EMT-B Ch. 9

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Which of the following statements regarding normal gas exchange in the lungs is
correct?
A. The oxygen content in the alveoli is highest during the exhalation phase.
B. Oxygen and carbon dioxide diffuse across the alveolar walls and capillaries.
C. The actual exchange of oxygen and carbon dioxide occurs in the capillaries.
D. Blood that returns to the lungs from the body has a low carbon dioxide content.

B

Which of the following structures is NOT found in the upper airway?
A. larynx
B. pharynx
C. bronchus
D. oropharynx

C

The leaf-shaped structure located superior to the larynx is called the:
A. epiglottis.
B. vallecula.
C. cricoid ring.
D. thyroid cartilage

A

The __________ cartilage is a firm ring that forms the inferior part of the larynx.
A. cricoid
B. thyroid
C. laryngeal
D. pyriform

A

Structures of the lower airway include all of the following, EXCEPT the:
A. alveoli.
B. trachea.
C. epiglottis.
D. bronchioles.

C

The actual exchange of oxygen and carbon dioxide occurs in the:
A. bronchioles.
B. alveolar sacs.
C. apex of the lung.
D. pulmonary capillaries.

B

Which of the following structures is contained within the mediastinum?
A. lungs
B. larynx
C. bronchioles
D. esophagus

D

The physical act of moving air into and out of the lungs is called:
A. diffusion.
B. ventilation.
C. respiration.
D. oxygenation.

B

Inhalation occurs when the:
A. diaphragm and intercostal muscles relax and cause an increase in intrathoracic
pressure.
B. diaphragm and intercostal muscles ascend and cause an increase in intrathoracic
pressure.
C. diaphragm and intercostal muscles contract and cause a decrease in intrathoracic
pressure.
D. diaphragm ascends and the intercostal muscles contract, causing a decrease in
intrathoracic pressure.

C

The diaphragm functions as an involuntary muscle when a person:
A. sleeps.
B. coughs.
C. takes a deep breath.
D. holds his or her breath.

A

The partial pressure of oxygen in the alveoli is _______ mm Hg, while the partial
pressure of carbon dioxide in the alveoli is _______ mm Hg.
A. 70, 28
B. 88, 30
C. 90, 50
D. 104, 40

D

Tidal volume is defined as the volume of air that:
A. is moved through the lungs in a single minute.
B. moves into or out of the lungs in a single breath.
C. remains in the lungs following a complete exhalation.
D. is forced into the lungs as a result of positive pressure.

B

What is the minute volume of a patient with a tidal volume of 500 mL, a dead space
volume of 150 mL, and a respiratory rate of 16 breaths/min?
A. 5,600 mL
B. 6,000 mL
C. 7,400 mL
D. 8,000 mL

A

Which of the following factors will cause a decreased minute volume in an adult?
A. shallow breathing
B. increased tidal volume
C. respirations of 20 breaths/min
D. slight decrease in respiratory rate

A

In contrast to inhalation, exhalation:
A. requires muscular effort to effectively expel air from the lungs.
B. is a passive process caused by increased intrathoracic pressure.
C. occurs when the diaphragm lowers and expels air from the lungs.
D. is an active process caused by decreased intrathoracic pressure.

B

Hypoxia is MOST accurately defined as:
A. low venous oxygen levels.
B. a decrease in arterial oxygen levels.
C. an increase in carbon dioxide in the blood.
D. inadequate oxygen to the tissues and cells.

D

The hypoxic drive—the primary stimulus to breathe for patients with certain chronic
respiratory diseases—is influenced by:
A. high blood oxygen levels.
B. low blood oxygen levels.
C. low blood carbon dioxide levels.
D. high blood carbon dioxide levels.

B

Which of the following is a late sign of hypoxia?
A. anxiety
B. cyanosis
C. tachycardia
D. restlessness

B

Which of the following statements regarding oxygenation and ventilation is correct?
A. In carbon monoxide (CO) poisoning, ventilation is impaired because CO binds to
oxygen very quickly.
B. Oxygenation is the movement of air into and out of the lungs, whereas ventilation is
the exchange of gases.
C. In mines or confined places, where oxygen levels are low, ventilation may continue
despite adequate oxygenation.
D. Oxygenation without adequate ventilation can occur in climbers who quickly ascend
to an altitude of lower atmospheric pressure.

C

Each cell of the body combines nutrients and oxygen and produces energy and waste
products through a process called:
A. respiration.
B. ventilation.
C. metabolism.
D. oxygenation.

C

The process of exchanging oxygen and carbon dioxide between the alveoli and the
blood of the capillaries is called:
A. external respiration.
B. cellular metabolism.
C. pulmonary ventilation.
D. alveolar ventilation.

A

Gas exchange in the lungs is facilitated by:
A. adequate amounts of surfactant.
B. water or blood within the alveoli.
C. surfactant-destroying organisms.
D. pulmonary capillary constriction.

A

In the presence of oxygen, the mitochondria of the cells convert glucose into energy
through a process called:
A. perfusion.
B. respiration.
C. aerobic metabolism.
D. anaerobic metabolism.

C

Without adequate oxygen, the body’s cells:
A. rely solely on glucose, which is completely converted into adenosine triphosphate
(ATP).
B. cease metabolism altogether, resulting in carbon dioxide accumulation in the blood.
C. begin to metabolize fat, resulting in the production and accumulation of ketoacids.
D. incompletely convert glucose into energy, and lactic acid accumulates in the blood.

D

The primary waste product of aerobic metabolism is:
A. lactic acid.
B. pyruvic acid.
C. carbon dioxide.
D. adenosine triphosphate.

C

Central chemoreceptors located in the medulla provide feedback to increase the rate
and depth of breathing when they sense:
A. slight elevations in carbon dioxide or a decrease in the pH of the cerebrospinal fluid.
B. slight decreases in carbon dioxide and an increase in the pH of the cerebrospinal
fluid.
C. decreased levels of oxygen in the blood and an increase in the pH of the cerebrospinal
fluid.
D. increased levels of oxygen in the blood and a decrease in the pH of the cerebrospinal
fluid.

A

A ventilation/perfusion (V/Q ratio) mismatch occurs when:
A. ventilation is inadequate due to a traumatic injury or medical condition, which results
in an impairment in pulmonary gas exchange.
B. a disruption in blood flow inhibits the exchange of oxygen and carbon dioxide in the
lungs, even though the alveoli are filled with fresh oxygen.
C. ventilation is compromised, resulting in the accumulation of carbon dioxide in the
bloodstream, alveoli, and the tissues and cells of the body.
D. a traumatic injury or medical condition impairs the body’s ability to effectively bring
oxygen into the lungs and remove carbon dioxide from the body.

B

If ventilation is impaired, carbon dioxide levels in the bloodstream will increase. This
condition is called:
A. acidosis.
B. hypoxia.
C. hypoxemia.
D. hypercarbia.

D

Intrapulmonary shunting occurs when:
A. the presence of pulmonary surfactant causes a decrease in alveolar surface tension,
thus impairing the exchange of gases in the lungs.
B. a decrease in respiratory rate and depth causes carbon dioxide accumulation in the
alveoli and an overall decrease in blood oxygen levels.
C. blood coming from the right side of the heart bypasses nonfunctional alveoli and
returns to the left side of the heart in an unoxygenated state.
D. any impairment in circulatory function causes a reduced ability for oxygen and
carbon dioxide to diffuse across the alveolar-capillary membrane.

C

An adult at rest should have a respiratory rate that ranges between:
A. 8 and 15 breaths/min.
B. 10 and 18 breaths/min.
C. 12 and 20 breaths/min.
D. 16 and 24 breaths/min.

C

Which of the following patients is breathing adequately?
A. a conscious male with respirations of 19 breaths/min and pink skin
B. a conscious female with facial cyanosis and rapid, shallow respirations
C. a conscious male with respirations of 18 breaths/min and reduced tidal volume
D. an unconscious 52-year-old female with snoring respirations and cool, pale skin

A

Which of the following statements regarding breathing adequacy is correct?
A. Patients with a grossly irregular breathing pattern usually do not require assisted
ventilation.
B. The single most reliable sign of breathing adequacy in the adult is his or her
respiratory rate.
C. Patients breathing shallowly may require assisted ventilation despite a normal
respiratory rate.
D. A patient with slow respirations and adequate depth will experience an increase in
minute volume.

C

Which of the following would NOT cause a decrease in tidal volume?
A. shallow breathing
B. deep respirations
C. irregular breathing
D. agonal respirations

B

Irregular respirations characterized by an increasing rate and depth of breathing
followed by periods of apnea are called:
A. ataxic respirations.
B. agonal respirations.
C. eupneic respirations.
D. Cheyne-Stokes respirations.

D

An unconscious patient found in a prone position must be placed in a supine position
in case he or she:
A. requires cardiopulmonary resuscitation (CPR).
B. begins to vomit.
C. regains consciousness.
D. has increased tidal volume.

A

You are dispatched to a residence where a middle-aged man was found unconscious
in his front yard. There are no witnesses who can tell you what happened. You find
him in a prone position; his eyes are closed and he is not moving. Your FIRST action
should be to:
A. palpate for the presence of a carotid pulse.
B. log roll him as a unit to a supine position.
C. assess the rate and quality of his breathing.
D. open his airway with a jaw-thrust maneuver.

B

What is the MOST common cause of airway obstruction in an unconscious patient?
A. vomitus
B. the tongue
C. blood clots
D. aspirated fluid

B

In which of the following patients would the head tilt-chin lift maneuver be the
MOST appropriate method of opening the airway?
A. a 24-year-old male who is found unconscious at the base of a tree
B. a 37-year-old female who is found unconscious in her bed
C. a 45-year-old male who is semiconscious after falling 20 feet
D. a 50-year-old male who is unconscious following head trauma

B

The jaw-thrust maneuver is used to open the airway of patients with suspected:
A. mandibular fractures.
B. upper airway swelling.
C. cervical spine injuries.
D. copious oral secretions.

C

Which of the following patients would MOST likely require insertion of an
oropharyngeal airway?
A. a 33-year-old semiconscious patient with reduced tidal volume
B. a 40-year-old unconscious patient with slow, shallow respirations
C. a 51-year-old confused patient with severely labored respirations
D. a 64-year-old conscious patient with rapid and deep respirations

B

A 19-year-old female is found unconscious by her roommate. Your primary
assessment reveals that her breathing is inadequate. As you insert an oropharyngeal
airway, she begins to gag violently. You should:
A. continue to insert the airway as you suction her oropharynx.
B. remove the airway and be prepared to suction her oropharynx.
C. insert the airway no further but leave it in place as a bite block.
D. select a smaller oropharyngeal airway and attempt to insert it.

B

To select the proper size oropharyngeal airway, you should measure from the:
A. corner of the mouth to the earlobe.
B. center of the mouth to the posterior ear.
C. corner of the mouth to the superior ear.
D. angle of the jaw to the center of the mouth.

A

The nasopharyngeal airway is MOST beneficial because it:
A. can effectively stabilize fractured nasal bones if it is inserted properly.
B. is generally well tolerated in conscious patients with an intact gag reflex.
C. effectively maintains the airway of a patient in cardiopulmonary arrest.
D. can maintain a patent airway in a semiconscious patient with a gag reflex.

D

The MOST serious complication associated with using a nasopharyngeal airway in a
patient with trauma to the head or face is:
A. fracturing the septum.
B. damaging the turbinates.
C. penetrating the cranium.
D. causing severe bleeding.

C

A nasopharyngeal airway is inserted:
A. with the bevel facing the septum if inserted into the right nare.
B. into the larger nostril with the tip pointing away from the septum.
C. with the bevel pointing downward if inserted into the left nare.
D. into the smaller nostril with the tip following the roof of the nose.

A

A 71-year-old male is semiconscious following a sudden, severe headache. There is
vomitus on his face and his respirations are slow and shallow. The EMT must
immediately:
A. insert a nasopharyngeal airway.
B. perform oropharyngeal suctioning.
C. apply oxygen via a nonrebreathing mask.
D. assist the patient’s ventilations with a bag-mask device.

B

When testing a mechanical suctioning unit, you should turn on the device, clamp the
tubing, and ensure that it generates a vacuum pressure of more than:
A. 100 mm Hg.
B. 200 mm Hg.
C. 300 mm Hg.
D. 400 mm Hg.

C

The MOST significant complication associated with oropharyngeal suctioning is:
A. oral abrasions from vigorous suctioning.
B. hypoxia due to prolonged suction attempts.
C. clogging of the catheter with thick secretions.
D. vomiting from stimulating the anterior airway.

B

Proper technique for suctioning the oropharynx of an adult patient includes:
A. continuously suctioning patients with copious oral secretions.
B. suctioning while withdrawing the catheter from the oropharynx.
C. removing large, solid objects with a tonsil-tip suction catheter.
D. suctioning for up to 1 minute if the patient is well oxygenated.

B

You have inserted an oral airway and are ventilating an apneic woman with a bag-
mask device. She suddenly begins regurgitating large amounts of vomit. You should:
A. perform a finger sweep of her mouth.
B. insert a nasal airway and then suction her mouth.
C. roll her onto her side and remove the oral airway.
D. remove the oral airway and suction her oropharynx.

C

A 23-year-old male experienced severe head trauma after his motorcycle collided
with an oncoming truck. He is unconscious, has rapid and shallow breathing, and has
copious bloody secretions in his mouth. How should you manage his airway?
A. Suction his oropharynx with a rigid catheter until all secretions are removed.
B. Insert a nasopharyngeal airway and provide suction and assisted ventilations.
C. Alternate 15 seconds of oral suctioning with 2 minutes of assisted ventilation.
D. Provide continuous ventilations with a bag-mask device to minimize hypoxia.

C

Which of the following patients should you place in the recovery position?
A. a 19-year-old conscious male with a closed head injury and normal respirations
B. a 24-year-old unconscious female who overdosed and has a reduced tidal volume
C. a 31-year-old semiconscious male with low blood sugar and adequate breathing
D. a 40-year-old conscious female with a possible neck injury and regular respirations

C

Which of the following organs or tissues can survive the longest without oxygen?
A. muscle
B. heart
C. liver
D. kidneys

A

The purpose of the pin-indexing system that has been established for compressed gas
cylinders is to:
A. ensure that the correct regulator is used for the cylinder.
B. help you determine what type of oxygen regulator to use.
C. prevent destroying or stripping the threads on the cylinder.
D. reduce the cylinder pressure to a safe and more useful range.

A

The pressure of gas in a full cylinder of oxygen is approximately _______ pounds per
square inch (psi).
A. 500
B. 1,000
C. 1,500
D. 2,000

D

Which of the following oxygen flowmeters is NOT affected by gravity and can be
used in any position when attached to an oxygen cylinder?
A. vertical-position flowmeter
B. Bourdon-gauge flowmeter
C. ball-and-float flowmeter
D. pressure-compensated flowmeter

B

An oxygen cylinder should be taken out of service and refilled when the pressure
inside it is less than:
A. 200 psi.
B. 500 psi.
C. 1,000 psi.
D. 1,500 psi.

B

Which of the following statements regarding oxygen is correct?
A. Oxygen cylinders must always remain in an upright position.
B. Oxygen is flammable and may explode if under high pressure.
C. Oxygen supports the combustion process and may cause a fire.
D. Oxygen is most safely administered in an enclosed environment.

C

A patient who is suspected of being hypoxic and is breathing adequately should be
given supplemental oxygen with a:
A. nasal cannula.
B. nonrebreathing mask.
C. bag-mask device.
D. mouth-to-mask device.

B

With a good mask-to-face seal and an oxygen flow rate of 15 L/min, the
nonrebreathing mask is capable of delivering up to ______% inspired oxygen.
A. 70
B. 80
C. 90
D. 100

C

Prior to applying a nonrebreathing mask on a patient, you must ensure that the:
A. one-way valve is sealed.
B. flow rate is set at 6 L/min.
C. reservoir bag is fully inflated.
D. patient has reduced tidal volume.

C

At a flow rate of 6 L/min, a nasal cannula can deliver an approximate oxygen
concentration of up to:
A. 24%.
B. 35%.
C. 44%.
D. 52%.

C

The nasal cannula is MOST appropriately used in the prehospital setting:
A. when the patient cannot tolerate a nonrebreathing mask.
B. if the patient’s nasopharynx is obstructed by secretions.
C. if long-term supplemental oxygen administration is required.
D. when the patient breathes primarily through his or her mouth.

A

The main advantage of the Venturi mask is:
A. the ability to adjust the percentage of inspired oxygen when caring for a critically ill
or injured patient.
B. the use of its fine adjustment capabilities in the long-term management of
physiologically stable patients.
C. that it does not contain an oxygen reservoir, so the same percentage of oxygen can
consistently be administered.
D. the ability to adjust the amount of oxygen administered to the patient by increasing
the flow rate on the regulator.

B

A 51-year-old female presents with a sudden onset of difficulty breathing. She is
conscious and alert and able to speak in complete sentences. Her respirations are 22
breaths/min and regular. You should:
A. administer 100% oxygen via a nonrebreathing mask.
B. insert a nasal airway in case her mental status decreases.
C. perform a secondary assessment and then begin treatment.
D. assist her breathing with a bag-mask device and 100% oxygen.

A

What occurs when a patient is breathing very rapidly and shallowly?
A. Minute volume increases because of a marked increase in both tidal volume and
respiratory rate.
B. Air moves primarily in the anatomic dead space and does not participate in
pulmonary gas exchange.
C. Air is forcefully drawn into the lungs due to the negative pressure created by the rapid
respirations.
D. The majority of tidal volume reaches the lungs and diffuses across the alveolar-
capillary membrane.

B

As the single EMT managing an apneic patient’s airway, the preferred initial method
of providing ventilations is the:
A. mouth-to-mouth technique.
B. one-person bag-mask device.
C. manually triggered ventilation device.
D. mouth-to-mask technique with a one-way valve.

D

You and your partner are treating a 66-year-old man who experienced a sudden onset
of respiratory distress. He is conscious but is unable to follow simple verbal
commands. Further assessment reveals that his breathing is severely labored and his
oxygen saturation is 80%. You should:
A. attempt to insert an oropharyngeal airway.
B. assist his ventilations with a bag-mask device.
C. apply a continuous positive airway pressure (CPAP) device and monitor his
breathing.
D. apply high-flow oxygen via nonrebreathing mask.

B

Which of the following statements regarding positive-pressure ventilation is correct?
A. Positive-pressure ventilation allows blood to naturally be pulled back to the heart
from the body.
B. With positive-pressure ventilation, more volume is required to have the same effects
as normal breathing.
C. To prevent hypotension, the EMT should increase the rate and force of positive-
pressure ventilation.
D. Unlike negative-pressure ventilation, positive-pressure ventilation does not affect the
esophageal opening pressure.

B

How does positive-pressure ventilation affect cardiac output?
A. There is no effect on cardiac output because positive-pressure ventilation is the act of
normal breathing.
B. It decreases intrathoracic pressure, which facilitates venous return to the heart and
increases cardiac output.
C. It causes pressure in the chest to decrease, which increases stroke volume and cardiac
output.
D. It increases intrathoracic pressure, which decreases venous return to the heart and
causes a decrease in cardiac output.

D

You are ventilating a 40-year-old uninjured man who is apneic but has a pulse. When
your partner reassesses his blood pressure, he notes that it has decreased significantly
from previous readings. You elevate the patient’s legs, but this action has no effect.
You should:
A. reevaluate the rate and volume of your ventilations.
B. perform a head-to-toe assessment to look for bleeding.
C. increase the volume of your ventilations and reassess his blood pressure.
D. ensure that you are delivering one breath every 3 to 5 seconds.

A

You are performing mouth-to-mask ventilations with oxygen connected and set at a
flow rate of 15 L/min. What percentage of oxygen is your patient receiving?
A. 45%
B. 55%
C. 65%
D. 75%

B

You and your partner are caring for a critically injured patient. Your partner is
controlling severe bleeding from the patient’s lower extremities as you attempt
ventilations with a bag-mask device. After repositioning the mask several times, you
are unable to effectively ventilate the patient. You should:
A. begin ventilations using the mouth-to-mask technique.
B. hyperextend the patient’s head and reattempt ventilations.
C. continue attempted ventilations and transport immediately.
D. suction the patient’s airway for 30 seconds and reattempt ventilations.

A

Which of the following statements regarding the one-person bag-mask device
technique is correct?
A. Bag-mask ventilations should be delivered every 2 seconds when the device is being
operated by one person.
B. The C-clamp method of holding the mask to the face is not effective when ventilating
a patient with a bag-mask device.
C. Adequate tidal volume is often difficult to achieve when one EMT is operating the
bag-mask device.
D. The bag-mask device delivers more tidal volume and a higher oxygen concentration
than the mouth-to-mask technique.

C

Despite your attempts to coach a conscious young female’s respirations, she
continues to hyperventilate with a marked reduction in tidal volume. You should:
A. restrain her and provide ventilatory assistance.
B. insert a nasopharyngeal airway and give oxygen.
C. explain to her that you will assist her ventilations.
D. ventilate her at the rate at which she is breathing.

C

All of the following will help minimize the risk of gastric distention when ventilating
an apneic patient with a bag-mask device, EXCEPT:
A. delivering each breath over 1 second.
B. ensuring the appropriate airway position.
C. ventilating the patient at the appropriate rate.
D. increasing the amount of delivered tidal volume.

D

Which of the following is the MOST reliable indicator of adequately performed bag-
mask ventilations in an apneic adult with a pulse?
A. 20 breaths/min being delivered to the adult
B. decreased compliance when squeezing the bag
C. an adult’s heart rate that is consistently increasing
D. adequate rise of the chest when squeezing the bag

D

On which of the following patients would it be MOST appropriate to use the flow-
restricted, oxygen-powered ventilation device?
A. an 8-year-old female with respiratory failure
B. a 21-year-old male with traumatic cardiac arrest
C. a 38-year-old apneic female with blunt chest trauma
D. a 59-year-old male with chronic obstructive pulmonary disease (COPD)

B

How does CPAP improve oxygenation and ventilation in patients with certain
respiratory problems?
A. It forces the alveoli open and pushes more oxygen across the alveolar membrane.
B. It pushes thick, infected pulmonary secretions into isolated areas of the lung tissue.
C. It decreases intrathoracic pressure, which allows more room for the lungs to expand.
D. It prevents alveolar collapse by pushing air into the lungs during the inhalation phase.

A

CPAP is indicated for patients who:
A. have signs of pneumonia but are breathing adequately.
B. are unresponsive and have signs of inadequate ventilation.
C. have pulmonary edema and can follow verbal commands.
D. are hypotensive and have a marked reduction in tidal volume.

C

You are ventilating a patient with a stoma; however, air is escaping from the mouth
and nose. To prevent this, you should:
A. thrust the jaw forward.
B. seal the mouth and nose.
C. ventilate with less pressure.
D. thoroughly suction the stoma.

B

A 37-year-old male has an apparent foreign body airway obstruction. He is conscious
and alert and is coughing forcefully. His skin is pink, warm, and moist. The MOST
appropriate treatment for this patient includes:
A. a series of back blows and chest thrusts.
B. finger sweeps to remove the obstruction.
C. performing a series of abdominal thrusts.
D. encouraging him to cough and transporting.

D

While eating dinner, your partner suddenly grabs his throat and has a panicked look
on his face. He has a weak cough, faint inspiratory stridor, and cyanosis around the
lips. You should:
A. encourage him to cough as forcefully as he can.
B. deliver up to five back blows and reassess him.
C. place him in a supine position and open his airway.
D. stand behind him and administer abdominal thrusts.

D

Which of the following is NOT a possible cause of airway obstruction?
A. relaxation of the tongue
B. aspirated vomitus
C. shallow breathing
D. foreign objects

C

You are ventilating an apneic woman with a bag-mask device. She has dentures,
which are tight-fitting. Adequate chest rise is present with each ventilation, and the
patient’s oxygen saturation reads 96%. When you reassess the patency of her airway,
you note that her dentures are now loose, although your ventilations are still
producing adequate chest rise. You should:
A. remove her dentures, resume ventilations, and assess for adequate chest rise.
B. attempt to replace her dentures so that they fit tightly and resume ventilations.
C. leave her dentures in place, but carefully monitor her for an airway obstruction.
D. remove her dentures at once and increase the rate and volume of your ventilations.

A

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