Spirometry: a practical approach and some fun cases · 2018-11-26 · Spirometry: a practical...

Spirometry: a practical approach and some fun cases

Ron Olivenstein, MD

Montreal Chest Institute

Montreal, Quebec

November 26, 2018.

Potential for Conflict of Interest

Advisory Boards: AstraZeneca, GlaxoSmithKline,

Merck, Novartis, Sanofi.

Speakers Fees: AstraZeneca, GlaxoSmithKline,

Merck, Novartis.

Research grants:, AstraZeneca, Boehringer

Ingelheim, Boston Scientific, Genentech,

GlaxoSmithKline, Medimmune, Merck, Novartis,

Sanofi.

Objectives

• Describe the benefits of spirometry in the diagnosis of obstructive lung diseases

• Learn to interpret spirometry results

3

Why spirometry ?

30% of doctor diagnosed

asthma is found to be mistaken

when not confirmed by

spirometry

AARC Clinical Practice Guideline. Respir Care 1996;41(7):629-36.

Indications for Spirometry

• Detect the presence or absence of lung disease

• Quantify the severity of lung disease

• Assess the change in lung function over time or following administration of therapy

• Assess the potential effects of environmental or occupational exposure

• Assess impairment and/or disability

• Assess risk for surgical procedure

5

Who should be tested?

• All patients with suspected Asthma or COPD

• Smokers of > 20 pack years

– Screening vs. case finding

• Patients with significant occupational exposure to respiratory irritants

• Patients with family history of respiratory diseases

• Patients undergoing lung surgery

6

Spirometry Contraindications

• Contraindications (safety or reliability issues)

– Hemoptysis of unknown origin

– Pneumothorax

– Unstable cardiovascular status (eg. recent myocardial infarction or pulmonary embolus)

– Thoracic, abdominal, or cerebral aneurysms

– Recent eye, thorax or abdomen surgery

– Suspected TB or other contagious respiratory infection

AARC Clinical Practice Guideline. Respir Care 1996;41(7):629-36. 7

Terms and Abbreviations

• FVC – is the volume of air that can be forcibly expelled from the lung from maximum inspiration to maximum expiration

• FEV1 – the volume of air that can be forcibly expelled from maximum inspiration in the first second

• FEV1 /FVC – Ratio

• PEFR – the maximum flow rate attained during an FVC maneuver

8

Lung Function Testing: Normal Effort

9

Spirometry Criteria:

• Minimum of 3 acceptable FVC maneuvers should be performed

– Discontinue testing after 8 attempts

– No cough, especially during the first second

• Good ‘start-of-test’ includes:

– No hesitation or false start

– Rapid start to rise time

• Minimum exhalation time of 6 seconds

AARC Clinical Practice Guideline. Respir Care 1996;41(7):629-36. 10

Examples of Anomalous Spirometric Measurements

Adapted from: GOLD. Spirometry for healthcare providers; Available at: http://www.goldcopd.com/OtherResourcesItem.asp?l1=2&l2=2&intId=1836

Used with permission from the Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease, Global Initiative for Chronic Obstructive Lung

Disease (GOLD) 2008. Available from: http://www.goldcopd.org

11

Predicted Normal Values

Reference value only, not absolute right or wrong!

12

3 steps to diagnose respiratory

disorders using spirometry

1. FEV1/FVC

If less than 70% implies OBSTRUCTION

If greater than 70%: normal or restriction

2. FEV1: degree of obstruction

3. FVC:

If less than 80% implies restriction

If greater than 80% implies normal.

Criteria to determine significant

reversibility after bronchodilators

Description VEMS

% reversibilité 12% et changement absolu du 200 mL

Q1

Relationship between significant reversibility after

bronchodilator administration and asthma

• Confirms asthma in the appropriate clinical setting especially if the

FEV1/FVC ratio is normalized post bronchodilator.

• < 70% pre b-d

•> 70% pre b-d

•But is also present in many patients with COPD. However in COPD by

definition the post b-d FEV1/FVC is always < 70%

•The greater the post b-d improvement, the more likely an asthmatic

component i.e > 400 ml improvement post b-d.

• The absence of reversibility does not exclude a diagnosis of asthma:

i.e. airways remodelling in severe asthma

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

16

Lung Function Testing : Obstruction

17

Ventilation (L/min)

0 20 40 60 80 0 20 40 60 80

140

120

100

80

60

40

20

0

140

120

100

80

60

40

20

0

Vo

lum

e (%

pre

d T

LC)

Normal(n=25)

COPD(n=105)

RV

IRVIC

ICVC

Dynamic Lung Hyperinflation

O'Donnell DE, et al.: Am J Respir Crit Care Med 2001; 164(5):770-7.

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

19

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Restriction

20

Lung Function Testing : Restriction

21

O’Donnell DE, et al. Can Respir J 2007;14(Suppl B):5B-32B

COPD: Classification By SpirometryBased on Postbronchodilator FEV1

Severity of Restriction: FVC

Mild 65% to 80% predictedModerate 50% to 65% predictedSevere <50% predicted

22

Bronchoprovocation testing

Case 1

61 female smoker 40 p-y

Morning cough and white sputum x 12 months without

dyspnea

Exam normal

Measured Predicted %Pred Post

B-D

FEV1 2.9 3.0 96 3.0

FVC 3.6 3.7 97 3.7

FEV1/

FVC%

80% 80% 100

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

25

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Restriction

26

Case 2

50 male smoker 40 p-y

Cough and wheezes and dyspnea on effort x 6

months

Exam – mild wheezes

Measured Predicted %Pred Post B-D

FEV1 3.2 4.0 80 3.25

FVC 4.8 5.0 90 4.85

FEV1/

FVC%

67 80 68

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

28

Measured Predicted %Pred Post B-D

FEV1 1.9 2.8 68 1.9

FVC 3.2 3.7 86 3.4

FEV1/

FVC%

59 75 55

Case 3

66 female smoker 40 p-y

Morning cough x 5 yrs, wheezes, dyspnea

Exam –diffuse wheezes

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

30

Case 4

70 male COPD; 2 exacerbations past year requiring use

of oral steroids.

Spiriva, Serevent, Ventolin Stable

Measured Predicted %Pred Post B-D

FEV1 0.9 3.0 30 1.0

FVC 2.5 4.0 63 2.5

FEV1/

FVC%

36 75 40

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

32

Ventilation (L/min)

0 20 40 60 80 0 20 40 60 80

140

120

100

80

60

40

20

0

140

120

100

80

60

40

20

0

Vo

lum

e (%

pre

d T

LC)

Normal(n=25)

COPD(n=105)

RV

IRVIC

ICVC

Dynamic Lung Hyperinflation

O'Donnell DE, et al.: Am J Respir Crit Care Med 2001; 164(5):770-7.

EPREUVE DE FONCTIONS PULMONAIRES / PULMONARY FUNCTIONS

Division Respiratoire / Respiratory Division

PT : --------- SEX : F AGE : 71

PHYSICIAN : H. KREISMAN HT : 156.0 cm

TECH : P. KUPFER WT : 76.0 kg

Prebronchodilator Postbronchodilator

Spirometry Actual %Pred Predicted Actual %Pred %Chg

VEMS (L) 1.31 67 1.96 1.66 85 26%

CVF (L) 1.97 74 2.53 2.31 92 23%

VEMS/CVF (%) 67 89 79 72 90 2

CPT (L) 3.64 85 4.29

CRF (L) 1.80 81 2.21

VR (L) 1.54 90 1.71

Pre-Drug* Avgs

Diffusion Actual %Pred Predicted

Dsb ml/min/mmHg 22.5 133 16.9

NOTES: 2 puffs VENTOLIN, NON-SMOKER, C/) SOB & SOBOE X 3 months

Patient was on METOPROLOL for high BP, MVV = 56% PRED

0

2

4

6

8

10

-10

-2

-4

-6

-8

Flow (L/S)

Vol (L)

Pre

Post

1 2 3 4 5 6 7

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Obstruction

38

EPREUVE DE FONCTIONS PULMONAIRES / PULMONARY FUNCTIONS

Division Respiratoire / Respiratory Division

PT : --------- SEX : F AGE : 32

PHYSICIAN : COPELAND HT : 162.0 cm

TECH : MATTOSCIO WT : 66.0 kg

Pre-Drug* Post-Drug* Ventolin 200mcg

Spirometry Actual %Pred Predicted Actual %Pred %Chg

FEV1 (L) 3.52 119 2.96 3.49 118 0

FVC (L) 4.16 120 3.46 4.07 118 -2

FEV1 / FVC (%) 84 99 86 86 100 1

TLC (L) 5.32 105 5.05

FRC (L) 2.92 107 2.72

RV (L) 1.39 88 1.57

Pre-Drug* Std

Diffusion Actual %Pred Predicted

Dsb ml/min/mmHg 25.56 116 22.09

NOTES: EX-SMOKER 0.4 PPD 15 YRS or 6 PACK/YRS; C/O SOBOE, WHEEZING,

COUGH, CHEST TIGHTNESS X 6 MONTHS; MVV = 115% PRED;

0

2

4

6

8

10

-10

-2

-4

-6

-8

Flow (L/S)

Vol (L)

Pre

Post

1 2 3 4 5 6 7

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Restriction

41

CONCENTRATION MG/ML FEV1(L) %CHG

0.06

0.125 2.28 1

0.25

0.50 2.21 4

1.0

2.0 1.71 26

200 MCG VENTOLIN 2.50

EPREUVE DE FONCTIONS PULMONAIRES / PULMONARY FUNCTIONS

Division Respiratoire / Respiratory Division

PT : --------- SEX : F AGE : 52

PHYSICIAN : BARON HT : 154.0 cm

TECH : KLEBANSKYJ WT : 62.0 kg

Pre-Drug* Post-Drug* Ventolin 200mcg

Spirometry Actual %Pred Predicted Actual %Pred %Chg

FEV1 (L) 1.77 77 2.31 1.71 74 -3

FVC (L) 1.86 67 2.77 1.82 66 -2

FEV1 / FVC (%) 95 115 83 94 113 -1

TLC (L) 2.57 60 4.26

FRC (L) 1.44 61 2.37

RV (L) 0.81 54 1.50

Pre-Drug* Avg

Diffusion Actual %Pred Predicted

Dsb ml/min/mmHg 8.63 46 18.85

NOTES: C/O SOBOE X 6 MONTHS; MVV = 135% PRED; PT HAD DIFFICULTY

PERFORMING FVL & SVC

Lowry JB, A Primary Care Physician primer on Spirometry

Diagnostic Flow Diagram For

Restriction

44

0

2

4

6

8

10

-10

-2

-4

-6

-8

Flow (L/S)

Vol (L)

Pre

Post

1 2 3 4 5 6 7

Other spirometric diagnoses

40 y.o. male

Obese

SOB

Daytime Sleepiness

Lack of concentration

Snores

0

2

4

6

8

10

-10

-2

-4

-6

-8

Flow (L/S)

Vol (L)

Pre

Post

1 2 3 4 5 6 7

All that wheezes is not asthma

52 year old female

Intubation 2 weeks for respiratory failure

Increasing SOB and wheezes 2 months post

discharge from ICU

“Blue” and “orange” pumps don t help

0

2

4

6

8

10

-10

-2

-4

-6

-8

Flow (L/S)

Vol (L)

Pre

Post

1 2 3 4 5 6 7

Tracheal Stenosis

Conclusions

Spirometry is a necessary tool for diagnosis and

evaluation of many respiratory diseases including

common diseases such as asthma and COPD.

Spirometry does require some issues of quality

control.

Categorization of obstructive vs restrictive

disorders is fairly easy and can be performed

looking at 3 parameters: FEV1/FVC, FEV1,

FVC.