Deck 17: Pulmonary Anatomy and Physiology

Question 1

The oxygen saturation of a healthy individual rarely reaches 100% on room air.This can best be explained by which of the following concepts?

A) Physiologic shunting
B) Alveolar capillary diffusion
C) Collateral air passages
D) Anatomic dead space

Answer 1

Physiologic shunting

Question 2

Patients who have aspiration pneumonia present with right lower lobe involvement more often than with involvement of the left lower lobe.You know this is because

A) the left mainstem bronchus angles down more than the right.
B) more people are right-side dominant.
C) the right mainstem bronchus angles down more than the left.
D) the right mainstem bronchus is narrower than the left.

Answer 2

the right mainstem bronchus angles down more than the left.

Question 3

Which of the following statements describes the left bronchus?

A) The left bronchus has a slight angle of 20 to 30 degrees from the midline.
B) The two mainstem bronchi are structurally and functionally similar.
C) The left bronchus is slightly narrower.
D) The bronchi are the end units of the bronchial tree.

Answer 3

The left bronchus is slightly narrower.

Question 4

Normally,the central chemoreceptors responsible for triggering ventilation changes respond to which of the following?

A) Increased PaCO?
B) Increased HCO?-
C) Decreased PaO?
D) Increased PaO?

Question 5

A shift to the left of the oxyhemoglobin dissociation curve would cause which of the following?

A) Better tissue perfusion
B) Lower SpO?
C) Decreased hemoglobin affinity for O?
D) Impaired tissue oxygen delivery

Question 6

The conducting airways

A) participate in gas exchange.
B) cool the incoming airway.
C) remove moisture from incoming air.
D) prevent the entry of foreign material.

Question 7

COPD produces increased work of breathing by which of the following mechanisms?

A) Decreased lung compliance
B) Decreased chest wall compliance
C) Increased atelectasis
D) Increased airway resistance

Question 8

Which of the following ranges would be considered normal pulmonary artery systolic pressures?

A) 15 to 30 mm Hg
B) 4 to 12 mm Hg
C) 25 to 35 mm Hg
D) 1 to 11 mm Hg

Question 9

Which of the following is considered physiologic dead space?

A) Respiratory bronchiole and unperfused alveoli
B) Trachea and perfused alveoli
C) Trachea and unperfused alveoli
D) Trachea and mainstem bronchi

Question 10

The trachea divides into the right and left mainstem bronchi at what point?

A) Posterior larynx
B) Cricoid cartilage
C) Epiglottis
D) Major carina

Question 11

A patient has sustained a stroke.The speech therapist tells you that the patient cannot control his epiglottis.You know that this patient

A) is at increased risk of aspiration.
B) will need surgery to close his epiglottis.
C) will need a tracheostomy to breathe.
D) is at risk for a pneumothorax.

Question 12

Which of the following V/Q ratios would most suggest intrapulmonary shunting?

A) 0.8
B) 2.2
C) 0.4
D) V/Q ratios are not related to shunting.

Question 13

Which of the following arteries has the lowest oxygen concentration?

A) Aorta
B) Subclavian
C) Carotid
D) Pulmonary

Question 14

If a patient sustained an injury to the apneustic center in the lower pons area,in which of the following areas would you most expect the patient to exhibit problems?

A) Respiratory rate
B) Triggering exhalation
C) Respiratory rhythm
D) Depth of respiration

Question 15

Lack of surfactant can cause which of the following conditions?

A) Pulmonary embolus
B) Pulmonary hypertension
C) Pulmonary atelectasis
D) Pulmonary edema

Question 16

The primary functions of the pulmonary system are

A) gas exchange and the movement of air in and out of the lungs.
B) gas exchange and the transfer of oxygen to the tissues.
C) the movement of blood in and out of the lungs and the removal of body waste products.
D) gas exchange and the prevention of infections.

Question 17

Which of the following is a passive event in a spontaneously breathing patient?

A) Coughing
B) Inhalation
C) Exhalation
D) Yawning

Question 18

Alveolar type II cells secrete which of the following lipoproteins?

A) Trypsin
B) Chyme
C) Amylase
D) Surfactant

Question 19

You would expect a patient in diabetic ketoacidosis to exhibit which of the following?

A) Breathe faster to increase pH
B) Breathe slower to increase pH
C) Breathe faster to decrease pH
D) Breathe slower to decrease pH

Question 20

Most of the work of breathing is done by the

A) pleura.
B) intercostal muscles.
C) diaphragm.
D) sternocleidomastoid.

Question 21

Methemoglobin causes difficulty with oxygenation because

A) methemoglobin does not carry oxygen as normal hemoglobin would.
B) carbon monoxide has a greater affinity for the hemoglobin than oxygen.
C) only 80% of the total oxygen is carried on the hemoglobin.
D) the anemia causes decreased numbers of hemoglobin receptor sites.

Question 22

The central chemoreceptors are stimulated by

A) decreased PaO?.
B) increased PaO?.
C) decreased SaO?.
D) increased PaCO?.

Question 23

How much of the basal oxygen consumption is required by the pulmonary system during normal quiet breathing?

A) 10% to 20%
B) 5% to 10%
C) 3% to 5%
D) 1% to 2%

Question 24

Based on the oxyhemoglobin dissociation curve,respiratory acidosis will have which effect?

A) A shifting of the curve to the left
B) Increased oxygen saturation
C) Enhanced oxygen delivery at the tissue level
D) Hypothermia

Question 25

The lobes are divided into 18 segments.How many are on the right lung?

A) 3
B) 8
C) 10
D) 15

Question 26

Muscles of exhalation include which of the following?

A) Abdominal
B) Diaphragm
C) External intercostals
D) Internal intercostals
E) Scalene

Question 27

Which of the following factors will increase diffusion of gases across the alveolar capillary membrane?

A) A decrease in surface area of the membrane
B) An increase in thickness of the membrane
C) An increase in the driving pressure of the gas
D) A decrease in the solubility coefficient of the gas

Question 28

Which of the following factors will result in a shift of the oxyhemoglobin dissociation curve to the left?

A) Increased PaCO?
B) Increased pH
C) Increased temperature
D) Increased 2,3-DPG

Question 29

A patient is admitted to the critical care unit with an acute exacerbation of chronic emphysema.Respirations are 28 breaths/min.A pulmonary artery catheter is in place.Pulmonary artery systolic (PAS)is 38 mm Hg with a pulmonary artery mean (PAM)of 22 mm Hg.Blood gases reveal an uncompensated respiratory acidosis.The patient's work effort for breathing is increased related to the effect of emphysema,which is

A) increased lung compliance.
B) decreased lung recoil.
C) increased chest wall compliance.
D) widespread atelectasis.

Question 30

Trauma to which vertebrae will cause ventilation dysfunction?

A) C3-C5
B) C5-T?
C) T? -T6
D) T7-T10

Question 31

Under normal situations,the normal ventilation to perfusion ratio is 4:5 (0.8).Atelectasis can cause a shunt-producing ventilation/perfusion mismatch.This occurs primarily as a result of

A) perfusion exceeding ventilation.
B) ventilation exceeding perfusion.
C) an alveolus that is receiving ventilation but not perfusion.
D) an alveolus that is receiving perfusion but not ventilation.

Question 32

The lymphatic system plays which of the following important roles?

A) Ridding lung tissue of excess CO?
B) Connecting the thebesian veins to the coronary circulation
C) Removing fluid from the lungs
D) Producing immune responses
E) Removing cell debris from the lungs

Question 33

The most important function of type I alveolar epithelial cells is

A) that they comprise 90% of total alveolar surface in the lungs for gas exchange.
B) the ability to produce, store, and secrete pulmonary surfactant.
C) the ability to trap foreign particles for autodigestion.
D) the maintenance, repair, and restoration of the mucociliary escalator.

Question 34

The portion of total ventilation that participates in gas exchange is known as

A) alveolar dead space.
B) anatomic dead space.
C) physiologic dead space.
D) alveolar ventilation.

Question 35

Which nerve stimulates movement of the diaphragm?

A) Musculocutaneous nerve
B) Phrenic nerve
C) Median nerve
D) Axillary nerve

Question 36

Which pleura adheres to the lungs?

A) Parietal
B) Visceral
C) Intrapleural
D) Surfactant

Question 37

Oxygen saturation of left atrial blood is normally between 96% and 99%.What is the explanation for less than 100% saturation?

A) As blood passes to the alveolar-capillary membrane, a predicted percentage of hemoglobin will not bind with oxygen.
B) During normal respiration, the majority of alveoli are not expanded.
C) Venous blood from the bronchial circulation is returned to the left atrium.
D) A small amount of blood leaks from the right atrium to the left atrium with each ventricular contraction.

Question 38

The movement of air into and out of the lungs is termed

A) ventilation.
B) respiration.
C) diffusion.
D) perfusion.

Question 39

Which of the following statements describes the relationship between the pulmonary circulation and the pulmonary vascular bed?

A) The pulmonary circulation is a high-pressure system with normal pressures averaging 100/60 to 120/70 mm Hg.
B) Because of the low pulmonary arterial pressures, the right ventricular wall thickness needs to be only one-third that of the left ventricle.
C) Pulmonary hypertension is defined as increased pulmonary artery systolic pressure above 20 mm Hg.
D) The most common cause of pulmonary hypertension is right-sided heart failure.

Question 40

A patient is admitted to the critical care unit with an acute exacerbation of chronic emphysema.Respirations are 28 breaths/min.A pulmonary artery catheter is in place.Pulmonary artery systolic (PAS)is 38 mm Hg with a pulmonary artery mean (PAM)of 22 mm Hg.Blood gases reveal an uncompensated respiratory acidosis.Based on the readings obtained from the pulmonary artery catheter,the patient shows evidence of which of the following?

A) Physiologic shunting
B) Widespread atelectasis
C) Pulmonary hypertension
D) Ventilation/perfusion mismatch