Skip to content
Free NREMT practice questionsFree Paramedic practice questions · Cardiology & Resuscitation

10 free Paramedic practice questions: ACLS Pharmacology and Electrical Therapy

These are real questions from the same bank the app draws from. Each one is written to the NREMT Paramedic content specifications and kept inside the Paramedic scope of practice. Pick an answer and you get the full rationale, including why the other three options are wrong.

Work through all 10, then move on to the next topic. When you want the full picture, the free Paramedic diagnostic covers every topic in one sitting. No account needed for any of it.

Question 1 of 10

A 66-year-old patient is in ventricular fibrillation. A firm rectangular device is palpable under the skin below the left clavicle with a healed scar over it. Compressions are in progress and the pads have not yet been placed. What placement is most appropriate?

Show the answer and rationale

Correct answer · Place the pads at least 8 cm away from the device

An implanted pacemaker or defibrillator sits right where the standard anterior pad wants to go. A pad placed on top of the generator can block or scatter the current you are trying to deliver, and repeated shocks through the generator can damage it, so keep the pads at least 8 cm from its outline. Front to back placement is a clean way to get that distance. Never wait to see whether the implanted device will treat the rhythm itself, because a pulseless shockable rhythm needs the shock now.

Why the others are wrong

Place one pad directly over the device to shorten the path: Current that runs through the generator is current that does not run through the heart muscle, and the device can be damaged in the process. Distance is what protects both.

Place both pads on the right chest to avoid the device: Both pads on one side of the chest does not put the heart in the current path. The pads have to straddle the heart to defibrillate it.

Withhold the shock and let the implanted device deliver it: The patient is in ventricular fibrillation with an implanted device that has not converted it, which tells you the device is not going to solve this one. External defibrillation proceeds.

Question 2 of 10

A 5-year-old child weighing 18 kg is in ventricular fibrillation. Compressions are in progress, pediatric pads are in place, and the monitor is in manual mode. What energy should the first shock deliver?

Show the answer and rationale

Correct answer · 36 joules, using 2 joules per kilogram

Pediatric manual defibrillation is dosed by weight. The first shock is 2 joules per kilogram, which is 36 joules for an 18 kilogram child. The second shock doubles to 4 joules per kilogram, and the shocks after that are at least 4 joules per kilogram, escalating toward 10 joules per kilogram or the adult maximum, whichever comes first. Selecting that energy yourself is the part that separates manual defibrillation from letting an automated device analyze and advise.

Why the others are wrong

72 joules, using 4 joules per kilogram: Four joules per kilogram is the second shock and the floor for the shocks after it. Starting there skips the first rung of the ladder.

The adult biphasic setting of 200 joules: The adult biphasic setting overshoots badly in an 18 kilogram child. Pediatric energy is calculated from weight until the calculated number reaches the adult maximum.

18 joules, using 1 joule per kilogram: One joule per kilogram sits in the pediatric cardioversion range rather than the defibrillation range. Half the needed energy is unlikely to terminate ventricular fibrillation.

Question 3 of 10

A 22-year-old patient has been pulled from a lake onto the shore after an estimated 6 minutes underwater. The patient is unresponsive, apneic, and has no palpable carotid pulse. There is no report of diving and no evidence of injury. Two paramedics are on scene, and a BVM device with oxygen, suction, and a cardiac monitor are immediately available. What is the most appropriate approach to resuscitation?

Show the answer and rationale

Correct answer · Compressions and ventilations at a ratio of 30 to 2

Drowning produces a hypoxic arrest, not a cardiac one. Laryngospasm and aspiration cause progressive hypoxemia, the myocardium is starved of oxygen, and the heart stops as a consequence. That mechanism is why drowning is an explicit exception to compression-only resuscitation: the blood circulating after 6 minutes underwater has no oxygen left in it, so compressions alone circulate nothing useful. Resuscitation is performed with ventilations from the start, at 30 compressions to 2 ventilations in an adult, and with two paramedics on scene and a BVM with oxygen at hand, there is nothing preventing it. The umbrella rule to carry forward: any arrest whose cause was a failure to oxygenate gets ventilations from the first cycle.

Why the others are wrong

Abdominal thrusts to clear water before ventilating: Abdominal thrusts are the intervention for a foreign body airway obstruction in a responsive choking adult. Applying them here rests on a misconception, that the lungs are full of water that must be expelled first. The volume actually aspirated in drowning is small and absorbs rapidly into the circulation, so there is nothing to expel and no obstruction to relieve. Thrusts delay compressions and ventilations and sharply raise the risk of regurgitation in a patient already prone to vomiting.

Continuous compressions without delivered ventilations: Compression-only resuscitation is correct for an adult with a sudden witnessed collapse from a primary cardiac cause, where the blood is still oxygenated for the first several minutes and uninterrupted compressions circulate that reserve. Drowning is the named exception, because hypoxia is what caused the arrest and that oxygen reserve is already gone after 6 minutes underwater. Compressions without ventilations here move desaturated blood around a body that needs oxygen added, which is why the 30 to 2 ratio is used from the first cycle.

Suctioning of the airway until no further water returns: Suctioning is essential when something is physically blocking ventilation: vomit, secretions, or blood, and suction is kept at hand on every submersion call for exactly that reason, because these patients vomit frequently. Suctioning to an endpoint of no further water, though, chases something that is not there, and every second spent on it is a second without compressions and without oxygen. Suction when there is an obstruction in the way, and ventilate otherwise.

Question 4 of 10

A 71-year-old patient reports the sudden onset of severe, constant abdominal pain that radiates into the back and began 1 hour ago. The patient has a history of hypertension and has smoked for 40 years. The abdomen is tender, and a pulsatile mass is palpated to the left of the midline above the umbilicus. The skin is pale, cool, and diaphoretic. The vital signs are BP 88/56, P 124, and R 24, with SpO₂ 95% on room air. What condition should the paramedic most strongly suspect as the cause of this emergency?

Show the answer and rationale

Correct answer · Abdominal aortic aneurysm

A pulsatile abdominal mass is the finding that belongs to one condition and no other, and it becomes decisive when it appears alongside sudden, severe, steady abdominal pain radiating to the back in a 71-year-old with hypertension and a 40-year smoking history: the exact risk profile that weakens an aortic wall. The hypotension, the rate of 124, and the pale, cool, diaphoretic skin say blood is already being lost into the retroperitoneum, so this is a leaking aneurysm rather than an incidental one. Field management is minimal palpation of the mass, large-bore intravenous access, shock management, and immediate transport to a facility with vascular surgical capability. Note the direction of the logic: a pulsatile mass rules the diagnosis in, but its absence would not rule it out, since it is hard to appreciate in a larger patient or a smaller aneurysm.

Why the others are wrong

Perforated peptic ulcer: A perforated peptic ulcer produces sudden, severe upper abdominal pain with a rigid, board-like abdomen, typically in a patient with an ulcer history or heavy anti-inflammatory use, and it can certainly produce shock, so the onset and the hemodynamics overlap. What it cannot produce is a pulsatile mass, and it does not carry pain radiating straight through to the back in a hypertensive elderly smoker. The mass is the finding only an aneurysm makes, which is why it settles the question.

Acute pancreatitis: epigastric pain boring into the back, usually with nausea and vomiting, in a patient with alcohol use or gallstones: the back radiation is the genuine overlap with the key. Pancreatitis builds over hours rather than arriving fully formed in an hour, does not produce a pulsatile mass, and does not fit a risk profile built on age, hypertension, and four decades of smoking. Same location and same radiation, but only one of the two can be felt beating under the hand.

Renal colic: sudden, severe flank pain radiating to the groin in a patient who cannot get comfortable, and it is the classic mimic that gets aneurysms missed, since both are abrupt, severe, and involve the flank and back. The separator is hemodynamic: a stone hurts enormously but does not drop a pressure to 88/56 with pale, cool, diaphoretic skin. Pain plus shock plus a pulsatile mass means bleeding, and a stone does not bleed into the retroperitoneum.

Question 5 of 10

A 6-year-old patient weighing 22 kilograms is unresponsive, apneic, and pulseless. Chest compressions have been started and positive pressure ventilations are being delivered. The monitor shows a coarse disorganized waveform with no identifiable QRS complexes, and the defibrillator pads are in place. Which initial defibrillation energy is most appropriate?

Show the answer and rationale

Correct answer · 2 joules per kilogram

A coarse disorganized waveform with no identifiable QRS complexes is ventricular fibrillation, and fibrillation is shockable at any age. Pediatric defibrillation is dosed by weight rather than by a fixed setting, because myocardial mass and transthoracic impedance vary enormously across childhood. The first shock is 2 joules per kilogram, which for this 22-kilogram patient is about 44 joules. If fibrillation persists, subsequent shocks go to 4 joules per kilogram and may escalate further, not exceeding 10 joules per kilogram or the adult dose. Starting at the lowest effective energy limits myocardial injury while still terminating the rhythm in most children, and compressions resume immediately after the shock either way.

Why the others are wrong

10 joules per kilogram: Ten joules per kilogram is the ceiling of the pediatric escalation, not the entry point, and it is where later shocks may land if fibrillation keeps recurring. Opening at the maximum delivers energy the myocardium does not need to convert on a first attempt. That adds myocardial injury to a heart that still has to work after the rhythm is fixed, while the key starts at the dose that terminates most pediatric fibrillation on the first try.

4 joules per kilogram: Four joules per kilogram is a correct dose, just not for this shock; it applies to the second and every subsequent shock. It is also the number most people remember, since it covers every shock after the first, which makes it the easiest sequencing error on the exam. The question asks specifically for the initial energy, and the initial energy is half of this.

The manufacturer's adult setting: what an automated external defibrillator (AED) without a pediatric attenuator delivers, and using it is far better than not shocking a child in ventricular fibrillation at all. That is a fallback for missing equipment rather than a plan. This crew has a manual defibrillator with pads already in place and a documented weight of 22 kilograms, so weight-based dosing is available and clearly preferred.

Question 6 of 10

A 68-year-old patient reports palpitations and lightheadedness. The patient is drowsy and answers questions slowly, and the skin is pale, cool, and diaphoretic. The cardiac monitor shows a regular wide-complex rhythm at 168 with no identifiable P waves. The vital signs are BP 78/46, P 168, R 20, SpO₂ 94% on room air. An intravenous line is in place, and the paramedic prepares for synchronized cardioversion. Which initial energy setting is most appropriate?

Show the answer and rationale

Correct answer · 100 joules

Two questions get answered in sequence here. First, is the patient unstable because of the rate, and the answer is yes, since the drowsiness, the blood pressure of 78/46, and the pale, cool, diaphoretic skin all track with a rate of 168, which makes electricity the treatment rather than a drug. Second, how much energy, and that is decided by the shape and regularity of the rhythm, because those determine how hard it is to depolarize the whole myocardium at once. The full rule sorts into three buckets: regular narrow starts at 50 to 100 joules, regular wide starts at 100 joules, and irregular narrow such as atrial fibrillation needs 120 to 200 joules. This rhythm is regular, wide, and has no identifiable P waves, so 100 joules is the matched starting point, escalated stepwise if the first shock does not convert it.

Why the others are wrong

50 joules: the correct starting energy for a regular narrow-complex tachycardia, the stable-looking supraventricular tachycardia or atrial flutter that converts easily because a single reentrant circuit has to be interrupted. The rhythm described here is wide, which means more myocardium has to be depolarized simultaneously, so 50 joules is likely to fail. A failed shock is not free in a patient who is already drowsy and hypotensive, because it costs time and buys another painful discharge.

360 joules: a maximum defibrillation energy on some monophasic devices, delivered to a pulseless patient in ventricular fibrillation where there is no rhythm left to protect. This patient has a pulse and a blood pressure, so the shock is synchronized and started at the recommended low end, then escalated only if needed. Starting at the top delivers far more current than the rhythm requires and adds myocardial injury for no gain.

200 joules: the top of the recommended range for an irregular narrow-complex rhythm, most often atrial fibrillation, where many simultaneous atrial wavefronts require more energy than a single circuit does. This question describes a regular rhythm, not an irregular one, so it falls in the wide-regular bucket that starts at 100. The energy is matched to the rhythm and then escalated, which is why 100 is the answer and 200 is where escalation might end up.

Question 7 of 10

A 24-year-old patient is lethargic 90 minutes after swallowing a large number of amitriptyline tablets. The pupils are dilated, the skin is warm and dry, and the mouth is dry. The vital signs are BP 96/58, P 124, R 16, SpO₂ 97% on room air. The 12-lead ECG shows a sinus tachycardia with a QRS duration of 0.16 seconds and a tall terminal R wave in lead aVR. An intravenous line is in place. Which medication should the paramedic administer first?

Show the answer and rationale

Correct answer · Sodium bicarbonate 1 mEq/kg intravenously

Tricyclic antidepressants block the fast sodium channels that drive ventricular depolarization, and that single mechanism explains both ECG findings: the QRS widens past 0.10 seconds and a tall terminal R wave appears in lead aVR. Those two together are the fingerprint of sodium channel blockade, and they are the warning that the same blockade is about to produce ventricular dysrhythmias, seizures, and hypotension as the level climbs. Sodium bicarbonate attacks the blockade from two directions at once: the sodium load raises the gradient across the channel so more current gets through, and alkalinizing the blood shifts more of the drug into its protein-bound form so less is free to bind. Narrowing of the QRS after administration is the bedside confirmation that it is working. The anticholinergic picture of dilated pupils, dry skin, dry mouth, and tachycardia supports the ingestion but is not the thing being treated.

Why the others are wrong

Lidocaine 1 mg/kg intravenously: Lidocaine is a ventricular antidysrhythmic, and it is tempting here for the obvious reason that the complexes are wide. Look at what lidocaine is, though: it is itself a sodium channel blocker, so giving it adds to the exact blockade producing the widening. This is the one class specifically avoided in tricyclic toxicity, and it is the difference between treating the mechanism and doubling it.

Amiodarone 150 mg intravenously over 10 minutes: Amiodarone is for stable wide-complex tachycardia, a fast ventricular rhythm you are trying to slow and organize. The rhythm here is a sinus tachycardia whose QRS is widened by drug toxicity, not a tachydysrhythmia in need of suppression. Amiodarone also has sodium channel blocking activity of its own and prolongs the QT interval, so it stacks a second conduction problem onto the one the poison already created.

Calcium chloride 1 g intravenously: Calcium chloride is the antidote aimed at calcium channels, which makes it the drug for calcium channel blocker toxicity, refractory beta-blocker toxicity, and hyperkalemia. Amitriptyline does not block calcium channels, so calcium does not reach the receptor causing this presentation. The terminal R wave in aVR with a QRS of 0.16 names the channel involved, and sodium bicarbonate is the agent aimed at that channel.

Question 8 of 10

A 74-year-old patient reports a racing heartbeat that began 1 hour ago. The patient is confused and answers questions slowly, and the skin is pale, cool, and diaphoretic. Crackles are heard at both lung bases. The vital signs are BP 78/50, P 168, R 24, SpO₂ 93% on room air. The cardiac monitor shows an irregularly irregular narrow-complex rhythm at 168 with no discernible P waves. An intravenous line is in place and the patient has received sedation. Which action is most appropriate?

Show the answer and rationale

Correct answer · Synchronized cardioversion at 120 joules

Two separate decisions are being made, and both are settled by what is on the monitor next to how the patient looks. First, mode. The patient is unstable, with confusion, a blood pressure of 78/50, and crackles at both bases, all attributable to a rate of 168, so electrical therapy replaces drug therapy. Because a pulse is present the shock must be synchronized to the QRS complex, so it cannot land on a T wave during repolarization and convert a perfusing rhythm into ventricular fibrillation. Second, energy, which follows the shape of the rhythm. An irregularly irregular narrow-complex rhythm with no discernible P waves is atrial fibrillation, and the recommended initial biphasic energy for narrow and irregular is 120 to 200 joules, higher than the 50 to 100 joules used for narrow and regular because fibrillating atria present many simultaneous wavefronts rather than one circuit to interrupt.

Why the others are wrong

Synchronized cardioversion at 50 joules: gets the mode right and the energy wrong. 50 joules is the correct starting point for a regular narrow-complex tachycardia such as supraventricular tachycardia or atrial flutter, where a single reentrant circuit is being interrupted and low energy suffices. This rhythm is irregularly irregular with no P waves, which is atrial fibrillation, and it needs 120 to 200 joules. An underpowered shock is likely to fail, and a failed shock costs time and one more painful discharge in a patient who is already confused and hypotensive.

Unsynchronized shock at 120 joules: An unsynchronized shock at 120 joules has the right energy and the wrong mode, which is the more dangerous of the two errors. Unsynchronized means the defibrillator discharges the instant the button is pressed, with no regard for where the heart is in its cycle, and current landing on a T wave during repolarization can throw a perfusing rhythm into ventricular fibrillation. Unsynchronized shocks belong to pulseless rhythms; this patient has a pulse, so synchronization is the safeguard.

Unsynchronized shock at 200 joules: An unsynchronized shock at 200 joules is wrong on both counts. It abandons synchronization in a patient with a pulse, carrying the same risk of inducing fibrillation, and 200 joules is the ceiling of the range for an irregular narrow rhythm rather than its starting point. Energy is matched to the rhythm and escalated stepwise, so 120 joules is where this begins and 200 is where escalation might end.

Question 9 of 10

A 58-year-old patient is in cardiac arrest, and no bystander cardiopulmonary resuscitation was performed before EMS arrival. High-quality chest compressions have been in progress for 22 minutes, an endotracheal tube is in place, the rhythm has been asystole throughout, and epinephrine has been given every 4 minutes. There is no history of kidney failure and no suspected overdose, and the blood glucose level is 104 mg/dL. Which action is most appropriate?

Show the answer and rationale

Correct answer · Continue compressions and epinephrine dosing

A long down time creates a strong pull toward doing something extra, and the something usually proposed is a buffer or an electrolyte. The question is built to close off every reason to reach for one: no kidney failure, no suspected overdose, and a normal glucose. What remains is an arrest being treated correctly, so the answer is to keep doing it. There is also a mechanism behind why routine buffering fails rather than merely being unhelpful, and it is worth knowing: bicarbonate is converted to carbon dioxide, which has to be carried away by a pulmonary circulation that during compressions is a fraction of normal, and the carbon dioxide that cannot be exhaled diffuses back into cells and worsens the intracellular acidosis it was given to correct. Uninterrupted compressions, controlled ventilation, and epinephrine on schedule remain the treatment while the resuscitation is continued or termination criteria are considered.

Why the others are wrong

Administer sodium bicarbonate 1 mEq/kg: Sodium bicarbonate has genuine, specific indications in arrest: sodium channel blocking overdose such as a tricyclic, and known or suspected hyperkalemia. Both are named and excluded by this question, which states there is no history of kidney failure and no suspected overdose. Given routinely for presumed acidosis it has not improved survival or neurologic outcome, and by the carbon dioxide mechanism above it can deepen the very acidosis it targets, so it displaces effort from compressions without returning anything.

Administer calcium chloride 1 g: Calcium chloride is indicated for hyperkalemia, calcium channel blocker toxicity, and magnesium toxicity, which are exactly the causes a paramedic would suspect from a dialysis history or a pill bottle. This question removes both routes to that suspicion. Routine calcium in undifferentiated arrest has not improved outcome and may worsen reperfusion injury, so it is the right drug held for a cause this patient does not have.

Increase the ventilation rate to correct acidosis: Increasing the ventilation rate to correct acidosis is the most physiologically appealing wrong answer, because the acidosis is real and blowing off carbon dioxide is how the body normally compensates. The problem is the tradeoff: hyperventilation raises intrathoracic pressure, reduces venous return, and lowers coronary perfusion pressure, so it trades circulation for a pH number. The acidosis of cardiac arrest is a flow problem, and the fix for a flow problem is better flow, which is what continued high-quality compressions provide.

Question 10 of 10

A 61-year-old patient being monitored during transport for chest discomfort suddenly slumps forward and becomes unresponsive. The patient is apneic and has no palpable carotid pulse. Defibrillation pads are already attached, and the monitor shows a chaotic waveform with no organized complexes. Which action is most appropriate?

Show the answer and rationale

Correct answer · Defibrillate as soon as the device is charged

The single strongest predictor of survival from ventricular fibrillation is the interval between the onset of the rhythm and the first shock, and in this scenario that interval can be nearly zero. The arrest was witnessed on the monitor during transport and the defibrillation pads are already attached, so the myocardium is still oxygenated, the fibrillation is still coarse, and the probability that a shock terminates it is at its absolute peak right now. Every minute that passes drops that probability measurably. Compressions are performed while the device charges so perfusion is never idle, but they are a companion to the shock rather than a reason to postpone it. Charge, clear, shock, and resume compressions immediately afterward.

Why the others are wrong

Confirm the rhythm in a second lead before shocking: Confirming a rhythm in a second lead is real discipline, and it is the correct habit for asystole, where a flat line can be produced by a disconnected lead, poor contact, or fine fibrillation viewed at the wrong angle, and where calling it wrong means withholding a shock that was indicated. That reasoning does not transfer here, because a chaotic waveform with no organized complexes in a pulseless patient is unambiguous ventricular fibrillation. Extra confirmation buys no new information and spends the seconds in which defibrillation is most likely to work.

Perform 2 minutes of compressions before shocking: Performing 2 minutes of compressions before shocking reflects the older CPR-first approach for an unwitnessed arrest with a prolonged down time, where perfusing a depleted myocardium first may make it more receptive to a shock. This is the opposite situation in every respect: the arrest was witnessed on the monitor moments ago, so the myocardium has not had time to deplete. Delaying a shock that is available now to perform compressions that are meant to substitute for one gives away the advantage the monitoring provided.

Administer epinephrine 1 mg before shocking: Administering epinephrine before shocking puts a supporting drug ahead of the definitive treatment. Epinephrine belongs in this resuscitation, given after the first shock and repeated every 3 to 5 minutes, and it improves coronary perfusion pressure during compressions. What it does not do is terminate ventricular fibrillation, because no drug does. In a patient found in a shockable rhythm with pads already on, nothing goes ahead of the shock.

Find out which Paramedic topics are costing you points

Ten questions on one topic tell you about that topic. The free diagnostic covers every Paramedic topic and breaks your results down by topic, so you know what to drill next. No card, no signup to try it.

Take the free Paramedic diagnostic

More free Paramedic practice questions by topic