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NREMT AEMT study materials
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NREMT AEMT practice questions

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Question 1Airway, Respiration & Ventilation

Which structure folds over the opening of the larynx during swallowing to help prevent aspiration?

  1. The uvula
  2. The vallecula
  3. The cricoid cartilage
  4. The epiglottis Correct answer.

Explanation

The epiglottis is a cartilaginous flap that folds over the glottis during swallowing so that food and liquid are directed into the esophagus instead of the trachea. Patients who are unresponsive lose this protective reflex and are at high risk for aspiration, which is why airway adjuncts and proper positioning matter.

Question 2Airway, Respiration & Ventilation

A nasal cannula is generally set at what oxygen flow rate?

  1. 10 to 15 L/min
  2. 1 to 6 L/min Correct answer.
  3. 6 to 10 L/min
  4. 15 to 25 L/min

Explanation

A nasal cannula delivers low-concentration oxygen, roughly 24% to 44%, at flows of 1 to 6 L/min. Flows above about 6 L/min do not meaningfully raise the inspired oxygen concentration and tend to dry and irritate the nasal passages.

Question 3Airway, Respiration & Ventilation

What is the maximum time you should suction an adult's airway continuously?

  1. 5 seconds
  2. There is no limit if the catheter keeps moving
  3. 15 seconds Correct answer.
  4. 30 seconds

Explanation

Suctioning removes oxygen along with secretions, so an adult should be suctioned for no more than about 15 seconds per attempt (10 seconds for a child, 5 seconds for an infant). Prolonged suctioning can cause hypoxia, vagal-mediated bradycardia, and mucosal trauma.

Question 4Airway, Respiration & Ventilation

When ventilating an adult with a bag-valve mask, each delivered breath should last about:

  1. One half second
  2. 3 seconds
  3. 4 seconds
  4. 1 second Correct answer.

Explanation

Each ventilation should be delivered over about 1 second with only enough volume to produce visible chest rise. Faster or more forceful breaths raise airway pressure and force air into the stomach, promoting gastric distention and aspiration.

Question 5Airway, Respiration & Ventilation

An oropharyngeal airway is most appropriate for which patient?

  1. An alert patient with an intact cough reflex
  2. A conscious patient with mild dyspnea
  3. An unresponsive patient without a gag reflex Correct answer.
  4. A semiconscious patient who is gagging

Explanation

An oropharyngeal airway holds the tongue away from the posterior pharynx in a patient who is unresponsive and has no gag reflex. If the gag reflex is intact, the device stimulates gagging, vomiting, and possible laryngospasm.

Question 6Airway, Respiration & Ventilation

Which respiratory rate is normal for a resting adult?

  1. 8 to 12 breaths/min
  2. 24 to 32 breaths/min
  3. 20 to 28 breaths/min
  4. 12 to 20 breaths/min Correct answer.

Explanation

A normal resting adult respiratory rate is about 12 to 20 breaths per minute. Rates outside this range suggest distress, fatigue, or a compensatory response, and a rate that falls as the patient tires is an ominous sign.

Question 7Airway, Respiration & Ventilation

Which airway maneuver should you use for an unresponsive patient with suspected cervical spine injury?

  1. Head tilt–neck lift
  2. Head tilt–chin lift
  3. Jaw thrust Correct answer.
  4. Neck hyperextension

Explanation

The jaw thrust displaces the mandible forward to lift the tongue while the head and neck are held in neutral alignment, minimizing movement of the injured spine. Manual stabilization is maintained throughout the maneuver.

Question 8Airway, Respiration & Ventilation

An adult choking victim becomes unresponsive. After you lower him to the ground, you should:

  1. Start CPR, beginning with compressions Correct answer.
  2. Deliver five back blows
  3. Perform a blind finger sweep
  4. Begin abdominal thrusts

Explanation

Once a choking victim is unresponsive, standard CPR begins with chest compressions, which can generate enough pressure to expel the obstruction. When you open the airway to give breaths, you look for and remove any visible object, but blind finger sweeps are never performed.

Question 9Airway, Respiration & Ventilation

A normal end-tidal carbon dioxide reading for a healthy adult is approximately:

  1. 20 to 30 mmHg
  2. 10 to 20 mmHg
  3. 35 to 45 mmHg Correct answer.
  4. 50 to 60 mmHg

Explanation

End-tidal CO2 normally approximates arterial CO2 at about 35 to 45 mmHg in a healthy, adequately ventilated adult. Values outside this range suggest hyperventilation, hypoventilation, poor perfusion, or a problem with the airway device.

Question 10Airway, Respiration & Ventilation

You should avoid inserting a nasopharyngeal airway in a patient with which condition?

  1. A history of asthma
  2. A simple wrist fracture
  3. Chronic obstructive pulmonary disease
  4. Suspected basilar skull fracture Correct answer.

Explanation

Severe midface trauma or a suspected basilar skull fracture raises the risk that a nasal airway will pass through a fracture into the cranial vault. In that situation, an oropharyngeal airway is used if the patient has no gag reflex, or the airway is managed by other means.

Question 11Airway, Respiration & Ventilation

Pulse oximetry may give a falsely reassuring reading in a patient with:

  1. A heart rate of 80 beats/min
  2. Normal skin temperature
  3. Carbon monoxide poisoning Correct answer.
  4. A respiratory rate of 16/min

Explanation

Carbon monoxide binds hemoglobin far more readily than oxygen, and a standard pulse oximeter cannot tell the difference, so the saturated hemoglobin reads near normal while tissue oxygen delivery is severely impaired. Poor perfusion, nail polish, and motion can make readings unreliable in other ways.

Question 12Airway, Respiration & Ventilation

Why is two-rescuer bag-valve-mask ventilation preferred over one-rescuer technique?

  1. It removes the need for an airway
  2. It raises the delivered oxygen percentage
  3. Better mask seal and tidal volume Correct answer.
  4. It allows faster ventilation rates

Explanation

With two rescuers, one person uses both hands to hold the mask and maintain a tight seal while the other squeezes the bag with both hands. This combination reliably delivers a larger tidal volume than a single rescuer juggling mask seal and bag compression.

Question 13Airway, Respiration & Ventilation

Gastric distention during bag-valve-mask ventilation is most often caused by:

  1. A mask that is too small
  2. Ventilation with room air
  3. Excessive ventilatory rate or volume Correct answer.
  4. A sniffing head position

Explanation

Ventilating too forcefully or too rapidly raises pharyngeal pressure above the esophageal opening pressure, forcing air into the stomach. Gastric distention then elevates the diaphragm, reduces lung volumes, and increases the risk of vomiting and aspiration.

Question 14Airway, Respiration & Ventilation

CPAP is most appropriate for which patient?

  1. A patient with a systolic BP of 70 mmHg
  2. An awake patient in respiratory distress Correct answer.
  3. An apneic patient with no gag reflex
  4. An unresponsive patient who is vomiting

Explanation

CPAP keeps the alveoli open and improves oxygenation in a patient who is awake, alert, protecting the airway, and maintaining adequate blood pressure, such as in pulmonary edema or a COPD exacerbation. It is contraindicated in apnea, inability to protect the airway, vomiting, and hypotension.

Question 15Airway, Respiration & Ventilation

During CPR for an adult with an advanced airway in place, how often should you give ventilations?

  1. Once every 3 seconds
  2. Twice after every 30 compressions
  3. Once every 10 seconds
  4. Once every 6 seconds Correct answer.

Explanation

Once an advanced airway is in place, compressions become continuous and ventilations are given at a rate of about 10 per minute, or one breath every 6 seconds. Pausing compressions to deliver breaths is no longer necessary.

Question 16Airway, Respiration & Ventilation

When positioning an infant's airway, you should:

  1. Use a sniffing position with slight extension Correct answer.
  2. Place the infant face down
  3. Flex the neck toward the chest
  4. Hyperextend the neck fully

Explanation

An infant's large occiput and soft, compliant trachea make excessive neck extension likely to kink and occlude the airway. A sniffing position with only slight extension, sometimes aided by a small pad under the shoulders, aligns the airway properly.

Question 17Airway, Respiration & Ventilation

You cannot get chest rise when ventilating a patient through a tracheostomy stoma. What should you do?

  1. Increase the rate and force of each ventilation
  2. Insert an oropharyngeal airway into the mouth
  3. Suction the stoma continuously for 30 seconds
  4. Seal the stoma and ventilate the mouth Correct answer.

Explanation

If the stoma cannot be ventilated, air is likely escaping through the upper airway. Occluding the stoma and ventilating through the mouth and nose while maintaining a mask seal provides an alternative route to the lungs.

Question 18Airway, Respiration & Ventilation

A nonrebreather mask should be set at what flow rate to deliver a high concentration of oxygen?

  1. 1 to 4 L/min
  2. 6 to 8 L/min
  3. 2 to 6 L/min
  4. 10 to 15 L/min Correct answer.

Explanation

A nonrebreather mask needs a flow of 10 to 15 L/min to keep the reservoir bag inflated and deliver oxygen concentrations of about 90% or more. Lower flows allow the bag to collapse and the patient to rebreathe exhaled air.

Question 19Airway, Respiration & Ventilation

How do you size an oropharyngeal airway?

  1. From the nostril to the tip of the chin
  2. From the chin to the sternal notch
  3. From the nose to the earlobe
  4. Corner of the mouth to the earlobe Correct answer.

Explanation

An oropharyngeal airway is measured from the corner of the mouth to the earlobe or the angle of the jaw. A device that is too long can push the epiglottis down and obstruct the airway, while one that is too short can push the tongue backward.

Question 20Airway, Respiration & Ventilation

A patient has occasional, slow, gasping breaths and no detectable pulse. You should:

  1. Provide oxygen by nasal cannula
  2. Coach the patient to breathe faster
  3. Apply a nonrebreather mask
  4. Begin CPR and positive pressure ventilation Correct answer.

Explanation

Agonal gasps are not effective breathing and are treated as cardiac arrest. The patient needs immediate chest compressions with positive pressure ventilations rather than supplemental oxygen by a spontaneous-breathing device.

Question 21Airway, Respiration & Ventilation

During transport, the end-tidal CO2 reading of an intubated patient suddenly drops to near zero. What is the most likely cause?

  1. Improved cardiac output and perfusion
  2. Tube displacement from the trachea Correct answer.
  3. A gradually rising body temperature
  4. Slight hyperventilation of the patient

Explanation

An abrupt fall in end-tidal CO2 to near zero in a previously stable intubated patient most often means the tube is no longer in the trachea, either dislodged or esophageal. Immediate reassessment of tube position and ventilation is required.

Question 22Airway, Respiration & Ventilation

An adult is breathing 12 times per minute with a tidal volume of 500 mL. What is the minute volume?

  1. 4 L/min
  2. 6 L/min Correct answer.
  3. 8 L/min
  4. 12 L/min

Explanation

Minute volume is the respiratory rate multiplied by the tidal volume: 12 breaths per minute times 0.5 L equals 6 L/min. Minute volume reflects total ventilation and falls when either rate or depth decreases.

Question 23Airway, Respiration & Ventilation

A patient with COPD in severe respiratory distress has an SpO2 of 82%. What is the most appropriate action?

  1. Give oxygen only if the heart rate is below 100/min
  2. Administer oxygen and titrate to the patient's response Correct answer.
  3. Withhold oxygen to avoid suppressing the hypoxic drive
  4. Apply a nasal cannula at 1 L/min and reassess in 15 minutes

Explanation

Hypoxemia kills faster than hypercapnia, so oxygen is never withheld from a hypoxic patient with COPD. Oxygen is administered and the dose is titrated to clinical response while watching for signs of hypoventilation and drowsiness.

Question 24Airway, Respiration & Ventilation

Which method most reliably confirms and continuously monitors advanced airway placement?

  1. Coloration of the skin
  2. Chest rise with each ventilation
  3. Auscultation of the epigastrium
  4. Continuous waveform capnography Correct answer.

Explanation

Continuous waveform capnography detects exhaled CO2 breath by breath, confirming tracheal placement and revealing dislodgement the moment it occurs. Auscultation and chest rise are helpful secondary checks but are intermittent and less sensitive.

Question 25Airway, Respiration & Ventilation

Which finding in a patient with facial burns suggests impending airway obstruction?

  1. A dry cough and mild sore throat
  2. Blisters on the forearm
  3. First-degree burns of the face
  4. Hoarseness and inspiratory stridor Correct answer.

Explanation

Hoarseness and inspiratory stridor indicate edema narrowing the upper airway in a burn patient, and progression can be rapid. Early advanced airway placement is warranted before swelling makes intubation impossible.

Question 26Airway, Respiration & Ventilation

Which structure normally prevents food and liquid from entering the trachea during swallowing?

  1. The cricoid cartilage
  2. The soft palate
  3. The vocal cords
  4. The epiglottis Correct answer.

Explanation

The epiglottis is a flap of tissue that folds down over the glottic opening during swallowing, diverting material into the esophagus. When a patient loses protective reflexes, this mechanism fails and the airway is at risk for aspiration.

Question 27Airway, Respiration & Ventilation

A nasal cannula is typically set at what oxygen flow rate?

  1. 1 to 6 L/min Correct answer.
  2. 10 to 15 L/min
  3. 6 to 10 L/min
  4. 15 L/min or more

Explanation

A nasal cannula delivers low-flow oxygen at roughly 1 to 6 L/min, producing an inspired oxygen concentration of about 24% to 44%. Higher flows do not reliably increase the fraction delivered and tend to dry and irritate the nasal mucosa.

Question 28Airway, Respiration & Ventilation

When ventilating an adult with a bag-valve-mask, you should squeeze the bag:

  1. for a full 3 seconds with each breath
  2. until the bag is completely emptied each time
  3. as forcefully as possible with both hands
  4. only enough to produce visible chest rise Correct answer.

Explanation

The goal of ventilation is adequate volume at an appropriate rate, and visible chest rise confirms that volume is being delivered. Excessive force or full bag emptying increases the risk of gastric inflation and barotrauma without improving oxygenation.

Question 29Airway, Respiration & Ventilation

Which finding is an early sign of hypoxia?

  1. Restlessness and anxiety Correct answer.
  2. Cyanosis of the fingertips
  3. A heart rate that falls below 50/min
  4. A respiratory rate that drops below 8/min

Explanation

Early hypoxia commonly presents with altered mental status such as restlessness, agitation, and anxiety because the brain is sensitive to falling oxygen levels. Cyanosis and bradycardia are late, unreliable signs that appear after compensation has failed.

Question 30Airway, Respiration & Ventilation

When suctioning the oropharynx of an adult, each attempt should last no longer than:

  1. 30 seconds
  2. 45 seconds
  3. 15 seconds Correct answer.
  4. 60 seconds

Explanation

Suctioning removes air along with secretions, so the attempt is limited to about 15 seconds in adults to prevent hypoxia and vagal-induced bradycardia. The patient should be reoxygenated between attempts, and suction is applied only while withdrawing the catheter.

Question 31Airway, Respiration & Ventilation

You should withhold an oropharyngeal airway from a patient who:

  1. is deeply unresponsive and does not gag
  2. has snoring respirations with no gag reflex
  3. gags when you insert a tongue blade Correct answer.
  4. has a suspected cervical spine injury

Explanation

An oropharyngeal airway is intended for patients without a gag reflex; inserting one in a patient who gags can trigger vomiting, laryngospasm, and aspiration. A patient who gags still has protective reflexes and should be managed with positioning and suctioning instead.

Question 32Airway, Respiration & Ventilation

A patient with a partial upper airway obstruction is most likely to have which breath sound?

  1. Inspiratory stridor Correct answer.
  2. Crackles at the lung bases
  3. Absent breath sounds on one side
  4. Wheezing throughout both lungs

Explanation

Stridor is a harsh sound heard on inspiration that reflects turbulent flow through a narrowed upper airway, such as the larynx or trachea. Wheezing and crackles arise from the lower airways and alveoli, and unilateral absent sounds suggest a pleural or bronchial problem.

Question 33Airway, Respiration & Ventilation

How should you determine the proper length of a suction catheter for an adult?

  1. From the chin to the umbilicus
  2. From the nostril to the sternal notch
  3. From the corner of the mouth to the earlobe Correct answer.
  4. From the tip of the nose to the earlobe

Explanation

Measuring from the corner of the mouth to the earlobe estimates the distance to the posterior pharynx so the catheter reaches secretions without being inserted blindly. The nose-to-earlobe measurement is used for sizing a nasopharyngeal airway instead.

Question 34Airway, Respiration & Ventilation

The main purpose of applying cricoid pressure during positive pressure ventilation is to:

  1. lift the tongue off the posterior pharyngeal wall
  2. stimulate the patient to resume spontaneous breathing
  3. reduce the risk of gastric inflation and aspiration Correct answer.
  4. improve the mask seal against the patient's face

Explanation

Pressure on the cricoid ring compresses the esophagus against the cervical spine, limiting air entry into the stomach and reducing the chance of regurgitation and aspiration. It does not open the airway or affect the mask seal.

Question 35Airway, Respiration & Ventilation

An adult with a palpable pulse is not breathing adequately. How often should you deliver a ventilation?

  1. Once every 15 seconds
  2. Once every 2 seconds
  3. Once every 10 seconds
  4. Once every 6 seconds Correct answer.

Explanation

For an adult with a pulse who needs assisted ventilation, breaths are given about once every 6 seconds, or roughly 10 per minute. This rate supports oxygenation while preserving venous return and avoiding the effects of over-ventilation.

Question 36Airway, Respiration & Ventilation

After intubating an adult, the endotracheal tube depth at the teeth is typically:

  1. 21 to 23 cm Correct answer.
  2. 26 to 28 cm
  3. 15 to 17 cm
  4. 18 to 20 cm

Explanation

An adult endotracheal tube is generally secured with the depth marking at the teeth between about 21 and 23 cm, which places the tip above the carina. A depth outside this range warrants reassessment with auscultation and continuous waveform capnography.

Question 37Airway, Respiration & Ventilation

Which finding indicates inadequate breathing in an adult?

  1. Rate of 22/min with mild anxiety after exertion
  2. Rate of 16/min with a wheeze that resolves with rest
  3. Rate of 18/min with clear speech and pink skin
  4. Rate of 28/min with accessory muscle use Correct answer.

Explanation

Accessory muscle use signals increased work of breathing and an inability to meet metabolic demand, which defines inadequate breathing regardless of rate. Rate alone can look acceptable while the patient is tiring.

Question 38Airway, Respiration & Ventilation

An E cylinder reads 2,000 psi and has a cylinder constant of 0.28. At a flow rate of 15 L/min, approximately how long will the cylinder last?

  1. About 90 minutes
  2. About 55 minutes
  3. About 20 minutes
  4. About 37 minutes Correct answer.

Explanation

Cylinder duration equals gauge pressure times the cylinder constant divided by the flow rate: (2,000 x 0.28) / 15, which equals about 37 minutes. This estimate should be recalculated as pressure falls so that oxygen is replaced before it runs out.

Question 39Airway, Respiration & Ventilation

Over-ventilating a patient during bag-valve-mask ventilation is harmful mainly because it:

  1. washes nitrogen out of the alveoli and causes collapse
  2. forces oxygen into the stomach and causes vomiting
  3. lowers carbon dioxide and reduces blood flow to the brain Correct answer.
  4. raises carbon dioxide levels and causes acidosis

Explanation

Excessive ventilation blows off carbon dioxide, producing hypocapnia that constricts cerebral vessels and reduces cerebral perfusion, and it also raises intrathoracic pressure and impairs venous return. Ventilation should be delivered at the recommended rate and volume rather than as fast or as forcefully as possible.

Question 40Airway, Respiration & Ventilation

A patient with an opioid overdose has a respiratory rate of 6/min and an SpO2 of 98% on room air. What is the best explanation for these findings?

  1. Pulse oximetry is unreliable in opioid overdose
  2. Oxygen saturation can be normal while ventilation is inadequate Correct answer.
  3. The reading is falsely high because of poor perfusion
  4. The patient is hyperventilating despite the slow rate

Explanation

Pulse oximetry reflects hemoglobin saturation, not the movement of air, so a patient can be well saturated while hypoventilating and retaining carbon dioxide. This patient needs assisted ventilation with a bag-valve-mask, not oxygen alone.

Question 41Cardiology & Resuscitation

During CPR on an adult in cardiac arrest, chest compressions should be delivered at which rate?

  1. 100 to 120 per minute Correct answer.
  2. 120 to 140 per minute
  3. 80 to 100 per minute
  4. 60 to 80 per minute

Explanation

High-quality adult CPR uses a compression rate of 100 to 120 per minute, which balances forward blood flow against adequate time for the chest to recoil and the heart to refill.

Question 42Cardiology & Resuscitation

What is the recommended compression depth for an adult in cardiac arrest?

  1. About 3 inches (7.5 cm)
  2. About 4 inches (10 cm)
  3. About 1 inch (2.5 cm)
  4. About 2 inches (5 cm) Correct answer.

Explanation

Adult compressions should depress the sternum at least 2 inches (5 cm) while avoiding depths greater than about 2.4 inches (6 cm), because both too-shallow and excessively deep compressions reduce effectiveness or cause injury.

Question 43Cardiology & Resuscitation

Where should the two AED pads be applied on an adult in cardiac arrest?

  1. Both pads on the anterior chest, side by side
  2. Left upper chest and right lower abdomen
  3. Right upper chest and left lateral chest Correct answer.
  4. One pad over the sternum and one on the mid-back

Explanation

The standard adult anterolateral position places one pad below the right clavicle and the other on the left lateral chest at the mid-axillary line, so that current passes through the heart.

Question 44Cardiology & Resuscitation

A rhythm strip contains 9 QRS complexes in a 6-second interval. What is the approximate heart rate?

  1. 45 per minute
  2. 60 per minute
  3. 90 per minute Correct answer.
  4. 30 per minute

Explanation

The 6-second method counts the number of QRS complexes in a 6-second strip and multiplies by 10, giving 9 x 10 = 90 beats per minute.

Question 45Cardiology & Resuscitation

An unresponsive adult makes occasional gasping sounds, and no carotid pulse is felt. How should these gasps be interpreted?

  1. Not normal breathing; begin CPR Correct answer.
  2. Evidence that circulation has returned
  3. A sign of adequate ventilation
  4. A normal breathing pattern in adults

Explanation

Agonal gasps are ineffective respiratory efforts that commonly appear in the first minutes of cardiac arrest and are treated as absent breathing, so compressions should begin immediately.

Question 46Cardiology & Resuscitation

A QRS complex measuring 0.10 seconds is best described as:

  1. Biphasic
  2. Wide
  3. Narrow Correct answer.
  4. Indeterminate

Explanation

A QRS duration less than 0.12 seconds is narrow, which suggests the impulse reached the ventricles through the normal conduction system rather than through a ventricular or accessory pathway.

Question 47Cardiology & Resuscitation

An adult with chest pain and suspected acute coronary syndrome has no aspirin allergy and can swallow safely. Which aspirin administration is appropriate?

  1. Aspirin 650 mg rectally
  2. Aspirin 1000 mg intravenously
  3. Aspirin 324 mg chewed Correct answer.
  4. Aspirin 81 mg enteric-coated, swallowed whole

Explanation

Chewed non-enteric-coated aspirin in the 162 to 325 mg range is given because chewing accelerates absorption and produces rapid platelet inhibition during suspected ACS.

Question 48Cardiology & Resuscitation

A single rescuer is performing CPR on an adult without an advanced airway in place. What compression-to-ventilation ratio should be used?

  1. 15:2
  2. 5:1
  3. 30:2 Correct answer.
  4. 50:2

Explanation

Adult CPR without an advanced airway uses 30 compressions to 2 ventilations for both single and multiple rescuers, which limits interruptions in chest compressions.

Question 49Cardiology & Resuscitation

An adult has a heart rate of 38 per minute, a blood pressure of 78/44, and remains symptomatic after atropine. What is the most appropriate next intervention?

  1. Adenosine 6 mg rapid IV push
  2. Transcutaneous pacing Correct answer.
  3. Synchronized cardioversion at 100 J
  4. Diltiazem 15 mg IV

Explanation

Symptomatic bradycardia that persists after atropine, or that involves high-degree block, is treated with transcutaneous pacing while the cause is addressed.

Question 50Cardiology & Resuscitation

What is the recommended atropine regimen for symptomatic adult bradycardia?

  1. 0.5 mg IV every 10 minutes, max 1 mg
  2. 3 mg IV as a single dose
  3. 1 mg IV every 3 to 5 minutes, max 3 mg Correct answer.
  4. 0.1 mg/kg IV as a single dose

Explanation

Atropine is given as 1 mg IV every 3 to 5 minutes up to a total of 3 mg; doses below 0.5 mg can paradoxically slow the heart further.