ACLS Exam Questions & Answers 2026 (21–30)

✓ Correct answer: A. 5 to 6 seconds

When a patient is facing respiratory arrest but maintains a perfusing rhythm, it is crucial to administer rescue breaths at the right frequency to ensure adequate oxygenation. The correct frequency for administering rescue breaths in this situation is 1 breath every 5 to 6 seconds. This timing allows for effective ventilation and prevents hypoxia.<br/><br/>Option B (3 to 5 seconds) is incorrect. Administering rescue breaths at a frequency of 3 to 5 seconds may not provide enough time for each breath to be fully delivered and for proper gas exchange to occur. This could result in inadequate oxygenation for the patient.<br/><br/>Option C (6 to 10 seconds) is also incorrect. Administering rescue breaths at a frequency of 6 to 10 seconds may lead to delays in oxygenation and could compromise the patient's respiratory function. This timing interval is longer than recommended for maintaining adequate ventilation.<br/><br/>Option D (8 to 10 seconds) is incorrect as well. Administering rescue breaths at a frequency of 8 to 10 seconds may result in prolonged periods without oxygenation, which can be detrimental to the patient's overall condition. This timing interval is too long for ensuring effective gas exchange.<br/><br/>Therefore, the correct answer is A) 5 to 6 seconds, as this frequency allows for proper ventilation and oxygenation in patients facing respiratory arrest while maintaining a perfusing rhythm.

✓ Correct answer: C. To increase return of spontaneous circulation (ROSC)

The primary objective of administering epinephrine during cardiac arrest, specifically in a patient with ventricular fibrillation (VF), is to increase the likelihood of return of spontaneous circulation (ROSC) (option C).<br/><br/>Epinephrine is a vasoconstrictor that increases blood pressure and coronary perfusion pressure, which can improve the chances of successful defibrillation and achieving ROSC.<br/><br/>While improving oxygenation (option A) is an essential aspect of resuscitation, epinephrine's primary role in VF cardiac arrest is to support circulation.<br/><br/>Restoring normal sinus rhythm (option B) may be a desired outcome, but epinephrine itself does not directly achieve this goal.<br/><br/>Reducing chest compression interruptions (option D) is crucial to maintaining high-quality CPR, but epinephrine administration is not directly related to chest compression interruptions.

✓ Correct answer: A. The fast or ineffective heartbeat reduces cardiac output.

Patients experiencing acute unstable tachycardia often exhibit changes in mental state and difficulty breathing due to the fast or ineffective heartbeat reducing cardiac output. When the heart beats too rapidly, it may not have enough time to fill up with enough blood before pumping it out. This results in a decrease in the amount of blood being pumped out of the heart with each beat, leading to a reduced cardiac output.<br/><br/>Option B (The fast heart rate leads to decreased vascular resistance) is incorrect. While an increase in heart rate may lead to a temporary decrease in vascular resistance, this is not the underlying explanation for the changes in mental state and difficulty breathing seen in patients with acute unstable tachycardia.<br/><br/>Option C (Low cardiac output leads to increased vagal tone) is also incorrect. Vagal tone refers to the activity of the vagus nerve, which helps regulate various bodily functions including heart rate. While low cardiac output may affect vagal tone, it is not the primary reason for the observed changes in mental state and difficulty breathing in patients with acute unstable tachycardia.<br/><br/>Option D (The fast heart rate causes increased intracranial pressure) is also incorrect. While it is true that certain conditions can cause an increase in intracranial pressure, such as a brain injury or tumor, the fast heart rate itself does not directly cause increased intracranial pressure. Therefore, it is not the underlying explanation for the changes seen in patients with acute unstable tachycardia.<br/><br/>In summary, the correct answer is A) The fast or ineffective heartbeat reduces cardiac output, which leads to the observed changes in mental state and difficulty breathing.

✓ Correct answer: B. Brain injury and cardiovascular stability.

After successful resuscitation from cardiac arrest, the patient's outcomes and survival during post-arrest treatment are largely determined by two critical factors: brain injury and cardiovascular stability (correct answer).<br/><br/>Brain injury refers to the extent of damage to the brain tissue that may have occurred during the period of low or no oxygen supply during the cardiac arrest. Adequate oxygenation and blood flow are essential to prevent brain damage and maintain neurological function.<br/><br/>Cardiovascular stability refers to the ability of the heart to maintain an adequate blood pressure and perfuse vital organs. It is crucial to ensure proper circulation and oxygen delivery to prevent organ dysfunction and failure during the post-arrest phase.

✓ Correct answer: C. Administration of heparin

Heparin is an anticoagulant medication that is commonly used in the treatment of ST-elevation myocardial infarction (STEMI) to prevent the formation of blood clots. It is typically administered after aspirin therapy has been initiated. Delaying the administration of heparin can increase the risk of further blood clotting and worsen the patient's condition, making it an inappropriate action to take before the patient arrives at the emergency department (ED).<br/><br/>Option A (Administration of sublingual nitroglycerin): Nitroglycerin, as mentioned earlier, is an important medication for relieving chest pain and improving blood flow to the heart in patients with STEMI. Therefore, administration of sublingual nitroglycerin is a necessary action and should not be withheld before the patient arrives at the ED. This option is incorrect.<br/><br/>Option C (Administration of morphine): Morphine is sometimes used to manage severe pain associated with STEMI. However, it should be administered cautiously and if necessary, to manage pain while waiting for further intervention. It is not a priority action to be taken before the patient arrives at the ED. Therefore, this option is incorrect.<br/><br/>Option D (Administration of aspirin): Aspirin is a crucial medication for reducing the risk of blood clotting and further damage to the heart muscle in patients with STEMI. It is one of the first-line treatments and should be administered as soon as possible. Delaying the initiation of aspirin therapy can have negative effects on patient outcomes. Therefore, this option is incorrect.<br/><br/>By analyzing the correct and incorrect answer options, it is evident that the attending ED physician should not recommend delaying the administration of aspirin therapy, withholding nitroglycerin administration, neglecting to suggest early cardiac catheterization, or failing to discuss the option of fibrinolytic therapy before the patient arrives at the ED. However, the administration of heparin is the correct action to be taken during the management of STEMI.

✓ Correct answer: A. Providing a communication board with pictures and symbols

For a patient with expressive aphasia and difficulty communicating, providing a communication board with pictures and symbols is an appropriate nursing intervention to support the patient's communication needs. A communication board allows the patient to point to pictures or symbols representing their needs, feelings, or questions. It facilitates nonverbal communication and helps the patient convey their thoughts effectively despite the expressive language difficulties.<br/><br/>Option A (Encouraging family members to interpret for the patient) may not be sufficient, as family members may not always understand the patient's needs fully. Communication boards are a more reliable means of supporting communication.<br/><br/>Option C (Using medical jargon and technical terms in conversations) should be avoided. Patients with aphasia may have difficulty understanding complex language, and using simpler language is more effective for communication.<br/><br/>Option D (Limiting nonverbal communication to avoid confusion) is not recommended. Nonverbal communication, such as gestures and facial expressions, can be essential for enhancing understanding and emotional expression in patients with aphasia.

✓ Correct answer: A. all of the above

Nitroglycerin is commonly used in the ACS (Acute Coronary Syndrome) protocol to relieve chest pain and improve blood flow to the heart. However, there are certain circumstances where the use of nitroglycerin may be contraindicated. Let's analyze each of the incorrect options and understand why they can prevent the use of nitroglycerin in the ACS protocol:<br/><br/>Option A) Hypotension: Hypotension refers to low blood pressure. Nitroglycerin is a vasodilator, meaning it relaxes and widens the blood vessels, which can potentially lower blood pressure. If a patient already has low blood pressure, the administration of nitroglycerin can further reduce their blood pressure to dangerous levels. Hence, hypotension is a circumstance that would prevent the use of nitroglycerin in the ACS protocol.<br/><br/>Option B) Right Ventricular Infarction: Right ventricular infarction is a condition where there is damage to the right ventricle of the heart due to a lack of blood supply. Nitroglycerin primarily acts on the coronary arteries to improve blood flow to the heart muscle. However, in right ventricular infarction, there may already be compromised blood flow to the right ventricle. Administering nitroglycerin in this situation can further decrease blood flow to the right ventricle, worsening the condition. Therefore, right ventricular infarction is a circumstance that would prevent the use of nitroglycerin in the ACS protocol.<br/><br/>Option C) Recent Phosphodiesterase Inhibitor Use: Phosphodiesterase inhibitors (such as sildenafil, tadalafil, vardenafil) are a class of medications used to treat erectile dysfunction and pulmonary hypertension. These medications also cause vasodilation and can lower blood pressure. Since nitroglycerin is also a vasodilator, combining it with recent phosphodiesterase inhibitor use can lead to a significant drop in blood pressure, which can be dangerous. Thus, recent phosphodiesterase inhibitor use is a circumstance that would prevent the use of nitroglycerin in the ACS protocol.<br/><br/>In summary, all of the above options (hypotension, right ventricular infarction, recent phosphodiesterase inhibitor use) can be circumstances that would prevent the use of nitroglycerin in the ACS protocol.

✓ Correct answer: E. Asystole

Asystole is a condition characterized by the absence of any discernible electrical activity in the heart. It is commonly known as "flatline" as it appears as a straight horizontal line on an ECG or rhythm strip. In asystole, there is no contraction or pumping action occurring in the heart, leading to a complete absence of cardiac output. This is a life-threatening condition and immediate resuscitation measures, such as cardiopulmonary resuscitation (CPR) and advanced cardiac life support (ACLS), are required to restore cardiac function.<br/><br/>Option A) Third-degree heart block: Third-degree heart block, also known as complete heart block, is a condition in which there is a complete dissociation between the atria and ventricles. This results in the atria and ventricles beating independently of each other. On an ECG or rhythm strip, third-degree heart block is characterized by a regular atrial rate and a regular ventricular rate, but the two rates are not in sync. This condition requires prompt medical intervention, such as a pacemaker, to maintain adequate heart rate and rhythm.<br/><br/>Option B) Sinus bradycardia: Sinus bradycardia is a condition in which the heart rate is slower than normal. It is characterized by a regular rhythm and a heart rate below 60 beats per minute in adults. On an ECG or rhythm strip, sinus bradycardia appears as normal sinus rhythm, but with a slower rate. Sinus bradycardia can be a normal variant, particularly in athletes, but can also be a sign of underlying medical conditions or medication side effects.<br/><br/>Option C) Ventricular tachycardia: Ventricular tachycardia is a rapid heart rhythm originating from the ventricles. It is characterized by a wide QRS complex on an ECG or rhythm strip. Ventricular tachycardia can be life-threatening, especially if it deteriorates into ventricular fibrillation, and requires immediate medical intervention, such as cardioversion or defibrillation.<br/><br/>Option D) SVT (supraventricular tachycardia): SVT is a broad term that encompasses several types of abnormal heart rhythms originating above the ventricles. It is characterized by a regular and rapid heart rate. On an ECG or rhythm strip, SVT appears as a narrow QRS complex. SVT usually occurs suddenly and resolves spontaneously, but may require medical treatment if symptoms are severe or persistent.<br/><br/>Option E) Atrial fibrillation: Atrial fibrillation is a chaotic and irregular heart rhythm originating from the atria. It is characterized by the absence of P waves and an irregularly irregular ventricular response on an ECG or rhythm strip. Atrial fibrillation can increase the risk of blood clots and strokes and requires medical management to control heart rate and restore normal sinus rhythm.<br/><br/>Option F) Second-degree heart block Type II: Second-degree heart block Type II is a condition in which some atrial impulses fail to conduct to the ventricles. On an ECG or rhythm strip, it is characterized by intermittent dropped QRS complexes. Second-degree heart block Type II is considered more severe than first-degree heart block and may progress to third-degree heart block.<br/><br/>Option G) Ventricular fibrillation: Ventricular fibrillation is a chaotic and disorganized heart rhythm originating from the ventricles. It is characterized by irregular, erratic, and rapid ventricular activity on an ECG or rhythm strip. Ventricular fibrillation is a life-threatening condition and requires immediate defibrillation to restore normal heart rhythm.<br/><br/>Option H) Atrial Flutter: Atrial flutter is a rapid heart rhythm originating from the atria. It is characterized by continuous sawtooth-like flutter waves on an ECG or rhythm strip. Atrial flutter can increase the risk of blood clots and strokes and requires medical management to control heart rate and restore normal sinus rhythm.<br/><br/>Option I) Sinus tachycardia: Sinus tachycardia is a physiological response to increased demand or stress. It is characterized by a regular rhythm and a heart rate above 100 beats per minute in adults. On an ECG or rhythm strip, sinus tachycardia appears as normal sinus rhythm, but with a faster rate. Sinus tachycardia is usually a benign condition and resolves once the underlying cause is addressed.<br/><br/>Option K) Second-degree heart block Type I: Second-degree heart block Type I, also known as Wenckebach block, is a condition in which there is progressive delay and eventual failure of atrial impulses to conduct to the ventricles. On an ECG or rhythm strip, it is characterized by a series of dropped QRS complexes with a progressively lengthening PR interval. Second-degree heart block Type I is typically less severe than Type II and may not require immediate intervention.<br/><br/>Option L) First-degree heart block: First-degree heart block is a condition in which there is a delay in conduction between the atria and ventricles. On an ECG or rhythm strip, it is characterized by a prolonged PR interval. First-degree heart block is usually a benign condition and does not typically require treatment unless it causes symptoms or progresses to higher-degree blocks.<br/><br/>Option M) Normal sinus rhythm: Normal sinus rhythm is the normal electrical activity of the heart, originating from the sinus node. It is characterized by a regular rhythm, a heart rate between 60 and 100 beats per minute in adults, and a normal P wave, PR interval, QRS complex, and T wave on an ECG or rhythm strip. Normal sinus rhythm indicates a healthy functioning of the heart.

✓ Correct answer: A. Sodium nitroprusside

Sodium nitroprusside is a medication that is used to lower blood pressure in emergency situations. It acts as a vasodilator, meaning it relaxes and widens the blood vessels, leading to a decrease in blood pressure. However, this medication can have significant effects on the cardiovascular system and therefore requires meticulous hemodynamic monitoring.<br/><br/>Option B: Magnesium sulfate is a medication that is commonly used to treat conditions like eclampsia and preterm labor. While it can have side effects such as low blood pressure and slowed heart rate, meticulous hemodynamic monitoring is not typically required during its administration.<br/><br/>Option C: Sodium bicarbonate is a medication that is used to treat conditions such as metabolic acidosis. It can help restore the acid-base balance in the body. Although it may have some effects on blood pressure and heart rate, meticulous hemodynamic monitoring is not typically necessary during its administration.<br/><br/>Option D: Naloxone is a medication that is used to reverse the effects of opioids, particularly in cases of opioid overdose. While it can lead to changes in blood pressure and heart rate, meticulous hemodynamic monitoring is not typically required during its administration.<br/><br/>In summary, sodium nitroprusside is the medication that necessitates meticulous hemodynamic monitoring while being administered, as it can have significant effects on the cardiovascular system.

✓ Correct answer: C. Check for the return of spontaneous circulation (ROSC).

In this scenario, the patient is experiencing chest pain and is found to have multifocal premature ventricular contractions (PVCs) on the ECG monitor. The patient's condition is unstable, and a shock is delivered to treat the underlying arrhythmia.<br/><br/>After delivering the shock, the immediate next step is to check for the return of spontaneous circulation (ROSC). ROSC refers to the return of a sustained perfusing rhythm with palpable pulses and signs of adequate circulation. It indicates that the heart has restarted an effective rhythm, and blood flow has been restored to vital organs.<br/><br/>Option A (Administer amiodarone) is an appropriate intervention for certain types of ventricular arrhythmias, but it should be considered after ROSC has been achieved and the patient's rhythm has stabilized.<br/><br/>Option C (Prepare to administer epinephrine) is used during cardiac arrest resuscitation to support circulation, but it should be considered after the initial shock and evaluation for ROSC.<br/><br/>Option D (Assess the patient's level of consciousness) is essential to monitor the patient's neurological status, but it can be performed concurrently while checking for ROSC.<br/><br/>Remember, immediately after delivering a shock, the healthcare provider should check for the return of spontaneous circulation (ROSC) to determine if the patient's heart has responded to the defibrillation and if blood circulation has been restored.