ACLS Advanced Cardiac Life
Support: Master Algorithmic
Management & Critical Cardiac Care
Practice Questions & Detailed
Explanations
Subject: Advanced Cardiovascular Life Support (ACLS) - Core
Algorithms and Advanced Clinical Management
Question 1: A 68-year-old patient with a history of heart failure presents with wide-complex
tachycardia (QRS 0.16s), monomorphic, regular rhythm at 170 bpm. The patient is currently
asymptomatic and hemodynamically stable. After attempting vagal maneuvers without success,
what is the most appropriate next therapeutic action according to the 2026 ACLS guidelines?
A) Administer Adenosine 6 mg rapid IV push.
B) Perform immediate synchronized cardioversion at 100J.
C) Administer an infusion of Amiodarone 150 mg over 10 minutes.
D) Administer Procainamide 20-50 mg/min until the arrhythmia suppresses.
Correct Answer: C) Administer an infusion of Amiodarone 150 mg over 10 minutes.
Explanation: For stable wide-complex tachycardia, differentiation between VT and SVT with
aberrancy is crucial. In the absence of a confirmed supraventricular diagnosis, VT should be
assumed. Amiodarone is the preferred antiarrhythmic infusion for stable VT. Adenosine is
ineffective (and potentially contraindicated) for true VT. Cardioversion is reserved for unstable
patients. Procainamide is an alternative, but amiodarone is more widely utilized in standard
algorithmic pathways for these parameters.
Question 2: You are treating a patient in pulseless electrical activity (PEA) with a rate of 40 bpm.
Despite high-quality CPR and the second dose of epinephrine, the rhythm transitions to a
narrow-complex asystole. What is the most significant clinical implication of this rhythm shift in
the context of the H's and T's?
A) The patient is likely developing a terminal rhythm, and resuscitation efforts should be
terminated.
,B) The shift indicates a high probability of hyperkalemia; immediate calcium administration is
required.
C) The transition does not change the management strategy; prioritize high-quality CPR and
search for underlying reversible causes.
D) The patient requires immediate transcutaneous pacing to regain an organized cardiac output.
Correct Answer: C) The transition does not change the management strategy; prioritize
high-quality CPR and search for underlying reversible causes.
Explanation: In both PEA and asystole, the treatment algorithm is identical: high-quality CPR,
airway management, and epinephrine administration. The rhythm morphology (narrow vs. wide)
does not alter the ACLS management path, nor does it override the necessity of identifying the
underlying H's and T's. Pacing is not indicated for asystole or PEA.
Question 3: During the resuscitation of a patient with VF, the team is struggling with "pitfall"
errors during the 2-minute pulse checks. According to 2026 high-performance team standards,
which of the following best minimizes compression interruptions?
A) Pausing compressions 10 seconds before the rhythm check to prepare the defibrillator.
B) Assessing the rhythm via the defibrillator’s "hands-off" analysis feature while the compressor
continues compressions.
C) Analyzing the rhythm for 5 seconds and checking for a pulse for 5 seconds simultaneously.
D) Switching compressors precisely every 2 minutes while the rhythm is analyzed by a separate
provider.
Correct Answer: D) Switching compressors precisely every 2 minutes while the rhythm is
analyzed by a separate provider.
Explanation: Minimizing interruptions is vital to maintain coronary perfusion pressure. Standard
practice dictates that rhythm analysis and pulse checks occur during the transition between
compressors. Pausing early (A) decreases perfusion. Analysis while compressing (B) is
technically difficult due to artifact. D represents the most efficient way to maintain the 10-second
limit for interruptions.
Question 4: A 55-year-old patient with STEMI develops symptomatic bradycardia (HR 42 bpm)
with hypotension (BP 88/50 mmHg). Atropine 1 mg has been administered twice with no effect.
What is the priority intervention to bridge this patient to definitive care?
A) Begin an Epinephrine infusion at 2-10 mcg/min.
B) Initiate Transcutaneous Pacing (TCP) at a rate of 80 bpm.
,C) Administer Glucagon to counteract potential beta-blocker toxicity.
D) Perform urgent synchronized cardioversion.
Correct Answer: B) Initiate Transcutaneous Pacing (TCP) at a rate of 80 bpm.
Explanation: When atropine is ineffective for hemodynamically unstable bradycardia, TCP is the
definitive ACLS bridge. The capture rate should be set to provide an adequate cardiac output,
usually 70-80 bpm. Epinephrine (A) is a secondary choice if pacing is unavailable or ineffective.
Cardioversion (D) is indicated for tachycardia, not bradycardia.
Question 5: A patient is post-ROSC after a 15-minute cardiac arrest. ETCO2 is currently 30
mmHg, and oxygen saturation is 96%. The patient is comatose. What is the current evidence-
based recommendation for the oxygenation and ventilation strategy?
A) Hyperventilate to reach an ETCO2 of 25 mmHg to reduce intracranial pressure.
B) Maintain normocapnia (ETCO2 35-45 mmHg) and titrate FIO2 to maintain SpO2 ≥ 94%.
C) Administer 100% FIO2 for the first 24 hours to ensure cerebral oxygenation.
D) Extubate immediately if the patient demonstrates a gag reflex.
Correct Answer: B) Maintain normocapnia (ETCO2 35-45 mmHg) and titrate FIO2 to
maintain SpO2 ≥ 94%.
Explanation: Hyperventilation causes cerebral vasoconstriction, worsening neurological
outcomes. The goal is to provide adequate oxygenation (titrating FIO2) and prevent hypocapnia.
Maintaining normal CO2 levels is protective for the post-arrest brain.
Question 6: Which of the following scenarios in a cardiac arrest setting is most likely to
necessitate the use of the "Refractory VF" protocol involving dual-sequential defibrillation or
alternative antiarrhythmics?
A) VF recurring after 1 shock and no medication.
B) VF persisting after 3 shocks and 300 mg of Amiodarone.
C) A patient with known prolonged QT syndrome presenting in polymorphic VT.
D) A patient presenting in PEA that converts to VF after 10 minutes of CPR.
Correct Answer: B) VF persisting after 3 shocks and 300 mg of Amiodarone.
Explanation: Refractory VF is defined as persistence despite multiple shocks and antiarrhythmic
therapy. While dual-sequential defibrillation is debated, the clinical threshold for considering
, escalated measures is typically defined by failure to convert after the standard antiarrhythmic
dose and multiple shocks.
Question 7: A patient in the ICU develops sudden cardiac arrest. The monitor shows organized
electrical activity, but there is no palpable pulse. A point-of-care ultrasound (POCUS) reveals an
empty left ventricle and a hyperdynamic heart. Which H's or T's is this most suggestive of?
A) Tension Pneumothorax.
B) Cardiac Tamponade.
C) Hypovolemia.
D) Myocardial Infarction.
Correct Answer: C) Hypovolemia.
Explanation: An empty left ventricle (a "kissing wall" appearance on ultrasound) combined with
a hyperdynamic heart is the classic sonographic finding for severe hypovolemia. Tamponade
would show fluid around the heart, and MI might show regional wall motion abnormalities.
Question 8: In the management of a patient in stable SVT, if Adenosine is contraindicated due to
severe asthma (bronchospastic potential), what is the most appropriate pharmacological
alternative?
A) Amiodarone 150 mg IV.
B) Diltiazem 15-20 mg IV.
C) Atropine 0.5 mg IV.
D) Digoxin 0.25 mg IV.
Correct Answer: B) Diltiazem 15-20 mg IV.
Explanation: Non-dihydropyridine calcium channel blockers like diltiazem are the preferred
second-line agents for SVT when adenosine is ineffective or contraindicated. Amiodarone is less
effective for acute SVT termination. Atropine increases heart rate and is contraindicated.
Question 9: What is the recommended dose of Epinephrine for an adult patient in cardiac arrest,
and what is the primary physiological justification for its administration timing?
A) 1 mg every 3-5 minutes to decrease systemic vascular resistance (SVR).
B) 1 mg every 3-5 minutes to increase coronary perfusion pressure (CPP).
Support: Master Algorithmic
Management & Critical Cardiac Care
Practice Questions & Detailed
Explanations
Subject: Advanced Cardiovascular Life Support (ACLS) - Core
Algorithms and Advanced Clinical Management
Question 1: A 68-year-old patient with a history of heart failure presents with wide-complex
tachycardia (QRS 0.16s), monomorphic, regular rhythm at 170 bpm. The patient is currently
asymptomatic and hemodynamically stable. After attempting vagal maneuvers without success,
what is the most appropriate next therapeutic action according to the 2026 ACLS guidelines?
A) Administer Adenosine 6 mg rapid IV push.
B) Perform immediate synchronized cardioversion at 100J.
C) Administer an infusion of Amiodarone 150 mg over 10 minutes.
D) Administer Procainamide 20-50 mg/min until the arrhythmia suppresses.
Correct Answer: C) Administer an infusion of Amiodarone 150 mg over 10 minutes.
Explanation: For stable wide-complex tachycardia, differentiation between VT and SVT with
aberrancy is crucial. In the absence of a confirmed supraventricular diagnosis, VT should be
assumed. Amiodarone is the preferred antiarrhythmic infusion for stable VT. Adenosine is
ineffective (and potentially contraindicated) for true VT. Cardioversion is reserved for unstable
patients. Procainamide is an alternative, but amiodarone is more widely utilized in standard
algorithmic pathways for these parameters.
Question 2: You are treating a patient in pulseless electrical activity (PEA) with a rate of 40 bpm.
Despite high-quality CPR and the second dose of epinephrine, the rhythm transitions to a
narrow-complex asystole. What is the most significant clinical implication of this rhythm shift in
the context of the H's and T's?
A) The patient is likely developing a terminal rhythm, and resuscitation efforts should be
terminated.
,B) The shift indicates a high probability of hyperkalemia; immediate calcium administration is
required.
C) The transition does not change the management strategy; prioritize high-quality CPR and
search for underlying reversible causes.
D) The patient requires immediate transcutaneous pacing to regain an organized cardiac output.
Correct Answer: C) The transition does not change the management strategy; prioritize
high-quality CPR and search for underlying reversible causes.
Explanation: In both PEA and asystole, the treatment algorithm is identical: high-quality CPR,
airway management, and epinephrine administration. The rhythm morphology (narrow vs. wide)
does not alter the ACLS management path, nor does it override the necessity of identifying the
underlying H's and T's. Pacing is not indicated for asystole or PEA.
Question 3: During the resuscitation of a patient with VF, the team is struggling with "pitfall"
errors during the 2-minute pulse checks. According to 2026 high-performance team standards,
which of the following best minimizes compression interruptions?
A) Pausing compressions 10 seconds before the rhythm check to prepare the defibrillator.
B) Assessing the rhythm via the defibrillator’s "hands-off" analysis feature while the compressor
continues compressions.
C) Analyzing the rhythm for 5 seconds and checking for a pulse for 5 seconds simultaneously.
D) Switching compressors precisely every 2 minutes while the rhythm is analyzed by a separate
provider.
Correct Answer: D) Switching compressors precisely every 2 minutes while the rhythm is
analyzed by a separate provider.
Explanation: Minimizing interruptions is vital to maintain coronary perfusion pressure. Standard
practice dictates that rhythm analysis and pulse checks occur during the transition between
compressors. Pausing early (A) decreases perfusion. Analysis while compressing (B) is
technically difficult due to artifact. D represents the most efficient way to maintain the 10-second
limit for interruptions.
Question 4: A 55-year-old patient with STEMI develops symptomatic bradycardia (HR 42 bpm)
with hypotension (BP 88/50 mmHg). Atropine 1 mg has been administered twice with no effect.
What is the priority intervention to bridge this patient to definitive care?
A) Begin an Epinephrine infusion at 2-10 mcg/min.
B) Initiate Transcutaneous Pacing (TCP) at a rate of 80 bpm.
,C) Administer Glucagon to counteract potential beta-blocker toxicity.
D) Perform urgent synchronized cardioversion.
Correct Answer: B) Initiate Transcutaneous Pacing (TCP) at a rate of 80 bpm.
Explanation: When atropine is ineffective for hemodynamically unstable bradycardia, TCP is the
definitive ACLS bridge. The capture rate should be set to provide an adequate cardiac output,
usually 70-80 bpm. Epinephrine (A) is a secondary choice if pacing is unavailable or ineffective.
Cardioversion (D) is indicated for tachycardia, not bradycardia.
Question 5: A patient is post-ROSC after a 15-minute cardiac arrest. ETCO2 is currently 30
mmHg, and oxygen saturation is 96%. The patient is comatose. What is the current evidence-
based recommendation for the oxygenation and ventilation strategy?
A) Hyperventilate to reach an ETCO2 of 25 mmHg to reduce intracranial pressure.
B) Maintain normocapnia (ETCO2 35-45 mmHg) and titrate FIO2 to maintain SpO2 ≥ 94%.
C) Administer 100% FIO2 for the first 24 hours to ensure cerebral oxygenation.
D) Extubate immediately if the patient demonstrates a gag reflex.
Correct Answer: B) Maintain normocapnia (ETCO2 35-45 mmHg) and titrate FIO2 to
maintain SpO2 ≥ 94%.
Explanation: Hyperventilation causes cerebral vasoconstriction, worsening neurological
outcomes. The goal is to provide adequate oxygenation (titrating FIO2) and prevent hypocapnia.
Maintaining normal CO2 levels is protective for the post-arrest brain.
Question 6: Which of the following scenarios in a cardiac arrest setting is most likely to
necessitate the use of the "Refractory VF" protocol involving dual-sequential defibrillation or
alternative antiarrhythmics?
A) VF recurring after 1 shock and no medication.
B) VF persisting after 3 shocks and 300 mg of Amiodarone.
C) A patient with known prolonged QT syndrome presenting in polymorphic VT.
D) A patient presenting in PEA that converts to VF after 10 minutes of CPR.
Correct Answer: B) VF persisting after 3 shocks and 300 mg of Amiodarone.
Explanation: Refractory VF is defined as persistence despite multiple shocks and antiarrhythmic
therapy. While dual-sequential defibrillation is debated, the clinical threshold for considering
, escalated measures is typically defined by failure to convert after the standard antiarrhythmic
dose and multiple shocks.
Question 7: A patient in the ICU develops sudden cardiac arrest. The monitor shows organized
electrical activity, but there is no palpable pulse. A point-of-care ultrasound (POCUS) reveals an
empty left ventricle and a hyperdynamic heart. Which H's or T's is this most suggestive of?
A) Tension Pneumothorax.
B) Cardiac Tamponade.
C) Hypovolemia.
D) Myocardial Infarction.
Correct Answer: C) Hypovolemia.
Explanation: An empty left ventricle (a "kissing wall" appearance on ultrasound) combined with
a hyperdynamic heart is the classic sonographic finding for severe hypovolemia. Tamponade
would show fluid around the heart, and MI might show regional wall motion abnormalities.
Question 8: In the management of a patient in stable SVT, if Adenosine is contraindicated due to
severe asthma (bronchospastic potential), what is the most appropriate pharmacological
alternative?
A) Amiodarone 150 mg IV.
B) Diltiazem 15-20 mg IV.
C) Atropine 0.5 mg IV.
D) Digoxin 0.25 mg IV.
Correct Answer: B) Diltiazem 15-20 mg IV.
Explanation: Non-dihydropyridine calcium channel blockers like diltiazem are the preferred
second-line agents for SVT when adenosine is ineffective or contraindicated. Amiodarone is less
effective for acute SVT termination. Atropine increases heart rate and is contraindicated.
Question 9: What is the recommended dose of Epinephrine for an adult patient in cardiac arrest,
and what is the primary physiological justification for its administration timing?
A) 1 mg every 3-5 minutes to decrease systemic vascular resistance (SVR).
B) 1 mg every 3-5 minutes to increase coronary perfusion pressure (CPP).
