Deck 14: Regulation of Breathing

Question 1

Which of the following can cause laryngospasm and bradycardia through a vagovagal reflex?
I)bronchoscopy
II)endotracheal intubation
III)tracheal suctioning

A)I
B)I and III
C)I, II, and III
D)I and II

Answer 1

C

Question 2

Which of the following is NOT an effect of J receptor stimulation?

A)deep breathing
B)dyspnea
C)glottic narrowing
D)rapid breathing

Answer 2

A

Question 3

Sensory input to the dorsal respiratory neurons from the lungs, airways, and peripheral chemoreceptors is provided via which nerves?
I)glossopharyngeal
II)phrenic
III)vagus

A)I and II
B)I
C)I and III
D)I, II, and III

Answer 3

C

Question 4

What receptors are known to cause an increase in ventilation when the patient's limbs are moved or cold water is splashed on the patient's face?

A)Irritant receptors
B)J receptors
C)muscle spindles
D)peripheral proprioceptors

Question 5

What reflex is associated with the sensory stimulation of the pulmonary stretch receptors that stimulate a deeper breath upon inspiration?

A)carotid
B)Head's paradoxical
C)Hering-Breuer
D)J receptor

Question 6

What negative responses can be elicited by suctioning a patient's airway?
I)bradycardia
II)coughing
III)laryngospasm
IV)severe bronchospasm

A)I, II, and III
B)II and IV
C)III only
D)I, II, III, and IV

Question 7

Pulmonary J receptors can be stimulated by which of the following?
I)edema
II)inflammatory processes
III)pulmonary vascular congestion

A)I and III
B)I
C)I and III
D)I, II, and III

Question 8

What receptors cause a rapid shallow breathing pattern when stimulated by pulmonary disease?

A)irritant receptors
B)J receptors
C)muscle spindles
D)peripheral proprioceptors

Question 9

In what location are the inspiratory and expiratory centers found?

A)medulla
B)neurons in the cerebellum
C)pons
D)No such centers exist.

Question 10

Failure to switch off the brainstem inspiratory neurons can result in which of the following?

A)apnea
B)apneustic breathing
C)Biot's breathing
D)Cheyne-Stokes breathing

Question 11

The pneumotaxic center controls which of the following?

A)response to changes in blood pH and PCO₂
B)rhythm of the full breathing cycle
C)when inspiration switches off (the inspiratory time)
D)when inspiration switches on (the expiratory time)

Question 12

What centers are located in the pons of the brain stem?
I)apneustic center
II)dorsal respiratory neurons
III)pneumotaxic center

A)I, II, and III
B)II and III
C)I and III
D)I and II

Question 13

Stimulation of the irritant receptors in the lung can result in which of the following?
I)bronchoconstriction
II)coughing
III)narrowing of the glottis

A)I
B)I and III
C)I, II, and III
D)I and III

Question 14

What is the effect when the deflation reflex is stimulated?

A)a strong inspiratory effort
B)expiration is initiated
C)cuts off all inspiratory signals
D)stimulates the termination of expiration

Question 15

What stimulates the Hering-Breuer inflation reflex?

A)the DRG when it is time to end inspiratory efforts
B)the stretch of receptors at high lung volumes
C)the VRG when it is time for inspiration
D)very low lung volumes stimulate inspiration

Question 16

To which anatomic structures do the ventral respiratory centers send motor signals during inspiration?
I)diaphragm
II)larnyx
III)pharynx
IV)sternocleidomastoids

A)I, II, and III
B)II and IV
C)I only
D)I, II, III, and IV

Question 17

The inhibitory neurons that switch off the inspiratory ramp signal are controlled by which of the following?
I)apneustic center
II)pneumotaxic center
III)pulmonary stretch receptors

A)I, II, and III
B)I and II
C)III
D)II and III

Question 18

What receptors are associated with causing coughing, sneezing, and tachypnea when stimulated?

A)irritant receptors
B)J receptors
C)muscle spindles
D)peripheral proprioceptor

Question 19

Which statements describe aspects of the Hering-Breuer reflex?
I.It affects the rate and depth of breathing during exercise.
II.It is only activated at large tidal volumes in normal adults.
III.Its impulses travel via the vagus nerve to the dorsal respiratory groups (DRGs).
IV.Its receptors are located in the large and small airways.

A)I
B)I and II
C)II, III, and IV
D)I, II, III, and IV

Question 20

The medulla oblongata contains which of the following areas?
I)apneustic center
II)dorsal respiratory group neurons (DRGs)III.pneumotaxic center
IV)ventral respiratory group neurons (VRGs)

A)I, II, and III
B)II and IV
C)III only
D)I, II, III, and IV

Question 21

Stimulation to increase ventilation does not occur until the PaO₂ falls below what level?

A)90 mm Hg
B)80 mm Hg
C)70 mm Hg
D)60 mm Hg

Question 22

Why does it take about 24 hours for a full ventilatory response to develop to acute hypoxemia?

A)Initial cerebrospinal fluid alkalemia blunts the hypoxic ventilatory stimulus.
B)Peripheral chemoreceptors are slow to respond to decreased blood oxygen levels.
C)Renal compensation for respiratory alkalosis increases chemoreceptor sensitivity.
D)A full ventilatory response is not possible until after the muscles become fatigued.

Question 23

Adjustment of respiratory muscle contractions to accommodate varying loads is regulated by which of the following?

A)medullary respiratory centers
B)muscle spindle fiber feedback
C)pontine apneustic center
D)pontine pneumotaxic center

Question 24

Which receptors are primarily responsible for the initial increase in ventilation that occurs at the beginning of exercise?

A)carotid chemoreceptors
B)irritant receptors
C)J receptors
D)proprioceptors

Question 25

Which of the following is indirectly responsible for minute-to-minute control of breathing?

A)CO₂ levels
B)HCO₃^- levels
C)lactate levels
D)O₂ levels

Question 26

What group of nerve cells senses and responds to changes in the chemical composition of its fluid environment?

A)chemoreceptors
B)Gamma-efferent system
C)muscle spindle fibers
D)proprioceptors

Question 27

In the face of chronically elevated levels of CO₂, what happens to the response mediated by the central chemoreceptors?

A)It is accentuated or increased.
B)It is muted or decreased.
C)There is no change in the response.
D)There is no way to predict the bodies response.

Question 28

Coexisting arterial hypoxemia, acidemia, and high PaCO₂ (i.e., asphyxia) will have what affect on the peripheral chemoreceptors?

A)There is a decreased drive to breathe.
B)There is a maximal increased drive to breathe.
C)There is insufficient information to make a determination.
D)There is virtually no response.

Question 29

Both anemia and carbon monoxide (CO) poisoning can cause severe hypoxia, yet neither condition results in a major stimulation of breathing. Why is this so?

A)The peripheral chemoreceptors do not respond to low oxygen content.
B)Anemia and CO poisoning depress the peripheral chemoreceptors.
C)Anemia and CO poisoning depress the central chemoreceptors.
D)Anemia and CO cause stagnant hypoxia, not hypoxemia.

Question 30

How should oxygen therapy be administered to chronically hypercapnic patients?

A)avoid giving any supplemental oxygen
B)give as much oxygen as possible (60% to 100%)
C)withhold oxygen until the patient is intubated
D)give as much oxygen as required to maintain adequate oxygenation

Question 31

What is the response of a patient with chronic hypercapnia to a sudden acute rise in carbon dioxide?

A)In almost all of these patients, there will be no response.
B)Their drive to breathe will be increased.
C)This will further depress their respiratory centers.
D)This will induce apnea and sudden death.

Question 32

What has the primary responsibility for sensing and responding to changes in blood levels of CO₂?

A)apneustic centers
B)central chemoreceptors
C)peripheral chemoreceptors
D)pneumotaxic center

Question 33

In what manner would oxygen therapy induce worsening $\dot { V }$ / $\dot { Q }$ mismatch and thus a further elevation in CO₂ in a chronically hypercapnic patient?

A)by improving blood flow to poorly ventilated alveoli
B)by decreasing blood flow to poorly ventilated alveoli
C)causing bronchoconstriction, which worsens gas flow to low $\dot { V }$ / $\dot { Q }$ areas
D)causing bronchodilation, which improves gas flow to poorly ventilated alveoli

Question 34

Which respond more rapidly to high levels of CO₂?

A)aortic chemoreceptors
B)carotid chemoreceptors
C)central chemoreceptors
D)ventral respiratory centers

Question 35

Which of the following centers respond more strongly to high levels of CO₂?

A)aortic chemoreceptors
B)carotid chemoreceptors
C)central chemoreceptors
D)ventral respiratory centers

Question 36

What happens in chronic hypercapnia?
I.The central chemoreceptive response to CO₂ is decreased.
II.The cerebrospinal fluid pH is restored to normal.
III.Responsiveness to increased CO₂ is decreased.

A)I
B)I and II
C)II and III
D)I, II, and II

Question 37

When given high concentrations of oxygen, a patient with chronic hypercapnia may develop a more serious respiratory acidosis. Which of the following might be contributing to the patient's increased PCO₂?
I.worsening ventilation-perfusion ( $\dot { V }$ / $\dot { Q }$ ) balance
II.desensitization of the carotid bodies
III.removal of the hypoxic stimulus

A)I and II
B)I only
C)I and III
D)I, II, and III

Question 38

In the face of hyperoxia, what is the response of the peripheral chemoreceptors to hypercapnia?

A)There is a decreased drive to breathe.
B)There is an increased drive to breathe.
C)There is insufficient information.
D)There is virtually no response.

Question 39

Where are the peripheral chemoreceptors located?
I)in the arch of the aorta
II)in the bifurcations of carotid arteries
III)on the ventrolateral surfaces of the medulla

A)I and II
B)I
C)II and III
D)I, II, and III

Question 40

Which of the following causes hypoxic stimulation of the carotid bodies?
I)large decrease in arterial PO₂
II)large decrease in oxygen content
III)CO₂ poisoning

A)I only
B)I and II
C)I, II, and III
D)I and III

Question 41

While observing a patient's breathing, you note that the depth and rate first increase, then decrease, followed by a period of apnea. Which of the following terms would you use in charting this observation?

A)apneustic breathing
B)Biot's breathing
C)Cheyne-Stokes breathing
D)paradoxic breathing

Question 42

You observe a patient's breathing pattern as very irregular, with periods of breathing interspersed with long periods of apnea. Which of the following terms would you use in charting this observation?

A)apneustic breathing
B)Biot's respiration
C)Cheyne-Stokes breathing
D)Kussmaul's breathing

Question 43

What does apneustic breathing indicate?

A)damage to the cerebrum
B)damage to the pons
C)spinal cord transection
D)vagal nerve damage

Question 44

Which of the following will occur during even strenuous exercise in a normal healthy individual?

A)Blood gases remain stable.
B)The arterial PCO₂ rises.
C)The arterial pH falls.
D)The arterial PO₂ falls.

Question 45

Causes of central neurogenic hyperventilation include which of the following?
I)head trauma
II)inadequate brain blood flow
III)severe brain hypoxia

A)II and III
B)I and II
C)I and III
D)I, II, and III

Question 46

Biot's respiration is most frequently observed in patients with which of the following?

A)congestive heart failure
B)increased intracranial pressure
C)metabolic acidosis
D)peripheral nerve disorders

Question 47

In patients with closed-head injuries, what may happen if the patient has hypercapnia?

A)High CO₂ increases the risk of psychotic events.
B)High CO₂ levels cause cerebral vasodilation and improved oxygenation.
C)Severe cerebral vasoconstriction results in anoxia and stroke.
D)Vasodilation causes increased intracranial pressure and possibly stops blood flow.

Question 48

Cheyne-Stokes breathing may be caused by which of the following?
I)brain injuries
II)congestive heart failure
III)metabolic acidosis

A)I and II
B)II and III
C)I and III
D)I, II, and III