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How to…… Diagnose earlier and accurately: spirometry and history taking

Chris Loveridge Respiratory Practice Nurse

Spirometry Clinical Lead

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Importance of History

95%

5%

History

Spirometry

3

0

Chronic obstructive

pulmonary disease

Implementing NICE guidance

June 2010

NICE clinical guideline 101

Definition of COPD

• Airflow obstruction is defined as reduced FEV1/FVC ratio (< 0.7)

• It is no longer necessary to have an FEV1 < 80% predicted for definition of airflow obstruction

• If FEV1 is ≥ 80% predicted, a diagnosis of COPD should only be made in the presence of respiratory symptoms, for example breathlessness or cough

FEV1 = forced expiratory volume in 1 second FVC = forced vital capacity

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Diagnose COPD: 3

• Assess severity of airflow obstruction using reduction in FEV1

NICE clinical guideline 12

(2004)

ATS/ERS 2004 GOLD 2008 NICE clinical guideline 101

(2010)

Post-bronchodilator

FEV1/FVC

FEV1 % predicted

Post-bronchodilator

Post-bronchodilator

Post-bronchodilator

< 0.7 80% Mild Stage 1 (mild) Stage 1 (mild)*

< 0.7 50–79% Mild Moderate Stage 2 (moderate)

Stage 2 (moderate)

< 0.7 30–49% 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 in people with mild airflow

obstruction

** Or FEV1 < 50% with respiratory failure

[new 2010]

Diagnose COPD

Consider a diagnosis of COPD for people who are:

– over 35, and

– smokers or ex-smokers, and

– have any of these symptoms:

- exertional breathlessness

- chronic cough

- regular sputum production,

- frequent winter ‘bronchitis’

- wheeze

[2004]

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Diagnose COPD: 2

– The presence of airflow obstruction should be confirmed by performing post-bronchodilator spirometry [new 2010]

– All health professionals involved in the care of people with COPD should have access to spirometry and be competent in

the interpretation of the results [2004]

Spectrum of COPD Screening, Detection and Diagnosis

Well At-risk With COPD diagnosis

No symptoms Symptoms but

no diagnosis

MILD

stage

MODERATE

stage

SEVERE

stage

The earliest point at

which airflow

obstruction may be

detected by

spirometry

Damage

Unaware of

lung health

Aware of

lung health

‘Upper

limits of

normal’

‘Lower

limits of

normal’

VERY SEVERE

stage

•Improve Diagnostic accuracy

•Implement case finding strategies

•Consider the case for screening

•Identify those with A1AT deficiency

•Establish accurate disease registers

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Recommendation 8: A diagnosis of COPD should be confirmed by quality assured spirometry and other investigations appropriate to the individual. Recommendation 8: A diagnosis of COPD should be confirmed by quality assured spirometry and other investigations appropriate to the individual.

Identification and diagnosis

Standards for spirometry in primary care.

The spirometer must be able to record FEV1, FVC, FEV1/FVC ratio, and display a graph of volume against time

The spirometrist must be trained in the use of the spirometer and in assessing technical adequacy of readings

The patient should be prepared, including written advice on stopping bronchodilators in advance of reversibility testing

Levy et al. Prim Care Respir J 2009; 18,:130-147

What is quality spirometry?

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Quality assurance

The curve must be smooth, upward and free of irregularities

The curve must reach a plateau

Almost vertical rise to PEF

‘Sharp’ point at PEF

Trace free of irregularities

Trace ‘merges’ with horizontal axis

Volume/Time Trace Flow/Volume Trace

Spirometry patterns

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Spirometry patterns - flow/volume

Peak expiratory flow

Volume (litres

Volume (litres Volume (litres

Volume (litres

FVC

Peak expiratory flow

Predicted normal curve

Predicted normal curve

So spirometry....top ten tips

• Patient demographics

• Technical acceptability of blows

• Number of blows performed

• Quality of blows

• Reproducibility/repeatability

• Measuring airflow obstruction

• Severity of airflow obstruction

• Limitations of machine interpretation

• Reversibility

• Supports history/fits clinical presentation

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Quality Assured Diagnostic Spirometry

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Repeatability/Reproducibility

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QUESTIONS ?

Thank you