NURS 8022 Structure and Function of the Pulmonary System Huether & McCance: Understanding Pathophysiology, 6th Edition
MULTIPLE CHOICE
1. The
... [Show More] nasopharynx is lined with a ciliated mucosal membrane with a highly vascular blood supply. One function of this membrane is to:
a. absorb air.
b. humidify air.
c. cool air.
d. exchange gases.
ANS: B
These structures are lined with a ciliated mucosa that warms and humidifies inspired air and removes foreign particles from it. Air is not absorbed or cooled by the ciliated mucosal membrane. Gas exchange occurs in the alveoli.
REF: p. 671
2. The nurse is describing the slit-shaped space between the true vocal cords. What term should the nurse use?
a. Glottis
b. Epiglottis
c. Larynx
d. Carina
ANS: A
The slit-shaped space between the true vocal cords forms the glottis. The slit-shaped space between the true vocal cords is not referred to as the epiglottis, the larynx, or the carina.
REF: p. 671
3. The nurse is describing the movement of blood into and out of the capillary beds of the lungs to the body organs and tissues. What term should the nurse use to describe this process?
a. Perfusion
b. Ventilation
c. Diffusion
d. Circulation
ANS: A
Perfusion is the movement of blood into and out of the capillary beds of the lungs to body organs and tissues. Ventilation is the movement of air into and out of the lungs. Diffusion is the movement of gases between air spaces in the lungs and the bloodstream. Circulation is the movement of blood throughout the bloodstream.
REF: p. 671
4. After entering a room of chemical fog, a 20-year-old male cannot stop coughing. Which of the following structures are primarily responsible for his response?
a. Upper respiratory tract mucosa
b. Irritant receptors in the trachea and large airways
c. Irritant receptors in the nostrils
d. Upper respiratory nasal hairs and turbinates
ANS: C
The irritant receptors in the nostrils are responsible for coughing, not those found in the upper respiratory tract mucosa or in the trachea. The cough is not related to stimulation of upper respiratory nasal hairs or the turbinates.
REF: p. 672, Table 26-1
5. One of the functions of the pulmonary system is the:
a. expelling of bacteria.
b. exchange of gases between the environment and blood.
c. movement of blood into and out of the capillaries.
d. principal mechanism for cooling of the heart.
ANS: B
The pulmonary system promotes exchange of gases between the environment and the blood. Neither expelling bacteria, moving blood in and out of the capillaries, nor cooling of the heart is considered a function of the pulmonary system.
REF: p. 671
6. A nurse recalls the pleural membranes are examples of membranes.
a. mucous
b. serous
c. synovial
d. peritoneal
ANS: B
The pleural membranes are serous membranes. Mucous membranes are found in the mouth. Synovial membranes are found in joints. Peritoneal membranes would be found in the bowel.
REF: p. 675
7. A newborn is in respiratory distress and requires ventilation. Tests reveal that he does not produce surfactant due to the absence of:
a. mucus-producing cells.
b. type II alveolar cells.
c. alveolar macrophages.
d. goblet cells.
ANS: B
Surfactant is produced by the type II alveolar cells. Surfactant is not produced by mucus- producing cells, alveolar macrophages, or goblet cells.
REF: p. 672
8. A patient involved in a motor vehicle accident experiences a severe head injury and dies as a result of the loss of respirations. The nurse suspects the area of the brain most likely damaged is the:
a. cerebral cortex.
b. thalamus.
c. basal ganglia.
d. brainstem.
ANS: D
The respiratory center in the brainstem controls respiration by transmitting impulses to the respiratory muscles, causing them to contract and relax. Respirations are not controlled by the cerebral cortex, the thalamus, or the basal ganglia.
REF: p. 676
9. What term is used to describe receptors that respond to increased pulmonary capillary pressure?
a. Irritant receptors
b. Chemoreceptors
c. Stretch receptors
d. J-receptors
ANS: D
J-receptors (juxtapulmonary capillary receptors) are located near the capillaries in the alveolar septa. They are sensitive to increased pulmonary capillary pressure, which stimulates them to initiate rapid, shallow breathing, hypotension, and bradycardia.
Neither irritant receptors, chemoreceptors, nor stretch receptors respond to increased pulmonary capillary pressure.
REF: p. 676
10. The nurse is describing the receptors in the lung that decrease ventilatory rate and volume when stimulated. Which receptors is the nurse discussing?
a. Carbon dioxide receptors
b. Baroreceptors
c. Stretch receptors
d. Chemoreceptors
ANS: C
Stretch receptors, not carbon dioxide receptors, decrease ventilatory rate and volume when stimulated. Baroreceptors regulate blood pressure. Chemoreceptors increase the rate and depth of respiration.
REF: p. 676
11. What nerve provides the lungs with parasympathetic innervation?
a. Vagus
b. Phrenic
c. Brachial
d. Pectoral
ANS: A
Parasympathetic innervations for the lung are via the vagus nerve. Parasympathetic innervations of the lung are not associated with the phrenic, brachial, or pectoral nerves.
REF: p. 676
12. A patient is experiencing respiratory difficulty and retaining too much carbon dioxide. Which receptor sites would be stimulated in an attempt to maintain a normal homeostatic state?
a. Irritant
b. Stretch
c. Peripheral
d. Central
ANS: D
Chemoreceptors monitor arterial blood indirectly by sensing changes in the pH of cerebrospinal fluid (CSF). The central chemoreceptors are sensitive to very small changes in the pH of CSF and can maintain a normal PaCO2. Irritant receptors sense the need to expel unwanted substances. Stretch receptors decrease ventilatory rate and volume when stimulated. The peripheral chemoreceptors become the major stimulus to ventilation when the central chemoreceptors are reset.
REF: p. 677
13. If an individual with respiratory difficulty were retaining too much carbon dioxide, which of the following compensatory responses would the nurse expect to be initiated?
a. Increase in respiratory rate
b. Decrease in ventilation rate
c. Increase in tidal volume
d. Vasodilation of the pulmonary arterioles
ANS: A
To rid the body of excess carbon dioxide, the rate and depth of respiration are increased. A decrease in ventilation rate would increase carbon dioxide. An increase in tidal volume would not decrease carbon dioxide. Vasodilation of the pulmonary arterioles will not rid the body of carbon dioxide.
REF: p. 677
14. During inspiration, muscular contraction of the diaphragm causes air to move into the lung. The mechanism that drives air movement during inspiration results in a(n):
a. decrease in intra-alveolar pressure and shortening of the rib cage.
b. decrease in the size of the thorax and alveolar expansion.
c. increase in the size of the thorax and decrease in intrapleural pressure.
d. increase in atmospheric pressure and intrapleural pressure.
ANS: C
Inspiration occurs due to an increase in the size of the thorax and a decrease in intrapleural pressure, thus creating a negative pressure that draws air into the lungs. The rib cage lengthens, not shortens. The size of the thorax increases, not decreases. Intrapleural pressure decreases, not increases.
REF: p. 678
15. The pressure required to inflate an alveolus is inversely related to:
a. wall thickness.
b. surface tension.
c. minute volume.
d. alveolar radius.
ANS: D
The radius of the alveoli is inversely related to the pressure required to inflate it. The pressure required is not associated with wall thickness, surface tension, or minute volume.
REF: p. 678
16. Surfactant facilitates alveolar distention and ventilation by:
a. decreasing thoracic compliance.
b. attracting water to the alveolar surface.
c. decreasing surface tension in alveoli.
d. increasing diffusion in alveoli.
ANS: C
Surfactant decreases surface tension in alveoli, allowing the lungs to inflate. Surfactant does not decrease thoracic compliance, attract water, or increase diffusion.
REF: p. 678
17. A nurse remembers the majority of total airway resistance occurs in the:
a. bronchi.
b. nose.
c. oral pharynx.
d. diaphragm.
ANS: B
One-half to two-thirds of total airway resistance occurs in the nose, not the bronchi, the oral pharynx, or the diaphragm.
REF: p. 680
18. Which of the following terms should the nurse use when there is a balance between outward recoil of the chest wall and inward recoil of lungs at rest?
a. Functional residual capacity (FRC) is reached.
b. Vital capacity (VC) is reached.
c. Total lung capacity (TLC) is reached.
d. Residual volume (RV) is reached.
ANS: A
Balance between the outward recoil of the chest wall and inward recoil of the lungs occurs at the resting level, the end of expiration, where the FRC is reached. VC is the amount of air that can be forcibly expired after a maximal inspiration. TLC is not reflected by outward and inward recoil. RV is the air that remains trapped in the alveoli.
REF: p. 679
19. While reviewing the results of the pulmonary functions test, the nurse is aware that the maximum amount of gas that can be displaced (expired) from the lung is called:
a. vital capacity (VC).
b. total lung capacity.
c. functional capacity.
d. residual volume.
ANS: A
VC is the amount of air that can be forcibly expired after a maximal inspiration. Total lung capacity is the volume of lung capacity at full inhalation. Functional capacity is not a term used to describe function tests. Residual volume is the amount of air remaining after exhalation.
REF: p. 680, Figure 26-11
20. Under most circumstances, increased work of breathing results in:
a. increased partial pressure of O2 in the lungs.
b. increased oxygen consumption.
c. decreased PaCO2.
d. alterations in alveolar perfusion.
ANS: B
An increase in the work of breathing can result in a marked increase in oxygen consumption. A marked increase in oxygen consumption is not associated with an increase in partial pressure, lower CO2, or altered alveolar perfusion.
REF: p. 680
21. What is the partial pressure of oxygen in the lung given the following conditions? Percentage of oxygen in air: 20
Barometric pressure: 700 mm Hg
a. 111 mm Hg
b. 124 mm Hg
c. 131 mm Hg
d. 140 mm Hg
ANS: D
The partial pressure of oxygen is equal to the percentage of oxygen in the air, 20, times the total pressure (700 mm Hg), or 140 mm Hg (700 0.20 = 140).
REF: p. 681
22. What physiology is present at the base of the lungs?
a. Arterial perfusion pressure is less than that of alveolar gas pressure.
b. Arterial perfusion pressure and alveolar gas pressure are less than they are at the apex.
c. Arterial perfusion pressure exceeds alveolar gas pressure.
d. Arterial perfusion and alveolar gas pressure are equal.
ANS: C
In the base of the lungs, both arterial and venous pressures are greater than alveolar pressure, and blood flow is not affected by alveolar pressure. It is in the apex that alveolar pressure exceeds pulmonary arterial and venous pressures. In zone II, also part of the apex, alveolar pressure is greater than venous pressure, but not arterial pressure.
REF: pp. 681-682
23. While auscultating a patient’s lungs, a nurse recalls the alveoli in the apices of the lungs are
than alveoli in the bases.
a. larger
b. more numerous
c. more compliant
d. less perfused
ANS: A
The alveoli in the upper portions, or apices, of the lungs contain a greater residual volume of gas and are larger and less numerous, not more numerous, than those in the lower portions. The apices are less compliant but better perfused.
REF: p. 681
24. A patient asks how oxygen is transported in the body. The nurse’s best response is that most oxygen (O2) is transported:
a. dissolved in the plasma.
b. bound to hemoglobin.
c. in the form of carbon dioxide (CO2).
d. as a free-floating molecule.
ANS: B
Most O2 is transported bound to hemoglobin, not as a free-floating molecule; only a small amount is dissolved in plasma. O2 is not transported in the form of CO2. O2 is transported bound to hemoglobin.
REF: p. 682
25. Diffusion of respiratory gases takes place at the:
a. alveolocapillary membrane.
b. visceral pleurae.
c. parietal pleurae.
d. respiratory center.
ANS: A
Diffusion of respiratory gases takes place across the alveolocapillary membrane. The visceral and parietal pleurae are the linings of the lung; gas exchange does not occur here. The respiratory center is where impulses to the respiratory muscles are generated.
REF: p. 682
26. In a patient with acidosis, the nurse would expect the oxyhemoglobin dissociation curve to shift:
a. to the right, causing more O2 to be released to the cells.
b. to the left, allowing less O2 to be released to the cells.
c. downward, allowing less O2 to dissolve in the plasma.
d. upward, allowing more O2 to dissolve in the plasma.
ANS: A
The oxyhemoglobin dissociation curve is shifted to the right, not the left, by acidosis (low pH) and hypercapnia (increased PaCO2); more, not less, O2 is released to cells. The oxyhemoglobin dissociation curve is not downward or upward, by acidosis.
REF: p. 683
27. Carbon dioxide (CO2) is mainly transported in the blood:
a. attached to oxygen (O2).
b. dissolved in red blood cells.
c. combined with albumin.
d. in the form of bicarbonate.
ANS: D
CO2 is carried in the blood as bicarbonate and not attached to O2, dissolved in red blood cells, or combined with albumin.
REF: p. 684
28. Pulmonary function tests reveal that an 80-year-old dyspneic patient has an increase in residual volume. A nurse suspects the most likely cause of the increased residual volume is
in lung compliance.
a. an increase
b. a decrease
c. no change
d. an absence
ANS: A
The patient is experiencing an increase in lung compliance. Increased compliance indicates that the lungs or chest wall is abnormally easy to inflate and has lost some elastic recoil.
Decreased compliance is seen in acute breathing disorders.
REF: p. 684, Geriatric Considerations
MULTIPLE RESPONSE
1. Which structures may be found in the walls of the respiratory bronchi? (select all that apply)
a. Smooth muscle
b. Surfactant-producing glands
c. Goblet cells
d. Ciliated cells
e. Epithelial lining
ANS: A, C, D, E
The bronchial walls have three layers: an epithelial lining, a smooth muscle layer, and a connective tissue layer. The epithelial lining of the bronchi contains single-celled exocrine glands—the mucus-secreting goblet cells—and ciliated cells. Surfactant-producing glands are found in the alveoli.
REF: pp. 671-672
COMPLETION
1. seconds is required for oxygen (O2) concentration to equilibrate (equalize) across the alveolocapillary membrane.
ANS: 0.25
REF: p. 682
2. % of oxygen (O2) enters the bloodstream bound to hemoglobin.
ANS: 97
REF: p. 683
3. At sea level, the partial pressure of oxygen is approximately % (round to the nearest whole number).
ANS:
21
At sea level, the air is made up of oxygen (20.9%).
REF: p. 681 [Show Less]