Asthma II Part 2: Diagnosis, Pulm Func Tests

Question 1

Asthma Diagnosis (GINA)
general - read

Answer 1

no single diagnostic test

• based on a history of characteristic symptom patterns and evidence of variable airflow limitation (from bronchodilator reversibility testing)
• Usually characterized by airway inflammation and hyperresponsiveness, but not necessary

Question 2

Asthma Diagnosis (GINA)

2 key defining features

Answer 2

1. History of respiratory symptoms such as wheeze, SOB, chest tightness and cough that varies over time and intensity, AND
2. Variable expiratory airflow limitation

Question 3

Asthma Diagnosis (GINA)

what features increase prob of asthma?

Answer 3

• more than one symptom (wheeze, SOB, cough, tightness) esp in adults
• worse at night/early morning
• vary over time and intensity
• symptoms triggered by viral infections, exercise, allergen exposure, weather, laughter, irritants

Question 4

Asthma Diagnosis (GINA)

what features decrase prob of asthma?
read

Answer 4

• isolated cought w/o resp symptoms
• chronic pdtn of sputum
• SOB w/ dizziness, light-headedness, periph tingling
• chest pain
• exercise induced dyspnea w/ noisy inspiration

Question 5

Asthma “Diagnosis” in the Pharmacy

initial screening qs
In the past 4 wks have you had any asthma symptoms ______ (3)

Answer 5

 upon awakening?
 at night that have awakened you?
 after moderate exercise or physical activity?

Question 6

Asthma “Diagnosis” in the Pharmacy

initial screening qs
In the past 12 months have you had any of the following ______ (5)

Answer 6

 Sudden, severe episodes of asthma symptoms?
 Colds that “end up in your chest” or last >10 days?
 Asthma symptoms at a particular time of year?
 Asthma symptoms after certain exposures?
 If you have inhalers, are symptoms relieved when they’re used?

Question 7

Asthma Diagnosis & Evaluation

3 considerations
start w/ open ended qs and proceed w/ more targeted q’s

Answer 7

1. Patient history
   • Determines a patient’s level of asthma control and identifies where patient education might be required
2. Physical examination
   • Relevant when a patient is symptomatic; not necessarily used for diagnosis
3. Pulmonary function
   • Pulmonary function tests assess lung function and may be used for diagnosis

Question 8

1. Pt history

see tables for SCHOLAR-E qs to ask

Answer 8

ok

Question 9

2. Physical Examination
   - may be normal but what should you consider? (4)
   Focus is on upper respiratory tract, chest, and skin
   doctor for complete phys exam

Answer 9

• Most common abnormal physical finding is expiratory wheezing on auscultation (listening through a stethoscope)
• Hyperexpansion of the thorax - especially in children; use of accessory muscles; appearance of hunched shoulders and chest deformity
• Increased nasal secretion, mucosal swelling, and/or nasal polyps

triad
• Signs and symptoms of allergic rhinitis
• Atopic dermatitis/eczema or other manifestations of an allergic skin condition

Question 10

3. Pulmonary Function

define pulm func tests
what 3 main tests are used?

*some tests may be normal! Need a
multifaceted assessment

Answer 10

objective measure of how well the lungs are working (functioning):
• Test to diagnose asthma and differentiate other conditions
• Monitor therapeutic intervention

main tests
1. Spirometry
 Very common
2. Peak Expiratory Flow (PEF)
 An alternative but mostly used for monitoring
3. Bronchoprovocation Challenge Tests
 More specialized tests

Question 11

3. Pulmonary Function

spirometry

what ages can use it?
why does both the CTS and GINA guidelines
recommend spirometry as the measure of
airflow limitation and reversibility to
establish a diagnosis of asthma

Answer 11

In most cases, this test can be properly administered to individuals >6 years of age.

• Spirometry is the most reproducible and
objective measurement of airflow limitation available

Question 12

3. Pulmonary Function

spirometry

how does it work?
limitations?

Answer 12

A spirometer measures:
• How much air can be blown out of the lungs (volume) after a maximal inspiration
• The results are reported as FEV1 and FVC (forced vital capacity)

• How quickly air can be blown out (flow)

Limitations:
• The test must be administered properly, and the individual taking the test must be able to perform it

Question 13

3. Pulmonary Function

spirometry

define FEV1, FVC, FEV1/FVC

Answer 13

• FEV1 = forced expiratory volume in the 1st second
• FVC = forced vital capacity (max volume exhaled)
• FEV1/FVC = proportion or percentage of total air volume exhaled in 1st second
• The ratio of FEV1/FVC is a measure of airflow obstruction
• Both FEV1 and FVC are based on the patient’s size, age, sex, and race

Question 14

3. Pulmonary Function

spirometry

when can a diagnosis be made? (2)

Answer 14

• There is a reduced FEV1/FVC ratio

* If there is a significant change in FEV1

Question 15

3. Pulmonary Function

spirometry

what is bronchodilator reversibility?
what should you remember for post-bronchodilator testing? (read)

Answer 15

• FEV1 improvement of at least 12% and 200 mL after administration of a bronchodilator
• Short-acting bronchodilators need to be withheld for at least 6-8 hours prior to testing.
• Long-acting bronchodilators should be withheld for 12 to 24 hours prior to testing.
• Notation should be made on the test results regarding the last dose of any long- or short-acting bronchodilator.
• Beta blockers will blunt the effect of the beta agonists, and the patient should be assessed for the need for holding these medications for spirometry.

Question 16

3. Pulmonary Function

spirometry
Adolescents and Adults

criteria that shows reversible airway obs
Reduced FEV1 / FVC of ________

Increase in FEV1 after bronchodilator or course of controller therapy of ________

Answer 16

Reduced FEV1 / FVC
Less than lower limit of normal (<0.75 – 0.8)

AND

Increase in FEV1 after bronchodilator or course
of controller therapy >12%* (and a minimum
of >200mL)

Question 17

3. Pulmonary Function

spirometry
Children >6

criteria that shows reversible airway obs
Reduced FEV1 / FVC of ________

Increase in FEV1 after bronchodilator or course of controller therapy of ________

Answer 17

Reduced FEV1 / FVC
Less than lower limit of normal (<0.8 – 0.9)

AND

Increase in FEV1 after bronchodilator or course
of controller therapy >12%

Question 18

look at obstructive vs restrictive curve

Answer 18

ok

Question 19

3. Pulmonary Function

Peak Expiratory Flow

device?
what does it measure?
use?

Answer 19

peak flow meter
• Peak expiratory flow (PEF) is the measurement of the
maximum exhaled flow rate and provides information
about the caliber (diameter) of the airways (wider
airways are capable of achieving higher PEF rate).
• Used more for monitoring rather than for diagnosing

Question 20

3. Pulmonary Function

Peak Expiratory Flow

steps to do it

Answer 20

Requires patient involvement and training.
• The patient takes a deep breath in as possible and blows it out as hard and fast as possible (consistent effort needed).
• It is an individual’s personal best PEF that should be used as a reference value for monitoring the effects of changes in treatment and evaluating asthma control.
• The optimal time to determine personal best peak flow rate is when the patient is asymptomatic
• Use same device for repeated measurements

Question 21

3. Pulmonary Function

Peak Expiratory Flow

how often should you do it?

Answer 21

• GINA guidelines recommend diurnal measurement of peak flow readings for two weeks.
• Measurements are taken in the morning, when peak flow readings are usually at their lowest, and in the period of late afternoon to bedtime, when they are usually at their highest

Question 22

3. Pulmonary Function

Peak Expiratory Flow

Adolescents and Adults

Increase in PEV after bronchodilator or course of controller therapy of ________

OR

Diurnal Variation of ________

Answer 22

60L/min (minimum >20%)

OR

> 10% based on twice daily readings
20% based on multiple daily readings (done to identify potential triggers e.g. irritants)

Question 23

3. Pulmonary Function

Peak Expiratory Flow

Children >6

Increase in PEV after bronchodilator or course of controller therapy of ________

Diurnal Variation of ________

Answer 23

> 20%

diurnal variation testing not recommended

Question 24

3. Pulmonary Function

Peak Expiratory Flow
asthma action plan
what are the % of personal best in green, yellow, red zone

Answer 24

green: 80-100%
yellow: 50-80%
red: under 50%

Question 25

3. Pulmonary Function Bronchoprovocation Challenge Tests Methacholine Challenge Test

Answer 25

 After a baseline FEV1 is taken, this substance is administered by inhalation in 0.25 mg increments (to a maximum of 16mg) and an FEV1 is taken after each dose. The intention is to induced bronchoconstriction.  An FEV1 decrease of 20% indicates airway hyperresponsiveness  Not performed in pregnancy due to lack of data on safety

Question 26

3. Pulmonary Function Bronchoprovocation Challenge Tests Exercise Challenge Test

Answer 26

 Appropriate for those with exercise-induced symptoms |  FEV1 is measured before and after exercise on a bike or treadmill

Question 27

3. Pulmonary Function other tests - read more on slides

Answer 27

* Chest radiograph * Allergy testing * Exhaled nitric oxide * Sputum Cell Counts