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Free NREMT practice questionsFree AEMT practice questions · Airway, Respiration & Ventilation

10 free AEMT practice questions: Ventilation and Oxygenation Support

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

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Question 1 of 10

A supraglottic airway has been placed and confirmed in a 64-year-old patient in cardiac arrest. Compressions have been running at 30 to 2. How do compressions and ventilations run from this point?

Show the answer and rationale

Correct answer · Continuous compressions with one breath every 6 seconds

With a supraglottic airway in place and confirmed, compressions no longer stop for breaths. Before the airway, you run 30 compressions to 2 breaths, and the compressor pauses for the breaths. The supraglottic airway seals the airway, so the breaths can go in while compressions keep going. Compressions run nonstop at 100 to 120 a minute. Give one breath every 6 seconds for an adult. For an infant or a child, give one breath every 2 to 3 seconds. Every pause in compressions stops blood flow, and the airway lets you skip those pauses. Keep counting your breaths. With nobody pausing for you, it is easy to start bagging too fast.

Why the others are wrong

Continuous compressions with one breath every 3 seconds: One breath every 3 seconds is 20 breaths a minute. That rate is for an infant or a child. In an adult, breathing that fast raises the pressure inside the chest. Higher chest pressure cuts down the blood your compressions send back to the heart.

Continuous compressions with one breath every 10 seconds: One breath every 10 seconds is only 6 breaths a minute. Six breaths a minute is too slow to clear the carbon dioxide your compressions bring to the lungs. This patient is in cardiac arrest and is not breathing, so nothing makes up the difference.

Cycles of 30 compressions to 2 breaths, continued as before: Cycles of 30 to 2 are right until an advanced airway goes in. This supraglottic airway is in and confirmed. Staying at 30 to 2 keeps every pause for breaths, and every pause stops blood flow.

Question 2 of 10

A 55-year-old patient is in respiratory arrest with a pulse and a partner is ventilating with a BVM, squeezing about every 2 seconds. The chest rises fully with each breath and there is no gastric distention. Over the next two minutes the blood pressure falls from 118/70 mmHg to 84/50 mmHg and the pulse climbs from 96 to 124. What best explains the falling blood pressure?

Show the answer and rationale

Correct answer · Higher pressure inside the chest is cutting venous return

This patient is being ventilated too fast. The high pressure inside the chest is cutting the venous return, the blood coming back to the heart. The partner is squeezing about every 2 seconds. Every breath from the bag raises the pressure inside the chest. Between breaths, the pressure has to fall back down so blood can refill the heart. A new breath every 2 seconds does not give the pressure time to fall. Less blood comes back to the heart, so the heart pumps out less blood. The blood pressure dropped from 118/70 to 84/50, and the pulse climbed from 96 to 124 to make up for it. Ventilating too fast is the most common harmful mistake in prehospital airway care. Fast bagging does the most harm in a patient with low blood pressure and in a patient in cardiac arrest. In cardiac arrest, less blood coming back to the heart works against your compressions. An adult in respiratory arrest with a pulse gets one breath every 6 seconds, which is 10 breaths per minute. Slow down, and use a timer or the rate display on your capnography to hold that rate.

Why the others are wrong

Each breath is delivering a lower oxygen concentration: A bag without a reservoir does give much less oxygen. The oxygen concentration from the bag depends on the flow and the reservoir, not on how often you squeeze. A change in oxygen concentration also would not drop a blood pressure in two minutes.

The fast rate is raising the carbon dioxide and dropping the pressure: Carbon dioxide does change with your ventilation rate, and carbon dioxide does affect the blood vessels. Fast ventilation blows off more carbon dioxide, so the level goes down, not up. A falling carbon dioxide level is not what dropped this pressure.

The shortened breaths are making the patient hypoxic: Fast, shallow breaths can leave a patient hypoxic, and you see that in patients who are breathing on their own. This patient's chest rises fully with each breath, so each breath is delivering a full volume. Hypoxia this early would show up as a falling saturation, not a falling blood pressure.

Question 3 of 10

A single AEMT is ventilating a 48-year-old patient who is apneic with a BVM. The chest barely moves with each squeeze, air leaks audibly with every breath, and the upper abdomen is becoming visibly distended. An oropharyngeal airway is already in place and the reservoir is inflated on 15 liters per minute. What should the AEMT do first?

Show the answer and rationale

Correct answer · Reposition the head and recheck the mask seal

Reposition the head and recheck the mask seal. The chest barely moves, air leaks out with every breath, and the upper abdomen is getting distended. The air is leaking out around the mask and going down into the stomach instead of into the lungs. Head position and the mask seal fix both problems, and both sit at the top of the recheck list. Work the list in order. Check head position first, then the mask seal, then look for anything that needs suction. Next, put two providers on the mask. Only then move to a supraglottic airway, if the patient meets the indications. Gastric distention gets worse while you work. A full stomach pushes the diaphragm up and makes the chest harder to ventilate. A chest that is hard to ventilate gets squeezed harder, and harder squeezes put more air in the stomach. One AEMT trying to seal the mask, hold the jaw, and squeeze the bag at the same time leads to exactly this leak and distention. A second set of hands on the mask comes right after head position and the seal.

Why the others are wrong

Squeeze the bag with more force on each breath: More force does move more air when the resistance is in the lungs. Force is also what pushes air into the stomach in the first place. With a leaking seal and a partly closed airway, the extra pressure takes the easier path, out the mask and into the stomach.

Place a supraglottic airway device now: A supraglottic airway does solve a mask seal problem, and this patient may end up with one. The supraglottic airway comes at the end of the recheck list, not the start. Head position and the mask seal cost nothing, take seconds, and fix this problem far more often than the device does.

Switch to a smaller mask and try the same breaths: A mask that does not fit the face is a real cause of a leak. A smaller mask on an adult face usually leaks more, not less. Changing equipment before you fix the head position also skips the step that fixes most of these leaks.

Question 4 of 10

An AEMT is ventilating a 60-year-old patient who has a supraglottic airway in place after a drug overdose, and the patient has a strong pulse at 88 with a blood pressure of 122/74 mmHg. Over ten minutes the end-tidal carbon dioxide has drifted from 38 mmHg down to 23 mmHg. The waveform is still a clean rectangle that returns to the baseline, chest rise is good, and the partner on the bag is squeezing about every 3 seconds. What should the AEMT do?

Show the answer and rationale

Correct answer · Slow the rate to 10 breaths per minute

This patient is being ventilated too fast. Your partner is squeezing about every 3 seconds. That is 20 breaths a minute in an adult who should be getting 10. Read the capnogram in two parts. The shape tells you about the airway and the lungs. A clean rectangle that returns to the baseline says both are fine. The height tells you about breathing and blood flow. The number fell from 38 to 23 mmHg while the shape held. A falling number with a normal shape means carbon dioxide is leaving faster than the body is making it. Ventilating too fast is the most common cause. Slow to 10 breaths a minute, which is one breath every 6 seconds. The number should climb back toward the normal range of 35 to 45 mmHg. Poor blood flow also lowers the number, so check and fix the rate first. Once the rate is right, a number that stays low points to how much blood is reaching the lungs.

Why the others are wrong

Give an isotonic crystalloid bolus for poor perfusion: This patient has a strong pulse at 88 and a blood pressure of 122/74, so perfusion has not changed. The fast rate explains the falling number without any fluid. Less blood reaching the lungs can lower the number too, but nothing here points to that.

Remove the device and ventilate with a BVM: C does not work because the tracing is still a clean rectangle that returns to the baseline, and chest rise is good. The device is working. A device comes out when the waveform never shows up at confirmation or disappears later.

Increase the oxygen flow running to the bag: Oxygen flow sets the oxygen concentration in the bag and has no effect on the carbon dioxide number. That number depends on how much air you move and how much blood reaches the lungs.

Question 5 of 10

An AEMT is treating a 68-year-old patient with a history of chronic obstructive pulmonary disease (COPD) who has difficulty breathing. The patient is on oxygen by NRB at 15 liters per minute, and the SpO₂ has risen from 82% to 86%. The patient's usual saturation is not known. A crew member states that the oxygen should be turned down to protect the patient's drive to breathe. Which action does the AEMT take?

Show the answer and rationale

Correct answer · Continue oxygen and titrate toward an SpO₂ of 88% to 92%

This patient is hypoxic. An SpO₂ of 86% on a nonrebreather means this patient is still short on oxygen. You never withhold or reduce oxygen in a hypoxic patient, whatever the medical history is. A patient with COPD gets oxygen titrated toward that patient's own normal saturation. This patient's normal is not known, so you aim for 88% to 92%. Titrating means adjusting the flow to reach that range as the saturation comes up. Turning the oxygen down to protect the drive to breathe is not titrating, because this patient is still hypoxic.

Why the others are wrong

Reduce the oxygen flow to protect the drive to breathe: Turning the oxygen down is what the crew member suggested, and it is the one thing you do not do. At 86%, this patient is hypoxic. You never withhold or reduce oxygen in a hypoxic patient. Cutting the flow treats a theory instead of the number in front of you.

Switch the patient to a nasal cannula at 2 liters per minute: Low flow for every COPD patient is a common blanket rule. Titration follows the saturation, not the diagnosis. Dropping a hypoxic patient to a nasal cannula at 2 liters per minute is still cutting the oxygen, just with a different device.

Continue oxygen until the SpO₂ reaches 100%: Running oxygen until the SpO₂ reads 100% treats more oxygen as always better. When the baseline is unknown, the target for a COPD patient is 88% to 92%. Pushing past that range means you never titrated at all.

Question 6 of 10

First responders placed an NRB at 15 L per minute on a 62-year-old patient about ten minutes ago. The AEMT arrives to find the patient unresponsive, breathing 6 times a minute, with chest movement that is barely visible. The vital signs are BP 128/76, P 96, R 6, and SpO₂ 96% on the mask. Which statement describes what that mask is doing for this patient?

Show the answer and rationale

Correct answer · It raises the oxygen in each breath, but it does not move air for the patient

This patient is getting oxygen but is not moving enough air. Oxygenation and ventilation are two different jobs. A patient can fail one while the other looks fine. The NRB is doing the oxygen job. The mask raises the oxygen in whatever air this patient pulls in, and that is why the SpO₂ reads 96%. The NRB cannot do the ventilation job. This patient is unresponsive and breathing 6 times a minute. The chest movement is barely visible. Breathing that slow and shallow does not move enough air to clear carbon dioxide. Turning the flow up does not fix the problem, because a mask has no way to push a breath in. The bag-valve mask is the only device you carry that moves air for this patient.

Why the others are wrong

It oxygenates and ventilates, since oxygen at 15 L per minute pushes air into the chest: Fifteen liters a minute is the highest flow you run through a mask. A flow that high can seem like it is pushing air. The flow only fills the mask and the reservoir bag. The oxygen never becomes a breath, because the mask has no seal and nothing squeezing air into the chest.

It is clearing carbon dioxide, because the valve vents each exhalation out of the mask: The valve does let each exhalation leave the mask instead of going back into the reservoir bag. Getting carbon dioxide out of the mask is different from getting it out of the patient. Carbon dioxide only leaves the patient when enough air moves in and out of the lungs.

It is all this patient needs while the saturation stays at or above 94 percent: A saturation of 96% is a reassuring number, and it tells you the oxygen side is covered for now. The pulse oximeter only reports one of the two jobs. This patient is breathing 6 times a minute with almost no chest movement, and that is the ventilation job failing.

Question 7 of 10

A trauma patient in shock has significant hypoxia and is breathing adequately on their own. The AEMT applies an NRB at 15 L/min. Five minutes later the oxygen saturation remains at 85%, and the respirations have become shallow. What is the most appropriate next action?

Show the answer and rationale

Correct answer · Assist ventilations with a BVM, synchronized with the patient's breathing

This patient is no longer breathing adequately. The respirations have become shallow, and the oxygen saturation is still 85% after five minutes on a nonrebreather at 15 L/min. Shallow breaths move only a small amount of air in and out of the alveoli. The nonrebreather fills the air at the face with oxygen, and the patient still has to pull that air down into the lungs. Shallow breaths do not pull enough of it down. Assist ventilations with a BVM, and time each squeeze with the patient's own breath. Each assisted breath pushes more air into the alveoli, so more oxygen can reach the blood.

Why the others are wrong

Continue the NRB unchanged and reassess again in five minutes: Five minutes at 15 L/min have already passed, the saturation is still 85%, and the breaths have become shallow. Another five minutes of the same thing only delays the ventilations this patient needs.

Switch to a nasal cannula, which delivers a lower oxygen concentration: A cannula gives less oxygen than the nonrebreather that already left this patient at 85%. It also does nothing to move more air through shallow breaths.

Withhold further intervention, since the patient is still breathing on their own: Breathing on their own is not the same as breathing adequately. This patient is still breathing, but the breaths are shallow, and shallow breathing calls for a BVM.

Question 8 of 10

An AEMT is considering CPAP for a patient in respiratory distress. The patient is actively vomiting. Which of the following is true regarding CPAP in this situation?

Show the answer and rationale

Correct answer · CPAP is contraindicated because of the aspiration risk from active vomiting

CPAP is contraindicated because this patient is actively vomiting. A CPAP mask works by sealing over the nose and mouth. The mask pushes in constant pressure that opens up the alveoli and makes breathing easier. The same seal traps vomit in the mouth and throat with no way out. With the pressure behind it, the patient can aspirate the vomit down into the lungs. Position the patient and suction to clear and protect the airway first. Hold off on CPAP until the vomiting has stopped and the airway is secure.

Why the others are wrong

CPAP should be applied immediately to improve oxygenation before airway management: CPAP does improve oxygenation fast in flash pulmonary edema or a severe COPD exacerbation. This patient is vomiting right now. Sealing a mask over that airway pushes vomit into the lungs. Protecting the airway comes before any treatment that needs a sealed mask.

CPAP is appropriate as long as the mask is held slightly away from the face: Holding the mask a little off the face sounds like a way to get oxygen in without sealing over the vomit. CPAP only works with a tight seal. Without the seal there is no pressure and no benefit, and the patient is still vomiting with the same aspiration risk.

CPAP is contraindicated only if the patient is also hypotensive: Hypotension is a real contraindication for CPAP on its own. Positive pressure lowers preload, the blood coming back to the heart, and can make shock worse. This question gives you no blood pressure at all. Active vomiting is enough by itself to rule out CPAP.

Question 9 of 10

An AEMT administers nebulized albuterol to a wheezing asthma patient. After the treatment, the wheezing is louder and more audible than before, and the patient reports easier breathing with an improved capnography waveform. What does this change most likely mean?

Show the answer and rationale

Correct answer · The patient is moving more air than before, consistent with improvement

The louder wheeze means this patient is moving more air, and the albuterol is working. After the treatment, the wheeze got louder, the patient says breathing is easier, and the capnography waveform improved. Wheezing is the sound of air rushing through narrowed bronchioles. When the airways close almost all the way, so little air moves that you hear almost nothing. This is called a silent chest. Albuterol relaxes the muscle around the bronchioles. More air now pushes through those airways, and more air makes a louder sound. Continue the current plan and keep reassessing. Do not escalate care or hold back more nebulized doses because of the louder wheeze.

Why the others are wrong

The patient is deteriorating and bronchospasm is worsening: Worsening bronchospasm moves less air, not more. The wheeze gets quieter or goes away as the airways close. This patient says breathing is easier, and the capnography waveform got better.

The louder wheeze indicates the treatment failed and a repeat dose is contraindicated: A louder wheeze can mean the treatment failed when the patient is also getting worse or the capnography is flattening. Here the patient is breathing easier and the waveform is improving. Calling this a failure ignores both of those findings and would hold back a repeat dose the patient may need.

The change is unrelated to the treatment and should be disregarded: The wheeze changed right after the albuterol. The change matches the patient's report and the capnography. A change that lines up with the treatment is a treatment effect to track, not noise to ignore.

Question 10 of 10

An AEMT applies CPAP to a patient in cardiogenic pulmonary edema. Two minutes later, the patient's blood pressure has dropped from 158/92 mmHg to 96/60 mmHg, and the patient appears more lethargic. What should the AEMT do?

Show the answer and rationale

Correct answer · Reassess perfusion, and remove CPAP if hypotension or mental status decline persist

The blood pressure dropped from 158/92 to 96/60 after the CPAP went on, and the patient is more lethargic. The CPAP is the likely cause. CPAP raises the pressure inside the chest. Higher pressure in the chest cuts down how much blood comes back to the right side of the heart. Less blood coming back means less blood pumped out, and less blood flow to the brain. That is why the blood pressure fell and the patient got more lethargic. The higher the CPAP pressure, the bigger this effect gets. Reassess perfusion and mental status after every CPAP change. If the low blood pressure or the lethargy does not get better, turn the CPAP down or take it off.

Why the others are wrong

Increase the CPAP pressure setting to further reduce the work of breathing: The CPAP already on is the likely reason the pressure fell to 96/60, because it cuts down the blood coming back to the heart. Turning it up pushes the blood pressure and the mental status down even further.

Continue CPAP unchanged, since a pressure drop is an expected and desirable response: A drop to 96/60 with new lethargy is not what CPAP is supposed to do. The drop is a complication from less blood returning to the heart. You have to catch it and correct it, not leave the CPAP unchanged as if the drop were normal.

Immediately give a rapid isotonic fluid bolus without reassessing first: Giving a bolus before you reassess skips checking whether the CPAP is the cause, and taking the CPAP off may fix the drop by itself. A rapid bolus can also make the pulmonary edema worse in this cardiogenic patient.

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