Indications for PFT

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Transcript Indications for PFT

Indications for PFT
RET 2414
Pulmonary Function Testing
Module 1.0
Indications For PFT

Learning Objectives





Categorize PFTs according to specific purposes
Identify at least one indication for spirometry,
lung volumes, and diffusing capacity
List one obstructive and one restrictive
pulmonary disorder
Name at least two disease in which air trapping
may occur
Relate pulmonary history to indications for
performing pulmonary function tests
Pulmonary Function Testing

Purpose for PFT
Identify and quantify pulmonary
impairments
Pulmonary Function Testing

Tests can be divided into
categories

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
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
Airway Function
Lung Volumes and Gas Distribution
Diffusing Capacity
Blood Gas and Exchange Tests
Cardiopulmonary Exercise Tests
Airway Function Tests

Spirometry
(meaning the
measuring of breath) is
the most common of
the Pulmonary Function
Tests (PFTs). It
measures lung function,
specifically the direct
measurement of the
amount (volume)
and/or speed (flow) of
air that can be inhaled
and exhaled.
Airway Function Tests

Spirometry

Vital Capacity (VC)
Airway Function Tests

Spirometry

Forced Vital Capacity (FVC)
Airway Function Tests

Spirometry

Flow – Volume Loop (FVL)

AKA; MEFV Curve
Airway Function Tests

Spirometry

Flow – Volume Loop (FVL)

AKA; MEFV Curve
Airway Function Tests

FVC and/or FVL

Pre/Post Bronchodilator

Pre/Post Bronchochallenge
Methacholine
 Histamine
 Exercise

Airway Function Tests

Spirometry

Maximum Voluntary Ventilation (MVV)
Airway Function Tests

Maximal Inspiratory (MIP)

Expiratory Pressure (MEP)

Airway Resistance (Raw)

Compliance (CL)
Indications for Spirometry

Detect the presence of lung disease
Spirometry is recommended as the
“Gold Standard” for diagnosis of
obstructive lung disease by:
National
Lung Health Education Program
National
Heart, Lung and Blood Institute
(NLHEP)
(NHLBI)
World
Health Organization (WHO)
Indications for Spirometry BOX 1-2

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Diagnose the presence or absence of lung
disease
Quantify the extent of known disease on
lung function
Measure the effects of occupational or
environmental exposure
Determine beneficial or negative effects of
therapy
Indications for Spirometry BOX 1-2

Assess risk for surgical procedures

Evaluate disability or impairment

Epidemiologic or clinical research involving
lung health or disease
Lung Volumes


Determination of lung
volume
Includes the VC
(spirometry) and its
subdivisions, along
with the FRC (indirect
spirometry) – from
these TLC and other
lung volumes can be
determined
Lung Volumes

Functional Residual Capacity (FRC)

Nitrogen Washout

Helium Dilution

Thoracic Gas Volumes
Indications for Lung Volume Tests
Box 1-3


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Diagnose or assess the severity of
restrictive lung disease
Differentiate between obstructive and
restrictive disease patterns
Assess the response to therapy
Make preoperative assessment of patients
with compromised lung function
Indications for Lung Volume Tests
Box 1-3
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Determine or evaluate disability
Assess gas trapping by comparison of
plethysmographic lung volumes with gas
dilution lung volumes
Standardize other lung functions (i.e.,
specific conductance)
Ventilation

Minute Ventilation

Alveolar Ventilation

Dead Space
Distribution of Ventilation

Multiple – Breath N2
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He Equilibration
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Single – Breath Techniques
Diffusing Capacity (DLco)
Diffusing Capacity (DLco)
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Single – Breath (Breath Hold)

Steady – State

Other Techniques
Indications for Diffusing Capacity
Box 1-4
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Evaluate or follow the progress of
parenchymal lung disease
Evaluate pulmonary involvement in
systemic disease
Evaluate obstructive lung disease
Indications for Diffusing Capacity
Box 1-4

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Evaluate cardiovascular diseases
Quantify disability associated with
interstitial lung disease
Evaluate pulmonary hemorrhage,
polycythemia, or left-to-right shunts
Blood Gases and Gas Exchange
Blood Gases and Gas Exchange

Blood Gas Analysis and Oximetry

Shunt Study
Blood Gases and Gas Exchange

Pulse Oximetry and Capnography
Indications for Blood Gas Analysis
Box 1-5
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Evaluate the adequacy of lung function
Determine the need for supplemental
oxygen
Monitor ventilatory support
Indications for Blood Gas Analysis
Box 1-5
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Document the severity or progression of
know pulmonary disease
Provide data to correct or corroborate other
pulmonary function measurement
Cardiopulmonary Exercise Test
Indications for Exercise Testing
Box 1-6


Determine the level of cardiorespiratory
fitness
Document or diagnose exercise limitations
as a result of fatigue, dyspnea, or pain,

Cardiovascular / Pulmonary Disease
Indications for Exercise Testing
Box 1-6
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Evaluate adequacy of arterial oxygenation
oxyhemoglobin saturation
Assess preoperative risk

Lung resection or reduction
Indications for Exercise Testing
Box 1-6
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Assess disability
 Occupational lung disease
Evaluate therapeutic interventions such as
heart or lung transplant
Patterns of Impaired Pulmonary Function
Sometimes, patients display
patterns during pulmonary function
testing that are consistent with a
specific diagnosis
Obstructive Airway Diseases
Simple definition:
“Airflow into and out of the lungs is
reduced”
Obstructive Airway Diseases

Chronic Obstructive Pulmonary
Disease (COPD)
Long-standing airway obstruction caused
by:

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Cystic Fibrosis
Bronchitis
Asthma
Bronchiectasis
Emphysema
“CBABE”
Obstructive Airway Diseases
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COPD
Characterized by:
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Dyspnea at rest or with exertion
Productive cough
Obstructive Airway Diseases
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Emphysema “air trapping”
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
Primarily caused by cigarette smoking!
Genetic defect; absence of
α-antitrypsin
Chronic exposure to environmental
pollutants
Obstructive Airway Diseases
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Emphysema
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Dyspnea at rest or with exertion
Productive cough
Under weight
Barrel-chested
Use of accessory muscles
Obstructive Airway Diseases
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Emphysema
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Purse-lip breathing
Breath sounds are distant or absent
Chest X-Ray
Flattened diaphragms
 Increased air spaces

Obstructive Airway Diseases
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Emphysema

Airway obstruction

Spirometry
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FEV1 is reduced
Air trapping

Lung Volumes
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Hyperinflation of FRC
Obstructive Airway Diseases
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Emphysema (cont)
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Gas exchange abnormalities
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Diffusing Capacity (DLco)

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Blood Gases
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Reduced
Hypoxemia/Hypercapnia
Possible O2 Desaturation with Exertion

Exercise Testing
Obstructive Airway Diseases
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Chronic Bronchitis
“Excessive mucus production, with
a productive cough on most days,
for at least 3 months for 2 years or
more.”
Obstructive Airway Diseases
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Chronic Bronchitis
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
Primarily caused by
cigarette smoking!
Chronic exposure to
environmental pollutants
Obstructive Airway Diseases
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Chronic Bronchitis
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Chronic cough – “smoker’s cough”
Dyspnea, particularly with exertion
Chest X-Ray
Congested airways
 Enlarged heart w/prominent pulmonary
vessels
 Diaphragms normal or flattened
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
Edema of lower extremities
Obstructive Airway Diseases
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Chronic Bronchitis (cont)
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Airway obstruction

Spirometry

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FEV1 is reduced
Dlco
Usually reduced
 May have a preserved (normal) Dlco,
which is helpful to distinguish it from
emphysema
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Obstructive Airway Diseases
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Chronic Bronchitis (cont)
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Gas exchange abnormalities
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Blood Gases
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Hypoxemia, Hypercapnia in advanced cases
 Polycythemia
 Cyanosis
Obstructive Airway Diseases
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Bronchiectasis
Pathologic dilatation of the bronchi,
resulting from destruction of the
bronchial wall by severe, repeated
infections.
Obstructive Airway Diseases
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Bronchiectasis
Common in Cystic Fibrosis (CF), as
well as following bronchial
obstruction by a tumor or foreign
body. When entire bronchial tree is
involved, it is assumed that the
disease is inherited.
Obstructive Airway Diseases
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Bronchiectasis
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Dyspnea
Very productive cough
Purulent, foul smelling sputum
Hemoptysis is common
Obstructive Airway Diseases
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Bronchiectasis
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Frequent pulmonary infections
Right-sided heart failure when
advanced
Appear chronically ill - under weight
Chest X-Ray / CT Scan

Airway Dilation
Obstructive Airway Diseases
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Bronchiectasis (cont)
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Airway obstruction
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Spirometry
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Lung Volumes
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FEV1 is reduced
Hyperinflation
Gas exchange abnormalities

Blood Gases
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Hypoxemia, Hypercapnia in advanced cases
Obstructive Airway Diseases
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Asthma (Hypereactive Airway Disease)
Reversible airway obstruction.
Obstruction is characterized by
inflammation of the mucosal lining of
the airways, bronchospasm, and
increased airway secretions.
Obstructive Airway Diseases

Asthma (Hypereactive Airway Disease)

Triggers; agents or events that cause an
asthmatic episode
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Allergic agents
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
Nonallergic agents

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Pollens, animal dander, house dust mites,
molds
Viral infections, exercise, cold air, air
pollutants, drugs, food additives, emotional
upset
Occupational exposure

Toluene 2,4-diisocyanate (TDI), cotton or wood
dusts, grain, metal salts, insecticides
Obstructive Airway Diseases
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Asthma (cont)
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Airway obstruction
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During Attacks
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Peak Flow (PEF) is reduced, also used to track
response to bronchodilators
Blood Gases
 Hypoxemia
During Diagnosis
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Airway Resistance (Raw)
Spirometry, Pre/Post Bronchodilator
Bronchial Provocation if airways appear normal
Obstructive Airway Diseases
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Cystic Fibrosis
An inherited disease that primarily
affects the mucus-producing
apparatus of the lungs and
pancreas.
Obstructive Airway Diseases

Cystic Fibrosis

Airway obstruction

Spirometry


FEV1 used to monitor the progression of the
disease
Pulmonary function studies are routinely
used to assess lung function following
transplantation
Obstructive Airway Diseases
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Upper or Large Airway Obstruction
(Upper: nose, mouth, pharynx)
(Large: Trachea, mainstem bronchi)

Increased work of breathing

Spirometry

Flow-Volume Loop
Restrictive Lung Disease
Characterized by:

Reduction in
lung volumes

(Vital Capacity
(VC) and Total
Lung Capacity
(TLC) are both
reduced below
the lower limits
of normal.
Restrictive Lung Disease
Any process that interferes with
the bellows action of the lungs
or chest wall can cause
restriction.
Restrictive Lung Disease

Idiopathic Pulmonary Fibrosis
Characterized by alveolar wall
inflammation resulting in fibrosis.
Vascular changes are usually
associated with pulmonary
hypertension.
Restrictive Lung Disease
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Idiopathic Pulmonary Fibrosis

IPF often follows
Treatment with bleomycin,
cyclophosphamide, methotrexate or
amiodarone
 Autoimmune diseases


Rheumatoid arthritis, systemic lupus
erythematousus (SLE), scleroderma
Restrictive Lung Disease
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Idiopathic Pulmonary Fibrosis
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Increasing exertional dyspnea
Pulmonary hypertension
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
Vascular changes
Chest X-Ray
Infiltrates are visible
 Honeycombing pattern when advanced

Restrictive Lung Disease

Idiopathic Pulmonary Fibrosis

Spirometry
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
Reduced VC
Lung Volumes
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Reduced TLC
Restrictive Lung Disease
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Idiopathic Pulmonary Fibrosis
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Gas exchange abnormalities
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Reduced DLco
Blood Gases
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Hypoxemia; worsens with exertion
Lung compliance

Reduced
Restrictive Lung Disease
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Pneumoconiosis
Lung impairment caused by
inhalation of dusts.
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Silicosis – Silica dust
Asbestosis – Asbestos fibers
Coal Worker’s Pneumoconiosis – Coal
dust
Restrictive Lung Disease

Pneumoconiosis (cont)

Spirometry
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
Lung Volumes
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
Reduced VC
Reduced TLC
Gas exchange abnormalities
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
Decreased Diffusing Capacity (DLco)
Blood Gases

Hypoxemia
Restrictive Lung Disease

Sarcoidosis
Granulomatous disease that affects
multiple organ systems. The
granuloma found in sarcoidosis is
composed of macrophages,
epithelioid cells, and other
inflammatory cells.
Restrictive Lung Disease

Sarcoidosis

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
Fatigue
Muscle weakness
Fever
Weight loss
Dyspnea and cough
Chest X-Ray
Enlargement of hilar and mediastinal
lymph nodes
 Interstitial infiltrates

Restrictive Lung Disease

Sarcoidosis

Spirometry



Lung Volumes


Reduced VC
Normal Flow Rates
Reduced TLC
Gas exchange abnormalities


Decreased Diffusing Capacity (DLco) when
advanced
Blood Gases

Normal or hypoxemia
Diseases of Chest Wall and Pleura
Disorders involving the chest wall or
pleura of the lungs result in
restrictive patterns on pulmonary
function testing.
Diseases of Chest Wall and Pleura

Kyphoscoliosis
Abnormal curvature of the spine
both anteriorly (kyphosis) and
lateraly (scoliosis).
Diseases of Chest Wall and Pleura

Kyphoscoliosis

Spirometry


Lung Volumes


Reduced VC
Reduced TLC
Gas exchange abnormalities


Decreased Diffusing Capacity (DLco)
Blood Gases (Hypoxemia / Hypercapnia)
Diseases of Chest Wall and Pleura

Obesity
Increased mass of the thorax and
abdomen interferes with the bellows
action of the chest wall, as well as
excursion of the diaphragm.
Diseases of Chest Wall and Pleura
 Obesity

Spirometry
Reduced VC
 Normal Flow Rates


Lung Volumes

Reduced TLC
Diseases of Chest Wall and Pleura

Obesity

Gas exchange abnormalities
Decreased Diffusing Capacity (DLco)
 Blood Gases


Hypoxemia / Hypercapnia
 Polycythemia
 Pulmonary Hypertension
 Cor pulmonale
Diseases of Chest Wall and Pleura

Pleurisy and Pleural Effusion
Pleurisy is characterized by
deposition of a fibrous exudate on
the pleural surface – often
associated with pneumonia or
cancer. May precede the
development of pleural effusion.
Diseases of Chest Wall and Pleura

Pleurisy and Pleural Effusion
Plural effusion is an abnormal
accumulation of fluid in the pleural
space.
Diseases of Chest Wall and Pleura

Pleurisy and Pleural Effusion

Spirometry
Reduced VC because of volume loss
 Difficulty performing because of pain


Lung Volumes

Reduced TLC because of volume loss
Diseases of Chest Wall and Pleura

Pleurisy and Pleural Effusion

Gas exchange abnormalities
DLco – Difficulty performing due to pain
 Blood Gases


Large effusions may cause changes
Neuromuscular Disorders
Disease that affect the spinal cord,
peripheral nerves, neuromuscular
junctions, and the respiratory
muscles can all cause a restrictive
pattern of pulmonary function.
Neuromuscular Disorders

Diaphragmatic paralysis

Amyotrophic Lateral Sclerosis
(ALS, Lou Gehrig’s disease)

Guillain – Barre’ syndrome

Myasthenia gravis
Neuromuscular Disorders

Spirometry


Reduced VC
Lung Volumes

Reduced TLC
Neuromuscular Disorders

Gas exchange abnormalities

Blood Gases



Hypoxemia if involvement is severe
Respiratory alkalosis from hyperventilation
Inspiratory Pressures

MIP - Reduced
Congestive Heart Failure
Often caused by left ventricular
failure, but may also be associated
with cardiomyopathy, congenital
heart defects, or left-to-right
shunts. In each case, fluid backs
up in the lungs.
Congestive Heart Failure

Spirometry


Reduced VC
Lung Volumes

Reduced TLC
Congestive Heart Failure

Gas exchange abnormalities
DLco is reduced
 Blood Gases



Hypoxemia
Lung Compliance

Reduced
Lung Transplantation
Lung transplantation has been used
for patients with CF, primary
pulmonary hypertension, and COPD.
Lung Transplantation
Pulmonary function testing is used
to both assess potential transplant
candidates and follow them
postoperatively.
Preliminaries to Patient Testing

Patient Preparation

Withholding Medications


Smoking Cessation


Bronchodilator held 4-6 hours prior to test
Should be ceased 24 hours prior to test
Eating should be limited
Preliminaries to Patient Testing

Physical Measurements
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
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Age
Height (arm span if unable to stand)
Weight
Gender
Race or Ethnic Origin
Preliminaries to Patient Testing

Physical Assessment

Breathing Patterns

Breath Sounds

Respiratory Symptoms
Preliminaries to Patient Testing

Pulmonary History



Age, gender, height, weight, race
Current Dx. or reason for test
Family History (immediate family: mother,
father, brother, or sister)







Tuberculosis
Emphysema
Chronic Bronchitis
Asthma
Hay fever or allergies
Cancer
Other lung disorders
Preliminaries to Patient Testing

Pulmonary History

Personal History









Tuberculosis
Emphysema
Chronic Bronchitis
Asthma
Recurrent lung infection
Pneumonia or pleurisy
Allergies or hay fever
Chest injury
Chest surgery
Preliminaries to Patient Testing

Occupation



What was your occupation?
How long did you work there?
Have you ever worked in …
Mine, quarry, foundry?
 Near gases or fumes?
 Dusty environment?

Preliminaries to Patient Testing

Smoking Habits

Have you ever smoked the
following:
Cigarettes (how many per day?)
 Cigars (how many per day?)
 Pipe (how many bowls per day?)
 How many years?
 Do you still smoke?
 Do you live with a smoker?

Preliminaries to Patient Testing

Cough

Do you ever cough?
In the morning?
 At night?
 Blood?
 Phlegm? (when, color, volume)

Preliminaries to Patient Testing

Dyspnea

Do you get short of breath at the
following times:
At rest?
 On exertion?
 At night?

Preliminaries to Patient Testing

Patient Disposition






Dyspneic
Wheezing
Coughing
Cyanotic
Apprehensive
Cooperative
Preliminaries to Patient Testing

Current Medications

Heart, lung, or blood pressure?

Last taken?
Test Performance

Patient Instruction



Many tests are effort dependent
Instruction & coaching very
important
Demonstration a must
Test Performance

Patient Instruction



Encouragement during test
Suboptimal effort results in poor
reproducibility
Documentation of effort important
Practice / Review
Which of the following are indications
for performing spirometry?
I. Assess the risk of lung resection
II. Determine the response to
bronchodilator therapy
III. Assess the severity of restrictive lung
disease
IV. Quantify the extent of COPD
a. I and IV
b. II and III
c. I, II, and IV
d. II, III, and IV
Practice / Review
Which of the following symptoms is an
indication for performing spirometry?
A. Headache
B. Shortness of breath
C. Chest pain
D. Daytime sleepiness
Practice / Review
Which of the following tests would be
indicated to assess the severity of a
restrictive lung disease?
A. Blood gas analysis
B. Simple spirometry
C. Lung volume determination
D. Cardiopulmonary exercise test
Practice / Review
Which of the following tests would
be indicated in the evaluation of a
patient exposed to dust including
asbestos?
A. Shunt study
B. DLco
C. Methacholine challenge
D. Airway Resistance
Practice / Review
A 17-year old female complains of
chest tightness and cough after
soccer practice. These symptoms are
most consistent with which of the
following?
A. Emphysema
B. Congestive heart failure
C. Asthma
D. Cystic fibrosis
Practice / Review
Which of the following diseases
often results in an obstructive
pattern when simple spirometry is
performed?
A. Sarcoidosis
B. Idiopathic pulmonary fibrosis
C. Pleurisy
D. Chronic bronchitis
Practice / Review

Lung volumes measured by closed –
circuit He dilution may be expected
to show a reduced FRC in which of
the following?
A. Emphysema
B. Asthma
C. Pulmonary fibrosis
D. Upper airway obstruction
Practice / Review
Which of the following should a pulmonary
function technologist do before performing
spirometry?
a.
b.
c.
d.
Limit feedback to the patient to limit placebo
effect
Explain the physiologic basis of the test
Demonstrate how to correctly perform the test
maneuver
Explain the exact number of efforts that will be
required for the test
Practice / Review
Pulmonary function testing is
usually contraindicated in which of
the following conditions?
A. Untreated pneumothorax
B. Congestive heart failure
C. Cyanosis
D. Tuberculosis
Practice / Review

In which of the following diseases is
air-trapping likely to occur?
A. Acute exacerbation of asthma
B. Sarcoidosis
C. Asbestosis
D. Emphysema
E. B & C
F. A & D
Practice / Review
Which of the following correctly describes
appropriate physical measurements before
pulmonary function testing?
I. Actual body weight should be used to calculate
predicted values
II. Standing height should be measured when the
patient is barefoot
III. Arm span should be used instead of height for
a patient with kyphosis
IV. Age should be recorded to the nearest decade
(10 years)
a. I only
b. II and III
c. I, II, and IV
d. I, II, III, and IV