BLS Chain of Survival 5 — Questions and Answers
Question 1: Which factor has the GREATEST impact on survival when the first two links of the Chain of Survival (recognition/activation and early CPR) are already in place?
- Time to defibrillation (Correct answer)
- Patient age
- Bystander CPR rate
- Number of EMS responders
Correct answer: Time to defibrillation
When CPR is underway, time to defibrillation becomes the dominant determinant of survival for shockable rhythms.
Question 2: A cardiac arrest victim has ventricular fibrillation (VF). CPR is in progress. The AED analyzes and advises 'No shock recommended.' What should the rescuer do?
- Immediately resume CPR and recheck every 2 minutes (Correct answer)
- Continue shocking until VF is converted
- Stop CPR and wait for EMS
- Administer a precordial thump
Correct answer: Immediately resume CPR and recheck every 2 minutes
A 'no shock' advisory means the rhythm is non-shockable; CPR must continue to maintain perfusion and rhythms are reassessed every 2-minute cycle.
Question 3: Which statement best explains why CPR alone rarely restores a normal heart rhythm in ventricular fibrillation?
- CPR maintains perfusion but cannot terminate the chaotic electrical activity of VF — only defibrillation can (Correct answer)
- CPR provides oxygenation sufficient to reverse VF over time
- VF is not a shockable rhythm and therefore does not respond to defibrillation
- CPR is designed only to support breathing, not cardiac function
Correct answer: CPR maintains perfusion but cannot terminate the chaotic electrical activity of VF — only defibrillation can
CPR sustains blood flow to the heart and brain but cannot reorganize the disorganized electrical signals of VF; a defibrillatory shock is required.
Question 4: A hospital implements a rapid response team (RRT) to evaluate deteriorating patients before cardiac arrest. Which Chain of Survival link does this MOST directly support?
- Surveillance and prevention (in-hospital first link) (Correct answer)
- Early CPR
- Rapid defibrillation
- Post-cardiac arrest care
Correct answer: Surveillance and prevention (in-hospital first link)
RRTs are a surveillance and prevention strategy unique to the in-hospital chain, intervening before arrest occurs.
Question 5: Which of the following BEST explains why the Chain of Survival is called a 'chain' and not a 'checklist'?
- Each link depends on the previous one, and a break in any link weakens the entire system (Correct answer)
- The links can be performed in any order depending on rescuer preference
- Only one link needs to function well to achieve survival
- The chain metaphor indicates that only trained professionals should participate
Correct answer: Each link depends on the previous one, and a break in any link weakens the entire system
Like a physical chain, the system is only as strong as its weakest link — delays or failures at any step reduce the chance of survival.
Question 6: A 45-year-old woman survives cardiac arrest and achieves ROSC. She remains comatose. Which post-cardiac arrest care intervention is recommended to protect neurological outcomes?
- Targeted temperature management (TTM) at 32–36°C for at least 24 hours (Correct answer)
- Immediate rewarming to 38°C
- Therapeutic hyperoxia with 100% oxygen continuously
- Withholding all medications until the patient regains consciousness
Correct answer: Targeted temperature management (TTM) at 32–36°C for at least 24 hours
TTM at 32–36°C for at least 24 hours reduces cerebral metabolic demand and improves neurological recovery in comatose post-arrest patients.
Question 7: Which community-level intervention has been shown to MOST effectively improve outcomes by strengthening multiple links in the out-of-hospital Chain of Survival simultaneously?
- Public access defibrillation (PAD) programs combined with CPR training (Correct answer)
- Increasing the number of hospital beds
- Reducing the number of 911 call centers to streamline dispatch
- Restricting AED use to licensed healthcare providers
Correct answer: Public access defibrillation (PAD) programs combined with CPR training
PAD programs place AEDs in public locations and pair them with CPR training, simultaneously strengthening the early CPR and rapid defibrillation links.
BLS Chain of Survival 5
Which factor has the GREATEST impact on survival when the first two links of the Chain of Survival (recognition/activation and early CPR) are already in place?