Download Easy Spirometry Interpretation Guide

Easy Spirometry Interpretation Guide
5. A normal volume-time curve
The most important tools
for diagnosing COPD
and asthma are medical
history, physical examination, and spirometry.
Interpreting your spirometry results correctly will
help assure an accurate
diagnosis and disease
classification (severity).
rises sharply from the baseline
and reaches a flat plateau. A
gradual curve that never plateaus
suggests airway obstruction.
Sample V/T curves
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2. Look at the curve patterns
and
numbers
to8 help guide your
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olume (L) interpretation.
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FEV1=4.0 L
FEV1=1.8 L
2
Time (sec)
that the quality of the spirometry
test is good. Poor quality tests
can cause diagnostic misclassifications. For more information,
see 10 Steps to Good Results on
our website.
3. A normal flow-volume curve
looks like a sail, rising rapidly to a
peak then descending at about a
45-degree angle.
4. A concave flow-volume curve
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FVC=4.2 L
FVC=5.0 L
6
Volume (L)
suggests mild to moderate airways obstruction, while a prolonged finish “rat’s tail shape”
suggests severe obstruction.
Note: If the effort stops before 6
seconds in adults (3 seconds in
children) the FVC may be underestimated.
Normal
Moderate Obstruction
Severe Obstruction
Sample F/V curves
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respiratory symptoms and normal
spirometry, consider performing a
post-BD test to identify intermittent or mild asthma which is confirmed by a >12% improvement
in FEV1, despite normal pre-BD
spirometry results.
9. Adult onset airway obstruction
in the long-term smoker (>10 to
20 pack year history) is usually
due to COPD.
10. Once a diagnosis of asthma
or COPD has been determined,
disease classification and approTo view additional curve samples,
priate
treatment can be easily
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00
see Sample Spirometry
Tracings
established by utilizing the
Normal
on our website.
Severe Obstruction
corresponding tables on the
1
6. A low (< 70%
pred) FEV1%
following page.
FEV1=4.0 L
(FEV1/FVC) indicates
FEV1=1.8 L airway
If a diagnosis is still uncertain,
obstruction. A low
(< 80% pred)
2
consider referral to a specialist
FVC and FEV1 with a normal
for consultation or co-manageFEV1% suggests restriction with3
ment.
out obstruction. However, to
make a definitive diagnosis of
restrictive lung 4disease, the
patient should be referred to a
pulmonary lab for
additional lung
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Jones Medical Instrument Company
volume testing.
FVC=5.0 L
200 Windsor Drive, Oak Brook, IL 60523
FVC=4.2 L
Time (sec)
5
airway obstruction should receive
a post-BD (bronchodilator)
spirometry test. After administration of a bronchodilator (i.e.,
albuterol, 2-4 puffs of 90
mcg/puff), allow 10-15 minutes
prior to performing the post BD
spirometry test. An increase of
12% (and more than 0.2 liters) in
the measured FEV1 suggests
reversible airways disease, such
as asthma. COPD can be as
much as 5-6% reversible, but not
much more. For more information, see Differential Diagnosis on
our website.
8. In patients with intermittent
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Flow (L/sec)
2
Normal
Severe Obstruction
1. The first step is to make sure
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1
0
1
7. Patients with symptoms and
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Volume (L)
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(800) 323-7336 • www.jonesmedical.com
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©2008 Jones Medical Instrument Company. All Rights Reserved.
Volume (L)
Classification: First, identify the appropriate classification chart below. Then simply reference the
patients’ post-BD spirometry results to determine an accurate classification and treatment regimen.
CLASSIFYING ASTHMA SEVERITY IN CHILDREN 5 - 11
YEARS OF AGE
STEPWISE APPROACH FOR MANAGING ASTHMA IN
CHILDREN 5 - 11 YEARS OF AGE
Assessing severity and initiating therapy in children who are not currently taking long-term control medication
Classification of Asthma Severity
(5 - 11 years of age)
Components of
Severity
Symptoms
Nighttime
awakenings
Short acting
beta2-agonist use for
symptom control (not
prevention of EIB)
Interference with
normal activity
Moderate
Severe
≤2 days/week
>2 days/week but
not daily
Daily
Throughout
the day
≤2x/month
3 - 4x/month
>1x/week but
not nightly
Often 7x/week
Daily
Several times
per day
>2 days/week
but not daily
≤2 days/week
None
Minor limitation
• FEV1 >80%
predicted
• FEV1/FVC >85%
• FEV1 = >80%
predicted
• FEV1/FVC >80%
0 - 1/year
Exacerbations
requiring oral
systemic
corticosteroids
Some limitation
• FEV1 = 60-80%
predicted
• FEV1/FVC = 75-80%
• FEV1 <60%
predicted
• FEV1/FVC < 75%
Step 3, medium- Step 3, medium-dose
dose ICS option
ICS option or Step 4
and consider short course of
oral systemic corticosteroids
Step 2
In 2 - 6 weeks, evaluate level of asthma control that is achieved,
and adjust therapy accordingly
CLASSIFYING ASTHMA SEVERITY IN YOUTHS ≥12 YEARS OF AGE
AND ADULTS
Preferred:
Step 3
Preferred:
High-dose ICS +
LABA
Step 2
Preferred:
Medium-dose
ICS + LABA
Alternative:
Preferred:
EITHER:
Alternative:
High-dose ICS +
either LTRA
or Theophylline
Step 1
Low-dose ICS
Preferred:
Alternative:
SABA PRN
Cromolyn, LTRA,
Nedocromil, or
Theophylline
Low-dose ICS +
either LABA,
LTRA, or
Theophylline
OR
Medium-dose
ICS
Medium-dose
ICS + either
LTRA or
Theophylline
Preferred:
High-dose ICS +
LABA + oral
systemic
corticosteroid
Alternative:
High-dose ICS +
either LTRA
or
Theophylline +
oral systemic
corticosteroid
Each Step: Patient education, environmental control, and management of comorbidities.
Steps 2 - 4: Consider subcutaneous allergen immunotherapy for patients who have allergic asthma.
Step up if
needed
(first, check
adherence,
inhaler
technique,
environmental
control, and
comorbid
conditions)
Assess
control
Step down if
possible
(and asthma is
well controlled
at least
3 months)
Quick-Relief Medication for All Patients
• SABA as needed for symptoms. Intensity of treatment depends on severity of symptoms: up to 3 treatments
at 20-minute intervals as needed. Short course of oral systemic corticosteroids may be needed.
• Caution: Increasing use of SABA or use >2 days a week for symptom relief (not prevention of EIB) generally
indicates inadequate control and the need to step up treatment.
STEPWISE APPROACH FOR MANAGING ASTHMA IN
YOUTHS ≥12 YEARS OF AGE AND ADULTS
Assessing severity and initiating treatment for patients who are not currently taking long-term control medications
Classification of Asthma Severity
≥12 years of age
Mild
Moderate
Severe
≤2 days/week
>2 days/week but
not daily
Daily
Throughout
the day
Nighttime
awakenings
≤2x/month
3 - 4x/month
>1x/week but
not nightly
Often 7x/week
Short acting
beta2-agonist use for
symptom control (not
prevention of EIB)
≤2 days/week
Daily
Several times
per day
Symptoms
Impairment
Normal FEV1/FVC:
8 - 19 yr 85%
20 - 39 yr 80%
40 - 59 yr 75%
60 - 80 yr 70%
Interference with
normal activity
None
Lung function
• Normal FEV1
between
exacerbations
• FEV1 >80%
predicted
• FEV1/FVC normal
Risk
Minor limitation
• FEV1 >80%
predicted
• FEV1/FVC normal
Some limitation
• FEV1 >60%, but
<80% predicted
• FEV1/FVC
reduced 5%
Extremely limited
• FEV1 <60%
predicted
• FEV1/FVC
reduced >5%
Step 3
Step 1
Step 2
II: Moderate
FEV1 ≥ 80% predicted
•
•
FEV1/FVC < 0.70
50% ≤ FEV1 < 80%
predicted
Step 2
Step 1
Step 4 or 5
and consider short course of
oral systemic corticosteroids
III: Severe
•
•
FEV1/FVC < 0.70
30% ≤ FEV1 < 50%
predicted
IV: Very Severe
•
•
FEV1/FVC < 0.70
FEV1 < 30% predicted
or FEV1 < 50%
predicted plus chronic
respiratory failure
Alternative:
SABA PRN
Cromolyn, LTRA,
Nedocromil, or
Theophylline
Low-dose
ICS + LABA
OR
Medium-dose
ICS
Alternative:
Preferred:
Step 4
Preferred:
Preferred:
High-dose ICS +
LABA
Medium-dose
ICS + LABA
AND
AND
Consider
Omalizumab for
patients who
have allergies
Consider
Omalizumab for
patients who
have allergies
Alternative:
Medium-dose
ICS + either
LTRA,
Theophylline,
or Zileuton
High-dose ICS +
LABA + oral
corticosteroid
Low-dose ICS +
either LTRA,
Theophyline, or
Zileuton
Steps 2 - 4: Consider subcutaneous allergen immunotherapy for patients who have allergic asthma.
(first, check
adherence,
environmental
control, and
comorbid
conditions)
Assess
control
Step down if
possible
(and asthma is
well controlled
at least
3 months)
• SABA as needed for symptoms. Intensity of treatment depends on severity of symptoms: up to 3 treatments
at 20-minute intervals as needed. Short course of oral systemic corticosteroids may be needed.
• Use of SABA >2 days a week for symptom relief (not prevention of EIB) generally indicates inadequate control and
the need to step up treatment.
Visit the Links page on our website for complete
versions of the asthma and COPD guidelines.
Note: This information is intended to augment,
not replace, a physician’s independent
professional judgment.
NHLBI/WHO. GOLD COPD Guidelines; 2006 Revised
NHLBI. Guidelines for the Diagnosis and Management of Asthma:
Expert Panel Report 3: 2007
Add inhaled glucocorticosteroids if
repeated exacerbations
Add long-term oxygen if
chronic respiratory
failure.
Consider surgical
treatments
Step up if
needed
Quick-Relief Medication for All Patients
2
Add regular treatment with one or more long-acting bronchodilators
(when needed); Add rehabilitation
Preferred:
Step 6
Each Step: Patient education, environmental control, and management of comorbidities.
1
Active reduction of risk factor(s); influenza vaccination
Add short-acting bronchodilator (when needed)
Low-dose ICS
Preferred:
≥2/year
Consider severity and interval since last exacerbation.
Frequency and severity may fluctuate over time for patients in any severity category.
Relative annual risk of exacerbations may be related to FEV1.
COPD CLASSIFICATION AND TREATMENT
I: Mild
Step 5
Preferred:
In 2 - 6 weeks, evaluate level of asthma control that is achieved,
and adjust therapy accordingly
FEV1/FVC < 0.70
Consult with asthma specialist if Step 4 care or higher is required.
Consider consultation at Step 3.
Step 3
>2 days/week
but not daily, and
not more than
1x on any day
0 - 1/year
Exacerbations
requiring oral
systemic
corticosteroids
Recommended Step for
Initiating Therapy
•
•
Persistent Asthma: Daily Medication
Intermittent
Asthma
Persistent
Intermittent
1
Step 4
Step 6
≥2/year
Step 1
Components of
Severity
COPD
Step 5
Extremely limited
Consider severity and interval since last exacerbation.
Frequency and severity may fluctuate over time for patients in any severity category.
Relative annual risk of exacerbations may be related to FEV1.
Recommended Step for
Initiating Therapy
ASTHMA2
Mild
• Normal FEV1
between
exacerbations
Lung function
Risk
Consult with asthma specialist if Step 4 care or higher is required.
Consider consultation at Step 3.
Persistent
Intermittent
Impairment
Persistent Asthma: Daily Medication
Intermittent
Asthma
Jones Medical Instrument Company
200 Windsor Drive, Oak Brook, IL 60523
(800) 323-7336 • www.jonesmedical.com
©2008 Jones Medical Instrument Company. All Rights Reserved.