1. Spirometry in Primary Care
Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2010

2. Spirometry - Introduction
Spirometry is the gold standard for COPD diagnosis
Underuse leads to inaccurate COPD diagnosis
Widespread uptake has been limited by:
Concerns over technical performance of operators
Difficulty with interpretation of results
Lack of approved local training courses
Lack of evidence showing clear benefit when spirometry is incorporated into management

3. What is Spirometry?
Spirometry is a method of assessing lung function by measuring the total volume of air the patient can expel from the lungs after a maximal inhalation.

4. Why Perform Spirometry?
Measure airflow obstruction to help make a definitive diagnosis of COPD
Confirm presence of airway obstruction
Assess severity of airflow obstruction in COPD
Detect airflow obstruction in smokers who may have few or no symptoms
Monitor disease progression in COPD
Assess one aspect of response to therapy
Assess prognosis (FEV1) in COPD
Perform pre-operative assessment

5. Spirometry – Additional Uses
Make a diagnosis and assess severity in a range of other respiratory conditions
Distinguish between obstruction and restriction as causes of breathlessness
Screen workforces in occupational environments
Assess fitness to dive
Perform pre-employment screening in certain professions

6. Types of Spirometers Bellows spirometers:
Measure volume; mainly in lung function units
Electronic desk top spirometers:
Measure flow and volume with real time display
Small hand-held spirometers:
Inexpensive and quick to use but no print out

7. Volume Measuring Spirometer

8. Flow Measuring Spirometer

9. Desktop Electronic Spirometers

10. Small Hand-held Spirometers

11. Standard Spirometric Indicies
FEV1 - Forced expiratory volume in one second:
The volume of air expired in the first second of the blow
FVC - Forced vital capacity:
The total volume of air that can be forcibly exhaled in one breath
FEV1/FVC ratio:
The fraction of air exhaled in the first second relative to the total volume exhaled

12. Additional Spirometric Indicies
VC - Vital capacity:
A volume of a full breath exhaled in the patient’s own time and not forced. Often slightly greater than the FVC, particularly in COPD
FEV6 – Forced expired volume in six seconds:
Often approximates the FVC. Easier to perform in older and COPD patients but role in COPD diagnosis remains under investigation
MEFR – Mid-expiratory flow rates:
Derived from the mid portion of the flow volume curve but is not useful for COPD diagnosis

13. Lung Volume Terminology
Inspiratory reserve
volume
Inspiratory
capacity
Total
lung
capacity
Tidal volume
Expiratory reserve
volume
Vital
capacity
Residual volume

14. Spirogram Patterns Normal Obstructive Restrictive
Mixed Obstructive and Restrictive

15. Spirometry Predicted Normal Values

16. Predicted Normal Values
Affected by:
Age
Height
Sex
Ethnic Origin

17. Criteria for Normal Post-bronchodilator Spirometry
FEV1: % predicted > 80%
FVC: % predicted > 80%
FEV1/FVC: > , depending on age

18. Normal Trace Showing FEV1 and FVC5 4
FEV1 = 4L
FVC = 5L
FEV1/FVC = 0.8
Volume, liters 3 2 1 1 1 2 3 4 5 6
Time, sec

19. SPIROMETRY
OBSTRUCTIVE DISEASE

20. Spirometry: Obstructive Disease
Normal 5 4 3
Volume, liters
FEV1 = 1.8L
FVC = 3.2L
FEV1/FVC = 0.56 2
Obstructive 1 1 2 3 4 5 6
Time, seconds

21. Diseases Associated With Airflow Obstruction
COPD
Asthma
Bronchiectasis
Cystic Fibrosis
Post-tuberculosis
Lung cancer (greater risk in COPD)
Obliterative Bronchiolitis

22. Spirometric Diagnosis of COPD
COPD is confirmed by post–bronchodilator FEV1/FVC < 0.7
Post-bronchodilator FEV1/FVC measured 15 minutes after 400µg salbutamol or equivalent

23. Bronchodilator Reversibility Testing
Provides the best achievable FEV1 (and FVC)
Helps to differentiate COPD from asthma
Must be interpreted with clinical history - neither asthma nor COPD are diagnosed on spirometry alone

24. Bronchodilator Reversibility Testing
Can be done on first visit if no diagnosis has been made
Best done as a planned procedure: pre- and post-bronchodilator tests require a minimum of 15 minutes
Post-bronchodilator only saves time but does not help confirm if asthma is present
Short-acting bronchodilators need to be withheld for at least 4 hours prior to test

25. Bronchodilator Reversibility Testing
Dose
FEV1 before and after
Salbutamol
200 – 400 µg via large volume spacer
15 minutes
Terbutaline
500 µg via Turbohaler®
Ipratropium
160 µg** via spacer
45 minutes
* Some guidelines suggest nebulised bronchodilators can be given but the doses are not standardised. “There is no consensus on the drug, dose or mode of administering a bronchodilator in the laboratory.” Ref: ATS/ERS Task Force : Interpretive strategies for Lung Function Tests ERJ 2005;26:948
** Usually 8 puffs of 20 µg

26. Figure 5.1-6. Bronchodilator Reversibility Testing in COPD
GOLD Report (2009)

27. Figure 5.1-6. Bronchodilator Reversibility Testing in COPD
Preparation
Tests should be performed when patients are clinically stable and free from respiratory infection
Patients should not have taken:
inhaled short-acting bronchodilators in the previous six hours
long-acting bronchodilator in the previous 12 hours
sustained-release theophylline in the previous 24 hours

28. Figure 5.1-6. Bronchodilator Reversibility Testing in COPD
Spirometry
FEV1 should be measured (minimum twice, within 5% or 150mls) before a bronchodilator is given
The bronchodilator should be given by metered dose inhaler through a spacer device or by nebulizer to be certain it has been inhaled
The bronchodilator dose should be selected to be high on the dose/response curve
(…..continued)

29. Figure 5.1-6. Bronchodilator Reversibility Testing in COPD
Spirometry (continued)
Possible dosage protocols:
400 µg β2-agonist, or
µg anticholinergic, or
the two combined
FEV1 should be measured again:
15 minutes after a short-acting bronchodilator
45 minutes after the combination

30. Figure 5.1-6. Bronchodilator Reversibility Testing in COPD
Results
An increase in FEV1 that is both greater than 200 ml and 12% above the pre- bronchodilator FEV1 (baseline value) is considered significant
It is usually helpful to report the absolute change (in ml) as well as the % change from baseline to set the improvement in a clinical context

31. SPIROMETRY
RESTRICTIVE DISEASE

32. Criteria: Restrictive Disease
FEV1: normal or mildly reduced
FVC: < 80% predicted
FEV1/FVC: > 0.7

33. Spirometry: Restrictive Disease
Normal 5 4 3
Volume, liters
Restrictive
FEV1 = 1.9L
FVC = 2.0L
FEV1/FVC = 0.95 2 1 1 2 3 4 5 6
Time, seconds

34. Diseases Associated with a Restrictive Defect
Pulmonary
Fibrosing lung diseases
Pneumoconioses
Pulmonary edema
Parenchymal lung tumors
Lobectomy or pneumonectomy
Extrapulmonary
Thoracic cage deformity
Obesity
Pregnancy
Neuromuscular disorders
Fibrothorax

35. Mixed Obstructive/Restrictive
FEV1: < 80% predicted
FVC: < 80% predicted
FEV1 /FVC: < 0.7

36. Mixed Obstructive and Restrictive
Normal
Volume, liters
FEV1 = 0.5L
FVC = 1.5L
FEV1/FVC = 0.30
Obstructive - Restrictive
Time, seconds
Restrictive and mixed obstructive-restrictive are difficult to diagnose by spirometry alone; full respiratory function tests are usually required
(e.g., body plethysmography, etc)

37. SPIROMETRY
Flow Volume

38. Flow Volume Curve Standard on most desk-top spirometers
Adds more information than volume time curve
Less understood but not too difficult to interpret
Better at demonstrating mild airflow obstruction

39. Flow Volume Curve Maximum expiratory flow (PEF) FVC Volume (L)
Expiratory flow rate
L/sec
FVC RV
TLC
Inspiratory flow rate
L/sec
Volume (L)

40. Flow Volume Curve Patterns Obstructive and Restrictive
Severe obstructive
Restrictive
Expiratory flow rate
Expiratory flow rate
Expiratory flow rate
Volume (L)
Volume (L)
Volume (L)
Reduced peak flow, scooped out mid-curve
Steeple pattern, reduced peak flow, rapid fall off
Normal shape, normal peak flow, reduced volume

41. Spirometry: Abnormal Patterns
Obstructive
Restrictive
Mixed
Volume
Volume
Volume
Time
Time
Time
Slow rise, reduced volume expired; prolonged time to full expiration
Fast rise to plateau at reduced maximum volume
Slow rise to reduced maximum volume; measure static lung volumes and full PFT’s to confirm

42. Performing Spirometry
PRACTICAL SESSION
Performing Spirometry

43. Spirometry Training
Training is essential for operators to learn correct performance and interpretation of results
Training for competent performance of spirometry requires a minimum of 3 hours
Acquiring good spirometry performance and interpretation skills requires practice, evaluation, and review
Spirometry performance (who, when and where) should be adapted to local needs and resources
Training for spirometry should be evaluated

44. Obtaining Predicted Values
Independent of the type of spirometer
Choose values that best represent the
tested population
Check for appropriateness if built into
the spirometer
Optimally, subjects should rest 10 minutes
before performing spirometry

45. Withholding Medications
Before performing spirometry, withhold:
Short acting β2-agonists for 6 hours
Long acting β2-agonists for 12 hours
Ipratropium for 6 hours
Tiotropium for 24 hours
Optimally, subjects should avoid caffeine and cigarette smoking for 30 minutes before performing spirometry

46. Performing Spirometry - Preparation
Explain the purpose of the test and demonstrate the procedure
Record the patient’s age, height and gender and enter on the spirometer
Note when bronchodilator was last used
Have the patient sitting comfortably
Loosen any tight clothing
Empty the bladder beforehand if needed

47. Performing Spirometry
Breath in until the lungs are full
Hold the breath and seal the lips tightly around a clean mouthpiece
Blast the air out as forcibly and fast as possible. Provide lots of encouragement!
Continue blowing until the lungs feel empty

48. Performing Spirometry
Watch the patient during the blow to assure the lips are sealed around the mouthpiece
Check to determine if an adequate trace has been achieved
Repeat the procedure at least twice more until ideally 3 readings within 100 ml or 5% of each other are obtained

49. Reproducibility - Quality of Results
Volume, liters
Time, seconds
Three times FVC within 5% or 0.15 litre (150 ml)

50. Spirometry - Possible Side Effects
Feeling light-headed
Headache
Getting red in the face
Fainting: reduced venous return or vasovagal attack (reflex)
Transient urinary incontinence
Spirometry should be avoided after recent heart attack or stroke

51. Spirometry - Quality Control
Most common cause of inconsistent readings is poor patient technique
Sub-optimal inspiration
Sub-maximal expiratory effort
Delay in forced expiration
Shortened expiratory time
Air leak around the mouthpiece
Subjects must be observed and encouraged throughout the procedure

52. Spirometry – Common Problems
Inadequate or incomplete blow
Lack of blast effort during exhalation
Slow start to maximal effort
Lips not sealed around mouthpiece
Coughing during the blow
Extra breath during the blow
Glottic closure or obstruction of mouthpiece
by tongue or teeth
Poor posture – leaning forwards

53. Equipment Maintenance
Most spirometers need regular calibration to check accuracy
Calibration is normally performed with a 3 litre syringe
Some electronic spirometers do not require daily/weekly calibration
Good equipment cleanliness and anti-infection control are important; check instruction manual
Spirometers should be regularly serviced; check manufacturer’s recommendations

54. Examples - Unacceptable Traces
Troubleshooting
Examples - Unacceptable Traces

55. Unacceptable Trace - Poor Effort
Normal
Volume, liters
Variable expiratory effort
Inadequate sustaining of effort
May be accompanied by a slow start
Time, seconds

56. Unacceptable Trace – Stop Early
Normal
Volume, liters
Time, seconds

57. Unacceptable Trace – Slow Start
Normal
Volume, liters
Time, seconds

58. Unacceptable Trace - Coughing
Normal
Volume, liters
Time, seconds

59. Unacceptable Trace – Extra Breath
Normal
Volume, liters
Time, seconds

60. Some Spirometry Resources
Global Initiative for Chronic Obstructive Lung Disease (GOLD) -
Spirometry in Practice -
ATS-ERS Taskforce: Standardization of Spirometry. ERJ 2005;29:
National Asthma Council: Spirometry Handbook