ACLS Practice Test: Video 2 Answers (24 Questions) — Questions and Answers

Question 1: During ACLS training, which rhythm requires immediate defibrillation as the first intervention?

Ventricular fibrillation (Correct answer)
Pulseless electrical activity
Asystole
Sinus bradycardia

Correct answer: Ventricular fibrillation

Ventricular fibrillation is a shockable rhythm that requires immediate defibrillation to restore organized electrical activity.

Question 2: Adult chest compressions are performed as follows:

Approximately 100–120 compressions per minute (Correct answer)
A rate of 80 to 100 compressions per minute.
Around 60–80 compressions per minute
A minimum of 80 compressions per minute

Correct answer: Approximately 100–120 compressions per minute

For adult chest compressions, ACLS guidelines recommend a rate of approximately 100–120 compressions per minute. This rate, combined with adequate depth (at least 2 inches or 5 cm) and full chest recoil, is crucial for optimizing blood flow to the brain and heart during cardiac arrest. Maintaining this rate helps ensure continuous and effective perfusion.

Question 3: A bag valve mask is used to ventilate an adult patient who is in respiratory arrest and has a pulse:

10 to 12 times per minute (Correct answer)
8 to 10 times per minute
12 to 14 times per minute
14 to 16 times per minute

Correct answer: 10 to 12 times per minute

For an adult patient in respiratory arrest who still has a pulse, the recommended ventilation rate using a bag-valve-mask is one breath every 5 to 6 seconds, which equates to 10 to 12 breaths per minute. This rate provides adequate oxygenation and ventilation without causing hyperventilation, which can negatively impact cardiac output and cerebral blood flow.

Question 4: When providing basic life support to an adult, the proper procedure is:

ABC - Airway, Breathing, Compressions
ACB - Airway, Compressions, Breathing
CAB - Compressions, Airway, Breathing (Correct answer)
BCA - Breathing, Compressions, Airway

Correct answer: CAB - Compressions, Airway, Breathing

The proper sequence for adult basic life support (BLS) is C-A-B: Chest Compressions, Airway, then Breathing. This sequence prioritizes immediate chest compressions to maintain vital organ perfusion, as delays in compressions significantly reduce survival rates. Establishing an airway and providing breaths follow after initiating compressions.

Question 5: During ACLS megacode practice, when should chest compressions be paused?

Every 1 minute to reassess rhythm
Only to deliver a shock or check pulse after rhythm change (Correct answer)
Whenever a medication is being administered
Every time a rescuer change occurs

Correct answer: Only to deliver a shock or check pulse after rhythm change

Compressions should be paused only to deliver a defibrillation shock or to check for a pulse after a rhythm change suggesting ROSC.

Question 6: A patient has a heart rate of 160 bpm with a narrow QRS complex and is hemodynamically stable. What is the first-line treatment?

Immediate synchronized cardioversion
Vagal maneuvers (Correct answer)
Amiodarone 150 mg IV over 10 minutes
Adenosine 12 mg IV push

Correct answer: Vagal maneuvers

Vagal maneuvers (e.g., Valsalva, carotid sinus massage) are the first-line treatment for stable narrow-complex tachycardia.

Question 7: During the bradycardia algorithm, atropine fails to increase the heart rate. What is the next intervention?

Adenosine 6 mg IV push
Synchronized cardioversion
Repeat atropine 1 mg IV
Transcutaneous pacing or dopamine/epinephrine infusion (Correct answer)

Correct answer: Transcutaneous pacing or dopamine/epinephrine infusion

If atropine is ineffective for symptomatic bradycardia, transcutaneous pacing or vasopressor infusion (dopamine or epinephrine) should be initiated.

Question 8: What is the maximum total dose of atropine recommended in the ACLS bradycardia algorithm?

5 mg
3 mg (Correct answer)
2 mg
1 mg

Correct answer: 3 mg

The maximum total dose of atropine in the ACLS bradycardia algorithm is 3 mg (given as 0.5 mg doses every 3–5 minutes).

Question 9: Which of the following is NOT a sign of hemodynamic instability requiring immediate intervention in tachycardia?

Hypotension (BP < 90 mmHg)
Acute pulmonary edema
Altered mental status
Heart rate of 110 bpm at rest (Correct answer)

Correct answer: Heart rate of 110 bpm at rest

A heart rate of 110 bpm alone does not constitute instability; signs like hypotension, altered mentation, and pulmonary edema indicate instability.

Question 10: A patient presents with atrial fibrillation with rapid ventricular response at 145 bpm, BP 88/60. What is the most appropriate next step?

Rate control with diltiazem IV
Rhythm control with oral flecainide
Anticoagulation with heparin
Synchronized cardioversion (Correct answer)

Correct answer: Synchronized cardioversion

Hemodynamically unstable atrial fibrillation with rapid ventricular response requires immediate synchronized cardioversion.

Question 11: A patient presents with chest pain and an ECG showing ST elevation in leads II, III, and aVF. Which coronary artery is most likely occluded?

Left anterior descending artery
Right coronary artery (Correct answer)
Left circumflex artery
Left main coronary artery

Correct answer: Right coronary artery

ST elevation in leads II, III, and aVF indicates an inferior STEMI, most commonly caused by occlusion of the right coronary artery.

Question 12: Which biomarker is most specific for myocardial injury and is the preferred marker for diagnosing ACS?

Creatine kinase (CK-MB)
Myoglobin
Troponin I or Troponin T (Correct answer)
Lactate dehydrogenase (LDH)

Correct answer: Troponin I or Troponin T

Cardiac troponin I and T are the most sensitive and specific biomarkers for myocardial injury and are the preferred markers for ACS diagnosis.

Question 13: A patient with NSTEMI has ongoing chest pain despite aspirin, heparin, and nitroglycerin. What is the next best step?

Immediate fibrinolytic therapy
Discontinue heparin and observe
Add a P2Y12 inhibitor such as ticagrelor or clopidogrel (Correct answer)
Administer atropine 0.5 mg IV

Correct answer: Add a P2Y12 inhibitor such as ticagrelor or clopidogrel

Dual antiplatelet therapy with aspirin plus a P2Y12 inhibitor (ticagrelor, clopidogrel, or prasugrel) is indicated for NSTEMI management.

Question 14: Which of the following findings on ECG is most consistent with posterior STEMI?

ST depression with tall R wave in V1–V2 (Correct answer)
Diffuse ST elevation with PR depression
ST elevation in V1–V4
New left bundle branch block

Correct answer: ST depression with tall R wave in V1–V2

Posterior STEMI manifests as ST depression with tall, broad R waves in leads V1–V2, representing a mirror image of posterior wall injury.

Question 15: How long should a patient be suctioned for in order to prevent hypoxia?

Not more than 35 seconds
Not more than 5 seconds
Not more than 15 seconds (Correct answer)
Not more than 25 seconds

Correct answer: Not more than 15 seconds

Suctioning removes oxygen from the airway along with secretions, which can quickly lead to hypoxia. To minimize the risk of desaturation and adverse effects in an adult patient, each suctioning attempt should be limited to a brief duration, typically no more than 15 seconds. This allows for effective clearing of the airway while preventing significant oxygen deprivation.

Question 16: Which item from the list below can be used to stop poisons from entering the bloodstream?

Magnesium sulfide
Calcium carbonate
Activated charcoal (Correct answer)
Oxygen

Correct answer: Activated charcoal

Activated charcoal is a highly effective adsorbent that can bind to many toxins and drugs in the gastrointestinal tract. By forming a complex with these substances, it prevents their absorption into the bloodstream, thereby reducing systemic toxicity. It is a common and important intervention in the management of oral poisonings.

Question 17: What is the cardiac output of a patient with a stroke volume of 80 mL and a heart rate of 60?

4800mLs (Correct answer)
480mLs
1.33mLs
140mLs

Correct answer: 4800mLs

Cardiac output (CO) is calculated by multiplying the stroke volume (SV) by the heart rate (HR). In this scenario, the stroke volume is 80 mL and the heart rate is 60 bpm. Therefore, CO = 80 mL/beat * 60 beats/minute = 4800 mL/minute.

Question 18: Which of the following symptoms does a tension pneumothorax not exhibit?

Subcutaneous emphysema
Hypertension (Correct answer)
Jugular venous distension
Dyspnea

Correct answer: Hypertension

A tension pneumothorax results from air accumulating in the pleural space, which compresses the lung and shifts mediastinal structures, impairing venous return to the heart. This leads to a significant decrease in cardiac output and systemic hypotension, not hypertension. Dyspnea, jugular venous distension (JVD), and subcutaneous emphysema are all expected findings due to the compromised respiratory and circulatory function.

Question 19: What reduces when preload is decreased by hypovolemia?

Synapses output
Synapses input
Cardiac output (Correct answer)
Cardiac input

Correct answer: Cardiac output

Preload refers to the volume of blood stretching the ventricular muscle fibers at the end of diastole. Hypovolemia, or low blood volume, directly reduces the amount of blood returning to the heart, thereby decreasing preload. According to the Frank-Starling mechanism, a reduced preload leads to a decreased stroke volume, which in turn lowers the overall cardiac output.

Question 20: During stroke assessment, a patient scores 4 points on the Los Angeles Prehospital Stroke Screen (LAPSS). What does this indicate?

Stroke is unlikely; reassess for other diagnoses
Hemorrhagic stroke is confirmed
The patient requires only aspirin therapy
Stroke is likely; activate the stroke team immediately (Correct answer)

Correct answer: Stroke is likely; activate the stroke team immediately

A positive LAPSS (all criteria met) indicates high likelihood of stroke, prompting immediate stroke team activation and transport to a stroke center.

Question 21: A 78-year-old patient with known atrial fibrillation on warfarin presents with acute ischemic stroke. INR is 1.7. Is IV tPA indicated?

No, any anticoagulant use is an absolute contraindication
Yes, if onset was less than 3 hours ago
Yes, INR < 2.0 permits tPA administration (Correct answer)
No, INR > 1.7 is a contraindication to tPA

Correct answer: Yes, INR < 2.0 permits tPA administration

IV tPA can be given if INR is ≤ 1.7; an INR > 1.7 in a patient on warfarin is a contraindication.

Question 22: What is the maximum time window for mechanical thrombectomy in selected patients with large vessel occlusion and favorable imaging?

16 hours from onset
6 hours from onset
24 hours from onset (Correct answer)
4.5 hours from onset

Correct answer: 24 hours from onset

Trials (DAWN, DEFUSE 3) support mechanical thrombectomy up to 24 hours from last known well in selected patients with target mismatch on imaging.

Question 23: Which blood pressure threshold must be achieved and maintained BEFORE administering IV alteplase for acute ischemic stroke?

< 220/120 mmHg
< 185/110 mmHg (Correct answer)
< 160/90 mmHg
< 140/80 mmHg

Correct answer: < 185/110 mmHg

BP must be < 185/110 mmHg before alteplase administration and maintained < 180/105 mmHg for at least 24 hours afterward.

Question 24: Which finding on non-contrast CT head is an absolute contraindication to IV tPA in acute ischemic stroke?

Loss of gray-white differentiation in basal ganglia
Hemorrhagic transformation (Correct answer)
Early ischemic changes in less than 1/3 of MCA territory
Hyperdense MCA sign

Correct answer: Hemorrhagic transformation

Any intracranial hemorrhage on CT is an absolute contraindication to IV tPA administration.

ACLS Practice Test: Video 2 Answers (24 Questions)

During ACLS training, which rhythm requires immediate defibrillation as the first intervention?

What Practice Test Geeks adds beyond an AI chat for ACLS

An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:

A timed, full-length ACLS mock exam — 50 questions in 60 minutes with a 84% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
A fixed ACLS question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
A printable ACLS cheat sheet you can print or save as a PDF.
ACLS flashcards built from the same question bank.

Start the Timed ACLS Mock Exam →

These practice questions were written with AI tools. They are not real exam questions. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy

Sources & references

Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy

cpr.heart.org — Fees, renewal, test delivery, score validity, eligibility · verified Oct 2026