Diagnosis of chronic obstructive pulmonary disease based on NICE Draft for Consultation July 2018. NICE suggests that diagnosis is suspected on the basis of symptoms and signs and is supported by Spirometry.Person over 35 who is a current or an ex smoker and has one or more of-exertional breathlessness chronic cough regular sputum frequent winter bronchitis wheeze .Also check for these to r/o other causes of breathlessness – particularly CVD.weight loss reduced exercise tolerance waking at night with breathlessness ankle swelling fatigue occupational hazards chest pain haemoptysis.Assess breathlessness – NICE recommends using the Medical Research Council ( MRC ) dyspnoe scale according to level of exertion required to elicit it as one of the primary symptoms of COPD is breathlessness.
Spirometry-Perform on diagnosis or to reconsider diagnosis for people who show and exceptionally good response.Change for 2018 is the indication for spirometry to monitor disease progression.Measure post-bronchidilator to confirm diagnosis Older people with FEv1 / FVC below 0.7 but no typical symptoms of COPD- consider an alternative diagnosis – investigate further Younger people who have symptoms of COPD with FEV1 / FVC ratio above 0.7 – consider COPD diagnosis NICE by stating above is advising not to rely solely on spirometry readings alone in diagnosing or ruling out COPD NICE also emphasizes that spirometry should be available , we should be able to interpret it , adequate training should be provided and quality control processes should be in place
Further Investigations-CXR FBC ( anaemia and polycythemia ) BMI-sputum culture if sputum persistently present and is purulent serial home peak flow ( r/o asthma ) ECG and BNP ( r/o CVD ) Echocardiogram – r/o cardiac disease and pul hypertension CT scan of thorax ○ investigate symptoms which are disproportionate to spirometry findings ○ r/o other lung conditions as fibrosis or bronchiectasis ○ investigate abnormal CXR findings ○ assess suitability for lung volume reduction procedures Serum alpha- 1 anti-trypsin – consider checking ○ early onset ○ minimal smoking history or family history TLCO ( Transfer factor for carbon monoxide ) ○ if symptoms disproportionate to spirometry impairment ○ assess suitability for lung volume reduction procedures
Reversibility testing-NICE is discouraging reversibility testing and has given reasons to explain . It says that for most people routine spirometric reversibility testing is not necessary as part of the diagnostic process or to plan initial therapy with bronchodilators or corticosteroids.The draft goes on to say that this can actually be unhelpful or misleading because repeated FEV1 measurements can show small spontaneous fluctuations 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 > 400 mls 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 states that untreated COPD and asthma are frequently distinguishable on the basis of history and examination. Use the below mentioned points to help differentiate.Clinically significant COPD is not present if the FEV1 and FEV1 / FVC ratio return to normal with drug therapy.Referral for more detailed investigations including imaging and TLCO measurement Reconsider the diagnosis of COPD who report a marked improvement in symptoms in response to inhaled therapy
Incidental findings- NICE has provided some very useful recommendations on incidental findings. NICE mentions that CT scan and CXRs are accurate tests for identifying people who would test + ve for COPD using spirometry , including people without symptoms. But , some of CT and CXR techniques used in studies are not routinely used in UK clinical practice so it was unable to to make a wider recommendation on using CT scans and CXRs for diagnosing COPD.CT or CXR shows emphysema or signs of chronic airway disease.Consider primary care respiratory review and spirometry.Current smoker and spirometry results are normal & they have no symptoms or signs of respiratory disease.offer smoking cessation adv & Rx and referral to specialist stop smoking services warn them that they are at higher risk of lung disease adv to return if they develop respiratory symptoms be aware that the presence of emphysema on a CT scan is an independent risk factor for lung cancer
Not a current smoker , spirometry is normal and they have no symptoms or signs of respiratory disease.check for personal or family h/o lung or liver disease and consider alternative diagnosis such as alpha-1 anti-trypsin deficiency reassure that their emphysema or chronic airway disease is unlikely to get worse adv them to return if they develop respiratory symptoms
References National Institute for Health and Care Excellence Guideline Chronic Obstructive pulmonary disease in over 16s : diagnosis and management Draft for consultation , July 2018 MRC scale from https://www.blf.org.uk/support- for-you/breathlessness/diagnosis NICE pathways- Diagnosing and assessing COPD