chapter 26: Gas Exchange

The 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.

humidify air

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

Glottis

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

Perfusion

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

irritant receptors in the nostril

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.

exchange of gases between the environment and blood

3.     A nurse recalls the pleural membranes are examples of _____ membranes.

a.      mucous

b.     serous

c. synovial

d.  peritoneal           

 

serous

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.

type II alveolar cells

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.

brainstem

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

J - receptors

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

stretch receptors

What nerve provides the lungs with parasympathetic innervation?

a.      Vagus

b.     Phrenic

c.      Brachial

d.     Pectoral

vagus

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

central

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

increase in respiratory rate

  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.

increase in the size of the thorax and decrease in intrapleural pressure

The pressure required to inflate an alveolus is inversely related to:

a.      wall thickness.

b.     surface tension.

c.      minute volume.

d.     alveolar radius.

alveolar radius

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.

decreasing surface tension in alveoli

A nurse remembers the majority of total airway resistance occurs in the: a. bronchi.

b.     nose.

c.      oral pharynx.

d.     diaphragm.

nose

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.

functional residual capacity (FRC) is reached

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.

vital capacity (VC)

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.

increased oxygen consumption

18.     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

140mmHg

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

arterial perfusion pressure exceeds alveolar gas exchange

18.     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

larger

  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.

bound to hemoglobin

25.     Diffusion of respiratory gases takes place at the:

a.      alveolocapillary membrane.

b.     visceral pleurae.

c.      parietal pleurae.

d.     respiratory center.

alveolocapillary membrane

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.

to the right, causing more O2 to be released to the cells

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.

in the form of bicarbonate

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

an increase

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

A, C, D, E

1.     _____ seconds is required for oxygen (O₂) concentration to equilibrate (equalize) across the alveolocapillary membrane.

0.25

  ____% of oxygen (O₂) enters the bloodstream bound to hemoglobin.

97%

1.     At sea level, the partial pressure of oxygen is approximately ___% (round to the nearest whole number).

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