created; the single chain stresses breaths for asphyxial arrests such as drowning and pediatric arrest. (2025 AHA Guidelines, Part 1 Executive Summary and Part 4 Systems of Care.)

2. The first link in the adult out-of-hospital chain of survival is:

   1. A. Recognition and 9-1-1 activation
   2. B. Immediate high-quality CPR
   3. C. Rapid defibrillation
   4. D. Advanced resuscitation
   Show answer

   Answer: A. Recognition and 9-1-1 activation

   Nothing else in the chain can start until someone recognizes the arrest and activates EMS. High-quality CPR is the second link; it follows recognition, often with dispatcher coaching.

3. Most adult out-of-hospital cardiac arrests occur:

   1. A. On a street or highway
   2. B. In a public building
   3. C. In a private residence
   4. D. At a workplace or job site
   Show answer

   Answer: C. In a private residence

   About 70% of out-of-hospital arrests happen at home, which is why family CPR training and dispatcher-assisted CPR matter so much. Public locations account for a smaller share, although they more often have witnesses and AEDs.

4. The most common underlying cause of sudden cardiac death in adults is:

   1. A. Hypertrophic cardiomyopathy
   2. B. Pulmonary embolism
   3. C. Commotio cordis
   4. D. Coronary artery disease
   Show answer

   Answer: D. Coronary artery disease

   Ischemic heart disease causes most adult sudden cardiac deaths, typically through a lethal ventricular dysrhythmia. Hypertrophic cardiomyopathy is an important cause in young athletes but is uncommon in the overall adult population.

5. Which initial cardiac arrest rhythm is associated with the best chance of survival to hospital discharge?

   1. A. Asystole
   2. B. Pulseless electrical activity
   3. C. Ventricular fibrillation
   4. D. Agonal idioventricular rhythm
   Show answer

   Answer: C. Ventricular fibrillation

   VF is the most treatable arrest rhythm because it responds to early defibrillation, and survival is several times higher than with nonshockable rhythms. PEA has better odds than asystole but still far lower survival than VF.

6. For each minute that a VF arrest goes without CPR or defibrillation, the chance of survival falls by about:

   1. A. 7% to 10%
   2. B. 1% to 2%
   3. C. 25% to 30%
   4. D. 40% to 50%
   Show answer

   Answer: A. 7% to 10%

   Survival from untreated VF drops roughly 7% to 10% per minute; bystander CPR slows this decline to about 3% to 4% per minute. A loss of only 1% to 2% per minute would understate how time-critical early CPR and defibrillation are.

7. A caller says her 62-year-old husband collapsed and is 'breathing weird,' with a snoring gasp every 10 seconds. He does not respond to shouting. The dispatcher should:

   1. A. Have her place him in the recovery position
   2. B. Ask her to check for a carotid pulse first
   3. C. Coach her to give two rescue breaths first
   4. D. Coach compressions as for cardiac arrest
   Show answer

   Answer: D. Coach compressions as for cardiac arrest

   Occasional gasps in an unresponsive person are agonal breaths, a sign of cardiac arrest, so the dispatcher should start compression coaching at once. Mistaking gasps for breathing and placing the patient in the recovery position is a leading cause of delayed CPR.

8. For an adult cardiac arrest, a dispatcher coaching an untrained lay caller should instruct:

   1. A. Compressions and mouth-to-mouth at 30:2
   2. B. Compression-only CPR
   3. C. Rescue breathing at 1 breath every 6 s
   4. D. Abdominal thrusts, then compressions
   Show answer

   Answer: B. Compression-only CPR

   Hands-only CPR is easier to coach by phone and works as well as conventional CPR for most adult cardiac arrests in the first minutes. Mouth-to-mouth adds hesitation and interruptions for untrained callers; breaths matter more in asphyxial arrests such as drowning and in children.

9. Under AHA telecommunicator CPR performance measures, the benchmark from call receipt to the first dispatcher-directed compression is under:

   1. A. 150 seconds
   2. B. 45 seconds
   3. C. 300 seconds
   4. D. 600 seconds
   Show answer

   Answer: A. 150 seconds

   The AHA benchmarks are recognition of cardiac arrest within 90 seconds of the call being received and the first telecommunicator-directed compression within 150 seconds, with arrest recognized in at least 75% of cases. The two clocks are easy to mix up: 90 seconds is the recognition target, not the compression target. Forty-five seconds is not a published benchmark and is rarely achievable once the address, the patient's position, and hand placement have been confirmed. Five minutes (300 s) and 10 minutes (600 s) would waste the minutes in which bystander CPR does the most good, since survival from untreated VF falls about 7% to 10% per minute. (AHA Telecommunicator CPR Recommendations and Performance Measures.)

10. A caller trained in CPR reports that her 8-month-old was found limp and not breathing in his crib. The dispatcher should coach her to give:

    1. A. Compression-only CPR until EMS arrives
    2. B. Back blows and chest thrusts first
    3. C. Compressions and breaths at 30:2
    4. D. Rescue breaths only, no compressions
    Show answer

    Answer: C. Compressions and breaths at 30:2

    Most infant arrests are asphyxial, so a caller who is able should give compressions with rescue breaths; a single rescuer uses 30:2 for infants and children. Compression-only CPR is far better than nothing and is what dispatchers coach when the caller cannot or will not give breaths, but it is not the first choice in an infant. Back blows and chest thrusts are for a conscious choking infant, and nothing here suggests an obstruction. Breaths alone are for an infant who has a pulse; a limp infant who is not breathing gets CPR. (2025 AHA/AAP pediatric BLS; AHA T-CPR recommendations.)

11. Public-access defibrillation programs improve survival from cardiac arrest mainly because they:

    1. A. Remove the need for any bystander CPR
    2. B. Let lay rescuers interpret rhythms
    3. C. Reduce EMS response times
    4. D. Shorten the time to the first shock
    Show answer

    Answer: D. Shorten the time to the first shock

    Placing AEDs where arrests happen lets bystanders shock VF minutes before EMS arrives, and survival depends heavily on time to defibrillation. AEDs work alongside CPR rather than replacing it, and the device, not the rescuer, analyzes the rhythm.

12. The recovery link of the chain of survival addresses:

    1. A. Return of spontaneous circulation on scene
    2. B. Physical, cognitive, and emotional rehab
    3. C. Crew rest and restocking after the call
    4. D. Recovery position for the unresponsive breather
    Show answer

    Answer: B. Physical, cognitive, and emotional rehab

    Recovery covers the months after discharge, when survivors and families often face cognitive deficits, anxiety, depression, and fatigue and need structured rehabilitation. ROSC is the goal of advanced resuscitation, an earlier link, not the recovery link.

13. A high school is writing an emergency action plan for sudden cardiac arrest at games and practices. AEDs should be placed so that the time from collapse to first shock is ideally under about:

    1. A. 10 to 12 minutes
    2. B. 3 to 5 minutes
    3. C. 15 to 20 minutes
    4. D. 25 to 30 minutes
    Show answer

    Answer: B. 3 to 5 minutes

    Survival from VF falls with every minute without a shock, so school and athletic emergency plans aim for a collapse-to-shock time of 3 to 5 minutes, which means AEDs on site, a trained responder, and a rehearsed plan rather than relying on EMS. Ten to 12 minutes is about the time it may take an ambulance to arrive and shock, and by then survival has fallen sharply. Fifteen to 20 minutes and 25 to 30 minutes would leave little chance of a good outcome even with bystander CPR. (Inter-association task force, Heart Rhythm 2007; AHA 2025 systems of care.)

14. Studies of public cardiac arrests in the United States have found that, compared with men, women who collapse in public are:

    1. A. More likely to get an AED shock
    2. B. Never found in a shockable rhythm
    3. C. Less likely to get bystander CPR
    4. D. Less likely to have an arrest
    Show answer

    Answer: C. Less likely to get bystander CPR

    Women who arrest in public receive bystander CPR and AED use less often than men, partly because of bystander concerns about touching or exposing the chest. Training emphasizes that CPR and AED pads should be applied without delay regardless of sex; clothing can be moved and replaced. Women can have shockable rhythms.

15. You arrive to find a bystander doing good compressions on a man in cardiac arrest. Your next step should be to:

    1. A. Keep compressions going while pads are applied
    2. B. Stop CPR to confirm pulselessness for 30 seconds
    3. C. Have the bystander stop so you can intubate
    4. D. Move the patient to the ambulance for CPR
    Show answer

    Answer: A. Keep compressions going while pads are applied

    Arriving crews should keep compressions continuous and get the defibrillator on as quickly as possible. A 30-second pause for a pulse check, or interrupting CPR to intubate, drops coronary perfusion pressure and delays the first shock.

16. To deliver effective adult chest compressions with the least fatigue, the rescuer should position his:

    1. A. Hands on the upper sternum, elbows bent
    2. B. Body to the side, pushing with the arms
    3. C. Knees far from the patient, leaning back
    4. D. Shoulders over his hands, elbows locked
    Show answer

    Answer: D. Shoulders over his hands, elbows locked

    Kneeling close to the patient with the shoulders directly over the hands and the elbows locked lets body weight drive compressions, giving adequate depth with less fatigue. Hands go on the lower half of the sternum. Bent elbows or pushing from the side relies on arm muscles and reduces depth.

17. AHA guidance tells lay rescuers to begin CPR when an adult is:

    1. A. Without a pulse on a carotid pulse check
    2. B. Unresponsive and not breathing normally
    3. C. Cyanotic with fixed, dilated pupils
    4. D. Unresponsive for over 2 minutes
    Show answer

    Answer: B. Unresponsive and not breathing normally

    Lay rescuers are not taught to check a pulse because they often misjudge it; unresponsiveness with absent or abnormal breathing is enough to start CPR. Waiting for cyanosis or a set time delays CPR when it helps most.

18. A bystander worries that compressions could hurt someone who is not actually in cardiac arrest. The best guidance is that:

    1. A. Compressions should wait for a pulse check
    2. B. Rib fractures in that case are usually fatal
    3. C. CPR should wait until an AED advises it
    4. D. Serious injury from CPR in that case is rare
    Show answer

    Answer: D. Serious injury from CPR in that case is rare

    Studies of people who received bystander CPR but were not in arrest show serious injury is uncommon, so the benefit of starting CPR far outweighs the risk. Waiting for a pulse check or an AED delays CPR for the many people who are truly in arrest.

19. Survival to hospital discharge after EMS-treated adult out-of-hospital cardiac arrest in the United States is roughly:

    1. A. About 1%
    2. B. About 30%
    3. C. About 10%
    4. D. About 50%
    Show answer

    Answer: C. About 10%

    National registry data (CARES) show overall survival to discharge near 9% to 10%, much higher in witnessed VF with bystander CPR. Figures of 30% or more apply only to the most favorable subgroups, such as witnessed VF arrests in strong systems.

20. A woman alone at home with a cell phone finds her father unresponsive and not breathing normally. The dispatcher should first have her:

    1. A. Use speakerphone and start compressions
    2. B. Hang up and search the house for an AED
    3. C. Go to the door and wait to guide EMS
    4. D. Check his wrist pulse for one full minute
    Show answer

    Answer: A. Use speakerphone and start compressions

    A speakerphone lets the dispatcher coach compressions while the caller stays with the patient, and compressions should not wait. Leaving to look for an AED or to wait at the door leaves the patient with no blood flow for minutes.

21. Bystander CPR improves survival from cardiac arrest mainly by:

    1. A. Converting VF back into a normal perfusing rhythm
    2. B. Keeping some blood flow to the heart and brain
    3. C. Fully oxygenating the blood with each breath
    4. D. Removing the need for later defibrillation
    Show answer

    Answer: B. Keeping some blood flow to the heart and brain

    Compressions generate enough coronary and cerebral flow to slow ischemic injury and keep VF shockable until a defibrillator arrives. CPR alone rarely converts VF; that requires a shock.

22. An off-duty paramedic sees a man collapse in a restaurant. An AED hangs on the wall 30 meters away, and another bystander is nearby. The best action is to:

    1. A. Get the AED yourself before starting any CPR
    2. B. Give two breaths, then check for a carotid pulse
    3. C. Start CPR and send the bystander for the AED
    4. D. Have the bystander call 9-1-1 and wait for EMS
    Show answer

    Answer: C. Start CPR and send the bystander for the AED

    With a second person present, the paramedic should begin compressions at once while the bystander calls 9-1-1 and brings the AED. Leaving the patient alone to get the AED is reasonable only for a lone rescuer.

23. Compared with arrests at home, arrests in public places more often present with:

    1. A. A shockable initial rhythm
    2. B. Asystole as the first rhythm
    3. C. A longer EMS response time
    4. D. An unwitnessed collapse
    Show answer

    Answer: A. A shockable initial rhythm

    Public arrests are more often witnessed, get earlier CPR, and involve people who are younger and more active, so VF is found more often. Arrests at home are more often unwitnessed and present in asystole or PEA.

24. Communities with the highest survival rates from out-of-hospital cardiac arrest typically have:

    1. A. More paramedics assigned to each ambulance
    2. B. Routine field intubation in every arrest
    3. C. Rapid transport with CPR performed en route
    4. D. High rates of bystander CPR and AED use
    Show answer

    Answer: D. High rates of bystander CPR and AED use

    The links that happen before ALS arrives, especially bystander CPR and early defibrillation, account for most of the variation in survival among communities. Early intubation and rapid transport have not been shown to drive survival.

25. A 50-year-old man suddenly collapses, has a brief episode of generalized jerking, and then lies still with occasional gasps. You should suspect:

    1. A. A seizure now in the postictal phase
    2. B. A simple faint that will resolve supine
    3. C. Hypoglycemia with a focal seizure
    4. D. Cardiac arrest with anoxic jerking
    Show answer

    Answer: D. Cardiac arrest with anoxic jerking

    Brief seizure-like activity is common at the moment of cardiac arrest as cerebral blood flow stops, and gasps after it suggest agonal breathing. Mistaking this for a postictal state delays CPR; check responsiveness, breathing, and pulse quickly and start compressions.