UNIT 8
Alterations in Respiratory
Function
Originally developed by:
Marlene Reimer RN, PhD, CCN(C)
Associate Professor
Faculty of Nursing, University of Calgary
&
Associate in Nursing, Calgary Health Region
Revised (2000) by:
Karen Then RN, PhD
Associate Professor
Faculty of Nursing, University of Calgary
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Unit 8 Table of Contents
Overview .......................................................................................................................4
Aim ............................................................................................................................. 4
Objectives .................................................................................................................. 4
Resources ................................................................................................................... 4
Orientation to the Unit ............................................................................................ 5
Web Links.................................................................................................................. 5
Section 1: Alterations in Respiratory Function ......................................................6
Review of Normal Ventilation and Respiration .................................................. 6
Clinical Manifestations of Pulmonary Alterations .............................................. 6
Learning Activity #1—Quiz ................................................................................... 6
Obstructive and Restrictive Pulmonary Disease ................................................. 7
Learning Activity #2—Case Study: A Patient with COPD .............................. 13
References ...................................................................................................................20
Glossary .......................................................................................................................21
Acronym List ...............................................................................................................22
Answers to Learning Activities ...............................................................................23
Learning Activity # 1—Quiz ................................................................................ 23
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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UNIT 8
Alterations in Respiratory Function
As in other units you will find that a good understanding of normal structure
and function will be helpful as you build your knowledge base regarding
alterations in function and system failure. That is why the first activities
involve review of the anatomy and physiology of the respiratory system.
Rather quickly you will realize that “respiratory system” is a bit of a
misnomer as respiration technically refers to the actual exchange of oxygen
and carbon dioxide, whereas ventilation refers to the act of breathing.
As you go through this unit you will find yourself drawing on knowledge
from the unit on: Alterations in Fluid and Electrolytes especially with
relation to blood gases. In the case study at the end of this unit you will have
some opportunities to test your application of that knowledge.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
Overview
Aim
The emphasis in this unit is on acquiring a basic understanding of obstructive
and restrictive pulmonary disease. To a lesser extent you will be assisted to
examine developmental differences in vulnerability to alterations in
respiratory function and the consequences of respiratory failure.
Objectives
On completion of this unit you should be able to:
1. Differentiate between obstructive and restrictive respiratory diseases.
2. Describe the etiology, pathophysiology and clinical manifestations of
obstructive and restrictive diseases.
3. Describe the management of chronic obstructive pulmonary disease.
4. Describe the etiology and clinical manifestations of respiratory failure.
5. Compare alteration of pulmonary function in children with adults in
relation to effects of structural differences and types of conditions.
Resources
Requirements
Print Companion: Alterations in Respiratory Function
Most of the information that you require for this unit will come from Porth
(7th ed.) Chapters 29 and 31. You should also plan to access a current
pharmacology textbook.
Supplemental Reading
If you are interested in more information on any of the topics in this unit,
check out the following references:
Brandstetter, R. (1986). The adult respiratory distress syndrome -1986. Heart and Lung, 15(2), 155-163.
Burrows, B. (1990). Differential diagnosis of chronic obstructive
pulmonary disease. Chest (supplemental), 97(2), 165-185.
Carroll, P. (1986, July). What you can learn from pulmonary function
tests. RN, 24-27.
Gross, N.J. (1990). Chronic obstructive pulmonary disease: current
concepts and therapeutic approaches. Chest (supplemental), 97(2), 195 – 235.
Hahn, K. (1987). Slow-teaching the C.O.P.D. patient. Nursing 87, 17(4),
34-42.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Konishi, M., Fujiwara, T., Naito, T., Takeuchi, U., Ogawa, Y., Inukai,
K., Fujimura, M., Nakamura, H., & Hashimoto, T. (1988). Surfactant
replacement therapy in neonatal respiratory distress syndrome. European
Journal of Pediatrics, 147, 20-25.
Owen, C.L. (1999). New directions in asthma management. AJN, 99(3),
26-33.
Stobart, M.J. (1999). Prevention and management of COPD.
Professional Nurse, 14(4), 241-244.
Orientation to the Unit
Before you get started on the serious work of the unit try the following
exercise:
Take a piece of paper and draw 3 columns on it. Now in the centre column
list all of the diseases and conditions of the respiratory system that you can
think of.
In the first column list the etiology and risk factors for conditions and
diseases of the respiratory system. (Don’t worry about matches initially
although looking at the centre column may help you think of different ones.)
Now draw lines matching up the first and second columns to the best of your
knowledge.
What things from your first column seem to be the most common risk
factors?
If your list was like mine you probably found that environmental irritants
such as smoking and allergens linked with many of the respiratory
conditions. Did you also consider infectious agents? trauma? developmental
differences? conditions originating in other body systems (e.g.,
cardiovascular) which then impact the respiratory system?
The last column can be labelled pathogenesis. As you recall, pathogenesis
refers to the development or evolution of the disease, for example, what does
the pneumococcus actually do that results in the disease that we know as
pneumonia? In this unit we certainly will not be able to address all of the
conditions you listed in the centre column. However you will find that the
basic mechanisms are not that varied (e.g., inflammation, obstruction) so that
you should gradually be able to fill in most of the third column as you work
through the unit.
Web Links
All web links in this unit can be accessed through the Web CT system.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
Section 1: Alterations in Respiratory Function
Review of Normal Ventilation and Respiration

Skim Chapter 29 : Control of Respiratory Function in Porth (7th ed).
Clinical Manifestations of Pulmonary Alterations
Answer the following questions to reinforce your understanding of key
points (see the end of this unit if you are unsure of the answers).
Learning Activity #1—Quiz
1. Dyspnea is usually a manifestation of ____________ (localized,
diffuse) pulmonary disease whereas haemoptysis indicates a
_______________ (localized, diffuse) abnormality.
2. Cyanosis is a reliable indicator of hypoxemia (true or false). In which
patient would cyanosis be a more serious sign: a 50-year-old man
with chronic bronchitis or a 29-year-old woman with postpartum
haemorrhage?
3. The differences between hypoxemia and hypoxia are
4. Ventilation is _______________________________.
5. Respiration is _______________________________.
6. Low ventilation/perfusion ratio (V/Q) describes the state of
_________________ (good, poor) ventilation of a _______________
(well perfused, poorly perfused) segment of the lung. An example of a
condition which it is seen is _____________.
7. High V/Q describes the state of _______________ (good, poor)
ventilation of a____________________ (well perfused, poorly
perfused) segment of the lung. An example of a condition where it is seen
is ____________________.
8. Administration of high levels of oxygen is not effective in adult
respiratory distress syndrome and respiratory distress syndrome of
the newborn because
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Obstructive and Restrictive Pulmonary Disease –
Porth, Chapter 31.
One way to simplify comprehension of the disorders of ventilation is to
classify them as obstructed breathing or restricted breathing.
Obstructive pulmonary disease, as the name implies, refers to conditions
that affect the movement of air in and out of the lungs. The most common
obstructive lung diseases in adults are chronic bronchitis, emphysema, and
asthma. Each disease has some distinct features (as outlined in Table 8.1) but
they often coexist to varying degrees in the same individual so together are
called chronic obstructive pulmonary disease (COPD). The pulmonary effects
of cystic fibrosis can also be classified as obstructive. All of the obstructive
pulmonary diseases are characterized by:



reduced vital capacity
difficult expiration
increased residual capacity (see Figure 8.1)
Restricted breathing results from conditions in which the lungs or chest wall
are stiffened and compliance is reduced. Examples of restrictive pulmonary
disease include:
Condition
pulmonary fibrosis
Mechanism
"stiff lungs” from scar tissue and
loss of compliance
adult respiratory distress
syndrome (ARDS)
“stiff lungs” from inactivated
surfactant and progressive fibrosis
respiratory distress syndrome of
the newborn (RDS)
“stiff lungs” from insufficient
surfactant and atelectasis
kyphoscoliosis
stiff or distorted chest wall
neuromuscular diseases
impaired respiratory muscle
function
All of the restrictive pulmonary diseases are characterized by reduced vital
and residual capacity (see Figure 8.1).
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
Figure 8.1 Comparison of Vital and Residual capacity in three situations
Note:
Vital Capacity (VC) is: the largest volume of air that may be forcefully
expired (after a maximum inspiration).
Residual Volume (RV) is: the amount or volume of air that remains in
the lungs following a maximum expiration.
See glossary at the end of this unit for more definitions.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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A chart summarizing the changes in selected restrictive, obstructive and
pulmonary vascular conditions can be found in Table 8.1. You will probably
want to add your own notes to the chart to further enhance your
understanding.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
Table 8.1 Disorders of Ventilation and Respiration
Type of Condition
Etiology
Pathogenesis
Restrictive
Interstitial Lung
Disease

inhaled agents (e.g. asbestos), silicosis
 inflammation initially phagocytes?
then fibroblasts take over

ARDS (Shock
Lung)

any major body disorder, i.e.,
“catastrophic event”

Newborn RDS
(Hyaline
membrane disease)
Obstructive
Emphysema

immaturity -- not mature enough to
produce surfactant


smoking   antibacterial activity of
alveolar macrophages (normally part
of surfactant film) 
deficiency of alpha/anti-trypsin
(McCance & Heuther, 1994, pp. 11691172
1. lose septa between alveolar sacs
become floppy  rupture, overinflate, collapse, air trapping
2. 2. as septa  the bed of capillaries 
(because walls of septa full of
capillaries  right heart failure  cor
pulmonale)
 inflammation of the tracheo-bronchial
tree   number of goblet cells,
producing an excessive amount of
mucus,  thickening,  hypersecretion,  in diameter in small
airways
 disease of airways immunological
component. Mast cells and other
inflammatory cells release mediators
 swelling
 reflex component - inhaled antigen
sets of protective response 
bronchoconstriction & inflammation
 bronchiolar obstruction with thick
mucus, hyperplasia of goblet cells 
bronchitis, etc.
 regional - part of the lungs and
embolus occludes a portion of
pulmonary circulation
 general - dissemination throughout
lung field
 pulmonary hypertension


Bronchitis


smoking and other inhaled irritants 
 hyperplasia goblet cells
 in ciliated cells
 mucociliary escalator
Asthma
Obstructive but
some unique
features

Cystic Fibrosis

genetic

mainly secondary to other problems,
e.g., immobility  deep vein
thrombosis  pulmonary embolus
trauma - # long bones  fat emboli
Pulmonary
Vascular
Pulmonary
embolus
Fat emboli

hypersensitivity of the bronchial walls
and spasms of muscles surrounding
bronchi
intrinsic vs. extrinsic (allergen) or
mixed
lay down abnormal amounts of fibrin
collagen coating the outside of the
alveoli making them stiff “stiff
lung”
 permeability of capilliary membrane
pulmonary edema & inactivation of
surfactant  “stiff lung”
atelectasis, weak chest wall and lack
of surfactant  “stiff lung”
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Other conditions and effects:
Pneumonia
 may have  PO2 and  PCO2
 infection in lungs interferes more with oxygen exchange than with
CO2 exchange  hypoxia hyperventilation in an attempt to
compensate
Respiratory Depression (e.g. due to general anaesthesia)
 PO2 cannot stimulate respiration so PCO2 rises respiratory
acidosis
Tuberculosis
 microorganisms get lodged in lung and cause nonspecific
pneumonitis
 collagenous scar tissue forms
 common clinical manifestations include fatigue, night sweats, weight
loss, low-grade fever, cough and purulent sputum
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
Figure 8.2 Volumes with Normal Inspiration and Expiration, Maximum
Inspiration, and Maximum Expiration in Three Situations
Figure 8.3 Forced Expiratory Volume in Three Situations
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Your emphasis in this section should be on comprehension of the definition
and essential mechanism(s) involved in each condition described. It is not
necessary to try to memorize the details of clinical manifestations or
treatments as comprehension of the basic mechanisms should make the rest
fairly easy to predict. You may find it helpful to add to the previous chart
and/or develop a table of definitions to summarize this segment of your
reading.
Now that you have worked through the chart and the readings you are ready
to apply your knowledge in a case study. To do the case study you will need
to access a pharmacology textbook. You may want to have your notes from
the unit on: Alterations in Fluids and Electrolytes handy.
Equally important however is the confidence to try to figure out the answers
for yourself. It is not intended that you spend hours looking them up in
assorted references. In fact you might not find all the answers in the depth
you would like even if you did look for them. Our understanding is limited
(even at the beginning of the 21st Century!) and sometimes treatments are
used because we know they work, not because we understand exactly how
they work. Likewise we cannot always explain some of the clinical
manifestations that, from experience, we know typically occur.
Learning Activity #2—Case Study: A Patient with
COPD
(Adapted from Unit IV: A Patient with COPD, Pulmonary System Series,
Clinical Simulations for Critical Care Nurses, a computer assisted
instructional program produced by the American Association of Critical Care
Nurses and Medi-Sim.)
Context
You are a nurse working in an 8-bed Intensive Care Unit on the day shift.
You are assigned to Mr. Smith, a 69-year-old white male with chronic
obstructive lung disease (COPD) who has just been transferred from the
Emergency Department in respiratory distress.
Admission Data
Jim Smith, a retired telephone lineman, has been treated over the past 10 days
by his family physician for flu-like symptoms of fever, pulmonary congestion
and cough productive of green purulent sputum. He became quite dyspneic
this morning.
Mr. Smith has had COPD for the past 15 years with progressive dyspnea,
fatigue and activity intolerance. He has no known allergies or environmental
exposure to irritants. He has smoked 2 packs/day for the past 50 years. He
has a long history of recurrent pulmonary infections.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
1. Vital signs and blood gases on admission at 0800 were as indicated in
the chart below. Briefly explain the mechanism(s) contributing to each
value that is abnormal.
Measurement/Lab
Value
Mechanism(s) Contributing to Abnormal Values
Temp 38.6° C
Pulse 104
Resp 30
BP 143/86 mmHg
Blood gases
PO2 60
pH 7.35
pCO2 57
HCO3 31
O2 Sat 89%
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
2. Explain the rationale for treatment initiated in the Emergency
Department:
Ventolin
nebulizer/Ventolin
infusion
O2 @ 2 1itres per nasal
cannulae
Steroid infusion
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
3. As the nurse admitting him to ICU your initial assessment includes
the following findings. Briefly discuss the significance and
mechanisms accounting for each.
Assessment
Significance/mechanisms
Dusky, wide-eyed, restless,
diaphoretic, fatigued
Respirations irregular, noisy,
laboured
Nailbeds slightly cyanosed, clubbing
of digits
Barrel-chested
Lung sounds –- fine crackles
posteriorly, diminished breath
sounds throughout, scattered
rhonchi anteriorly
Heart sounds distant with S3 at the
apex
Jugular veins distended, enlarged
liver
Presence of increased fremitus to the
midline of the posterior chest on
palpation of the thorax
Hyperresonance in all lung fields
with dullness and bronchial breath
sounds elicited at the bases on
percussion posteriorly
Pale and dusky at times with central
cyanosis seen on the undersurface of
the tongue
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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4. What risk factor(s) for COPD are evident in Mr. Smith’s history? What
is thought to be the mechanism(s) by which the risk factor(s)
contribute to obstructive lung disease?
5. Initial management for Mr. Smith is outlined below. Indicate the
rationale for each intervention in the chart below.
Intervention
Rationale
Prescribed Medical Tx
Steroids
Antibiotics
Bronchodilators
Continuous 02 therapy
Chest physiotherapy
Nursing Tx
Encourage Diaphragmatic
breathing
Surveillance of vital signs,
breath sounds & neuro
status
Monitor ECG rhythm
Position in High Fowler’s
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
6. At this point in his hospitalization what would be the most
appropriate goal regarding his total fluid intake? Why?
a. 1000-2000 ml/day
b. 2000-3000 ml/day
c. 3000-4000 ml/day
7. At 1230 Mr. Smith’s ABG’s are as follows:
PO2 35 pH 7.28 pCO2 65 HCO3 29 O2 Sat 70% (on 2L of O2)
Which of the following terms is the most accurate interpretation of
these results?
a. severe uncompensated respiratory acidosis
b. severe compensated respiratory acidosis
c. severe uncompensated respiratory alkalosis
Mr. Smith is intubated and placed on a ventilator. He is discharged from
hospital after 10 days in ICU and 3 days on a medical unit. The remaining
questions apply to the long-term management of his condition.
8. He is given instruction on pursed lip breathing prior to his discharge.
Explain why this method is effective for COPD patients.
9. Mr. Smith has been unable to sleep for more than 2-3 hours at a time.
Why is such sleep pattern disturbance common with COPD patients?
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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10. Mr. Smith is 190 cm tall and weighs 68 kg suggesting nutritional
deficiency. Discuss the possible physiological bases for this deficiency
and its significance with his condition.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
References
Brandstetter, R. (1986). The adult respiratory distress syndrome -1986. Heart and Lung, 15(2), 155-163.
Burrows, B. (1990). Differential diagnosis of chronic obstructive
pulmonary disease. Chest (supplemental), 97 (2), 165-185.
Carroll, P. (1986). What you can learn from pulmonary function tests.
RN, 24-27.
Gross, N.J. (1990). Chronic obstructive pulmonary disease: current
concepts and therapeutic approaches. Chest (supplemental), 97 (2), 195 – 235.
Hahn, K. (1987). Slow-teaching the C.O.P.D. patient. Nursing 87, 17(4),
34-42.
Kersten, L.D. (1989). Comprehensive respiratory nursing: A decisionmaking approach. Philadelphia: Saunders.
Konishi, M., Fujiwara, T., Naito, T., Takeuchi, U., Ogawa, Y., Inukai,
K., Fujimura, M., Nakamura, H., & Hashimoto, T. (1988). Surfactant
replacement therapy in neonatal respiratory distress syndrome. European
Journal of Pediatrics, 147, 20-25.
Mahler, D., Rosiello, R., & Loke, J. (1986). The aging lung. Geriatric
Clinics of North America, 2(2), 215-225.
Porth, C. M. (2005). Pathophysiology-Concepts of Altered Health
States (7th ed). Philadelphia: Lippincott.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Glossary
apnea: Temporary cessation of breathing.
compliance: A measure of how easily a tissue is stretched. With respect to
lung tissue it refers to the quality of yielding to pressure.
dyspnea: A subjective sensation of difficulty breathing.
elasticity: The ability of lung tissue to return to normal resting position and
shape. It is the reciprocal of compliance.
elastance: The elastic forces of lung tissue that prevent over expansion or
over distention of the thorax.
expiratory reserve volume (ERV): The maximum volume of air that can be
expired forcibly following a normal expiration.
forced expiratory volume (FEV): The maximum volume of air forcefully
expired (after a maximum inspiration) in one second.
functional residual capacity (FRC): At the completion of a normal expiration
FRC represents the volume of air remaining in the lungs.
hypoxia: Refers to a reduction in tissue or cell oxygenation.
inspiratory capacity (IC): The maximum volume of air that can be breathed
in after a normal breath out.
obstructive pulmonary disease: Refers to those conditions that affect the
movement of air in and out of the lungs (e.g.,, chronic bronchitis,
emphysema, asthma).
residual volume (RV): The amount or volume of air that remains in the lungs
following a maximum expiration.
respiration: Strictly speaking, respiration refers to the gaseous exchange of
oxygen and carbon dioxide in the cells of the body.
restrictive pulmonary disease: Conditions in which the lungs or chest wall
are stiffened and compliance is decreased (e.g., pulmonary fibrosis, ARDS,
atelectasis, pulmonary edema).
tachypnea: Rapid respiratory rate above the normal for the individual.
tidal volume (VT): Refers to the total volume of air inhaled and exhaled with
each normal breath.
total lung capacity (TLC): The greatest volume of air that can be held in the
lungs following a maximum inspiration.
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
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Unit 8 Alterations in Respiratory Function
ventilation: Refers to the movement of air into and out of the lungs.
vital capacity (VC): The largest volume of air that may be forcefully expired
(after a maximum inspiration).
Acronym List
ARDS Adult Respiratory Distress Syndrome
CF
Cystic Fibrosis
COPD Chronic Obstructive Pulmonary Disease
ERV
Expiratory Reserve Volume
FEV
Forced Expiratory Volume
FRC
Functional Residual Capacity
IC
Inspiratory Capacity
PCO2 Partial pressure of Carbon Dioxide
PO2
Partial pressure of Oxygen
RC
Residual Capacity
RV
Residual Volume
TLC
Total Lung Capacity
V/Q
Ventilation-perfusion ration
VT
Tidal Volume
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary
Unit 8 Alterations in Respiratory Function
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Answers to Learning Activities
Learning Activity # 1—Quiz
Common Clinical Manifestations of Pulmonary Alterations. The correct
answers are underlined.
1. Dyspnea is usually a manifestation of diffuse pulmonary disease
whereas haemoptysis indicates a localized abnormality.
2. Cyanosis is a reliable indicator of hypoxemia (false). In which patient
would cyanosis be a more serious sign: a 50-year-old man with
chronic bronchitis or a 29-year-old woman with postpartum
haemorrhage? (Persons with chronic bronchitis often have a higher
haemoglobin as compensation for the chronic hypoventilation
whereas the young mother probably had a low to normal
haemoglobin prior to the haemorrhage and now has even less so that
by the time she becomes cyanotic her oxygenation is quite poor.)
3. The differences between hypoxemia and hypoxia are that hypoxemia
refers specifically to reduced oxygenation of arterial blood caused by
respiratory alterations whereas hypoxia is reduced oxygenation to
cells anywhere in the body and may be caused by alterations in other
systems.
4. Ventilation is “the mechanical movement of . . . air into and out of the
lungs”
5. Respiration is “the exchange of oxygen and carbon dioxide during
cellular metabolism”
6. Low ventilation/perfusion ratio (V/Q) describes the state of poor
ventilation of a well perfused segment of the lung. An example of a
condition which it is seen is bronchitis, asthma
7. High V/Q describes the state of good ventilation of a poorly perfused
segment of the lung. An example of a condition where it is seen is
pulmonary embolism
8. Administration of high levels of oxygen is not effective in adult
respiratory distress syndrome and respiratory distress syndrome of
the newborn because pulmonary shunting is occurring such that a
significant portion of the pulmonary capillary blood passes through
physiologic dead space in which the alveoli are so obstructed,
collapsed or filled with fluid that no diffusion of O2 occurs
Rankin, Reimer & Then. © 2000 revised edition. NURS 461 Pathophysiology, University of Calgary