Spirometry. Sonia Munde. Senior Respiratory Care Physiologist Adult Respiratory Care & Rehab Team Barts Health

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1 Spirometry Sonia Munde Senior Respiratory Care Physiologist Adult Respiratory Care & Rehab Team Barts Health

2 COPD Definition.airflow obstruction is usually progressive, not fully reversible and does not change markedly over several months. The disease is predominantly caused by smoking. NICE 2010

3 Asthma Definition.in susceptible individuals, inflammatory symptoms are usually associated with widespread but variable airflow obstruction and an increase in airway response to a variety of stimuli. Obstruction is often reversible, either spontaneously or with treatment. BTS and SIGN 2003

4 Spirometry Spirometry is a method of assessing lung function by measuring the volume of air the patient is able to expel out from the lungs after maximal inspiration ( FEV1, FVC and FEV1/FVC) And also on a slow effort ( SVC and FEV1/SVC)

5 Spirometry is a reliable method of identifying Obstructive illness i.e. chronic obstructive pulmonary disease Reversible disease I.e. Asthma Restrictive disease i.e. Pulmonary fibrosis It can be used to grade the severity of COPD

6 Diagnosing COPD At the time of their initial diagnostic evaluation in addition to spirometry all patients should have: CXR- Chest X ray FBC- Full Blood Count BMI- Body Mass Index

7 Additional Investigations CT Scan ECG Echo Pulse Oximetry Sputum Culture Transfer factor for carbon monoxide (TLCO) Serial Domiciliary Peak Flows Alpha-1-antitrypsin

8 Spirometry measurements FEV1 - The volume of air that the patient is able to breathe out in the first second of forced expiration FVC - The total volume of air that the patient can exhale forcibly in one breathe FEV1 / FVC - The ratio is expressed as a percentage Peak Flow - The flow rate SVC The total amount of air the patient can exhale slowly on one breath

9 Indices Measured

10 Before performing Spirometry The patient, ideally, should - Avoid alcohol for at least 4 hours - Avoid eating a substantial meal - Wear loose fitting clothing If Reversibility is to be performed - - Avoid taking short acting bronchodilators for at least 4 hours prior to testing - Avoid smoking for 1 hour prior to testing -Be Well!!

11 Spirometry Contraindications Haemoptysis of unknown origin Pneumothorax (Need confirmation of resolution) Unstable cardiovascular status Myocardial Infarction (Last 3 months) Thoracic, abdominal or cerebral aneurysms

12 Spirometry Contraindications Recent Eye surgery (3 months) Recent thoracic or abdominal surgery (3 months) Pregnancy (1 st Trimester contraindicated but in 2 nd and 3 rd Trimester results may be effected by uterus size)

13 Relaxed Vital Capacity(SVC) Take as large a breath of air in as possible Pinch your nose or attach a nose clip to prevent air leakage Put the filter into your mouth ensuring that there are no leaks at the sides of your mouth Breathe out for as long as possible. This breath should be in your own time and should not be forced

14 Relaxed Vital Capacity (SVC) Performed due to collapsing alveoli in some patients during Forced Vital Capacity technique This technique would usually be performed before the Forced Vital Capacity readings The reading is sometimes referred to as VC, EVC or RVC Minimum of three readings taken 3 best results should be within 150mls of each other

15 Forced Vital Capacity (FVC) Take as large a breath of air in as possible Put the filter into your mouth ensuring there are no leaks at the side of your mouth Pinch your nose or attach a nose clip to prevent air leakage Blast as quickly as possible and for as long as possible

16 Forced Vital Capacity (FVC) A minimum of three readings should be taken There should be less than 5% or 150mls variance between the best results The technique should be repeated until this is achieved or the patient is exhausted and can no longer perform the technique Time should be given to the patient to recover between readings

17 Spirometry Interpretation

18 Correction Factors M A K E S U R E Y O U H A V E E N T E R E D T H E C O R R E C T H E I G H T, G E N D E R, A G E A N D E T H N I C I T Y BTS Guidelines Only Ethnic Origin Correction Factor Caucasian 100% Afro-Caribbean Reduce by 13% (87%) Asian Reduce by 10% (90%)

19 Accurate Interpretation Use Best Test (Less than 5% Variance from next best) Best Test FVC, FEV1 or FVC & FEV1 If spirometer selects best test, CHECK Minimum number of tests 3 Curve shape effort, cough, extra breath etc Relaxed Expiratory Vital Capacity (EVC) recorded and used when better than FVC Accurate height Correction Factors

20 Normal Spirometry results FEV1/FVC ratio greater than 70%- means NO airway obstruction present FEV1 > 80% predicted FVC > 80% predicted

21 47 years old Case Study 1 Smoked 30 cigarettes a day since he was 15 years old Painter and decorator Repeated chest infections every year Finding it difficult to climb ladders and walk up steep hills Chronic Productive Cough

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23 Spirometry shows Obstruction FEV1/FVC Ratio <70% less than or equal to 70% = obstruction present Than check FEV1 classification Mild 80% equal to or greater Moderate 50-79% Severe 30-49% Very Severe 30% or less FVC should be normal at > 80% predicted

24 Examples Obstructive Disorders COPD Asthma Bronchiectasis Tumour Foreign Body Important to match clinical history and symptom profile before making a formal diagnosis

25 NICE 2010 Consider alternative diagnoses in: Older people without typical symptoms of COPD where the FEV1/FVC is <0.7 Younger people with symptoms of COPD where the FEV1/FVC ration is 0.7

26 Severity of Obstruction NICE Guideline (2004) ATS/ERS (2004) GOLD (2008) NICE Guideline (2010) Post- Bronchodilato r FEV1/FVC FEV1 % Predicted Severity of Airflow Obstruction Post - Bronchodilator Post - Bronchodilator Post - Bronchodilator <0.7 80% Mild Stage 1-Mild Stage 1-Mild* < % Mild Moderate Stage 2- Moderate Stage 2- Moderate < % Moderate Severe Stage 3-Severe Stage 3-Severe <0.7 < 30% Severe Very Severe Stage 4-Very Severe** Stage 4-Very Severe** *Symptoms should be present to diagnose COPD with mild airflow obstruction **or FEV1 <50% with respiratory failure

27 Case Study 2 35 years old Teacher 20 pack year history of smoking Breathless in the last 6 months Breathless on exertion and has to stop if walking fast None productive cough

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29 Spirometry shows Restriction FEV1 less than 80% predicted (60%) FVC less than 80% predicted (49%) FEV1/FVC Ratio >70% (96.6%)

30 Examples of Restrictive Disorders Kyphoscoliosis Muscular Dystrophy Problems Arthritis Pleural Problems Interstitial Lung Disease Obesity Drugs

31 Spirometry that shows a Mixed/combined results FEV1 usually less than 80% predicted FVC less than 80% predicted FEV1/FVC ratio is also less than 70% Unlike restrictive pattern when ratio is greater than 70% predicted

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33 Examples Combined Disorders Severe COPD Multiple Pathology e.g. Kyphscoliosis and COPD Tumour and COPD

34 Why Annual FEV1? Used to detect sudden deterioration in lung function Should precipitate action if deterioration marked. Normal deterioration in FEV1 thought to be 50ml/annum in none smoking individual

35 Asthma Or COPD?

36 COPD Definition.airflow obstruction is usually progressive, not fully reversible and does not change markedly over several months. The disease is predominantly caused by smoking. NICE 2010

37 Asthma Definition.in susceptible individuals, inflammatory symptoms are usually associated with widespread but variable airflow obstruction and an increase in airway response to a variety of stimuli. Obstruction is often reversible, either spontaneously or with treatment. BTS and SIGN 2003

38 Post Bronchodilator Spirometry QOF 12 states that a diagnosis of COPD should be confirmed by recording post bronchodilator spirometry Bronchodilator should be taken 20 minutes prior to spirometry being performed i.e. 4 puffs Salbutamol 100mcg MDI with an spacer device or Salbutamol 2.5mg/ 5.0mg nebulised

39 Post Bronchodilator Spirometry Why? Post Bronchodilator recommended by GOLD and used in new trials e.g. UPLIFT Removes conflict with many guidelines Decrease work load in primary care Failure to use post bronchodilator over estimates COPD by 25% DOH 2009

40 Post Bronchodilator Spirometry Why Not Reversibility? Repeated FEV1 measurements can show small spontaneous fluctuations The results of a reversibility test performed on different occasions can be inconsistent and not reproducible Over-reliance on a single reversibility test may be misleading unless the change in FEV1 is greater than 400 ml The definition of the magnitude of a significant change is purely arbitrary Response to long-term therapy is not predicted by acute reversibility testing. NICE 2010

41 Diagnosing COPD COPD Asthma Smoker or ex-smoker Nearly all Possibly Symptoms under the age 35 Rare Often Chronic Productive Cough Common Uncommon Breathlessness Night time waking with breathlessness and or wheeze Present and progressive Uncommon Variable Common Significant diurnal or day to day variability of symptoms Uncommon Common

42 Smoking History Cigarettes per Day x Years Smoked = 1 pack Year 20 e.g. 1 Pack Year = 20 cigarettes/day for 1 year or; 10 cigarettes/day for 2 years 40 cigarettes a day for 6 months 50g/2oz tobacco Cigars Café Crème Hamlet Corona = 100 cigarettes = 3 cigarettes = 5 cigarettes = 8+ cigarettes 20 pack years is considered a significant factor for developing COPD

43 Reversibility Useful if diagnosis is not clear One off spirometry does not EXCLUDE the diagnosis of Asthma Either; Measure peak flows for 14 days morning and evening. Diurnal variation of greater than 20% indicates asthma Record pre and post bronchodilator spirometry

44 Understanding Reversibility An FEV1 that increases by < 400mls is likely to have COPD An FEV1 that increases by > 400mls is likely to have asthma However if; FEV1 < 80% Ratio < 70% Post > 400mls Obstruction is not fully reversible

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46 Spirometry results show Obstruction FEV1/FVC ratio = 39% FEV1 % predicted = 56% FVC % predicted = 115 % Classification of obstruction Moderate airway obstruction

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48 Spirometry results show Obstruction FEV1 /FVC ratio = 44% FEV1 % predicted = 76% FVC % predicted= 146% Classification FEV1 predicted 76% = Moderate airway obstruction, with a large FVC,? hyperinflation

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50 Spirometry results show Obstruction FEV1/FVC ratio = 50% FEV1 % predicted = 81% FVC % predicted = 128% Classification FEV1 = 81% therefore Mild airway obstruction

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52 Spirometry Results show Obstruction FEV1/FVC ratio = 65% FEV1 % predicted = 68% FVC % predicted = 86% Classification FEV1 % predicted= 68% therefore moderate airway obstruction

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54 Spirometry results show Obstruction FEV1/FVC ratio = 72% FEV1 % predicted = 101% (2.05L) SVC % predicted = 122% ( 2.92L) FVC % predicted = 117% (2.84L) Normal spirometry however the SVC larger than FVC therefore the true FEV1/FVC ratio is 70% FEV1 (2.05L) divide by SVC (2.92L) = 70% ratio Therefore mild airway obstruction

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56 Spirometry results show Pre inhaler spirometry shows FEV1/FVC ratio = 57% FEV1 % predicted = 50% FVC % predicted = 69% FEV1= 1.54L or 1540ml Post inhaler spirometry results FEV1/FVC ratio= 81% FEV1 % predicted= 67% FVC % predicted = 85% FEV1 = 2.06L or 2060ml Pre to post inhaler greater than a 400ml change in FEV1 Pre inhaler mixed/combined pattern spirometry Post inhaler moderate airway obstruction with significant response to Salbutamol

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58 Spirometry results show Pre inhaler spirometry shows FEV1/FVC ratio = 36% FEV1 % predicted = 38% FVC % predicted = 88% FEV1= 0.80L or 800ml Post inhaler spirometry results FEV1/FVC ratio= 49% FEV1 % predicted= 51% FVC % predicted = 114% FEV1 = 1.07L or 1760ml Pre to post inhaler less than a 400ml change in FEV1 Pre inhaler severe airway obstruction Post inhaler moderate airway obstruction with NO significant response to Salbutamol

59 Questions

60 References SPIROMETRY IN PRACTICE A PRACTICAL GUIDE TO USING SPIROMETRY IN PRIMARY CARE 2 ND Edition BTS _practice051.pdf NICE Guidelines for chronic obstructive pulmonary disease (2010) GENERAL CONSIDERATIONS FOR LUNG FUNCTION TESTING ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING European Respiratory Journal STANDARDISATION OF SPIROMETRY ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING European Respiratory Journal

61 References SPIROMETRY IN PRACTICE A PRACTICAL GUIDE TO USING SPIROMETRY IN PRIMARY CARE 2 ND Edition BTS _practice051.pdf GENERAL CONSIDERATIONS FOR LUNG FUNCTION TESTING ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING European Respiratory Journal STANDARDISATION OF SPIROMETRY ATS/ERS TASK FORCE: STANDARDISATION OF LUNG FUNCTION TESTING European Respiratory Journal