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Case based discussion of COPD guidelines 2004. Diagnosis Dr Anne McGown Mar 2008. Case 1. Mrs J.W Aged 81 complaining about SOB on 50-100yards SOB 1 flight of stairs no cough or sputum no antibiotics for chest Hypertension, no IHD, no childhood asthma.
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Case based discussion of COPD guidelines 2004 Diagnosis Dr Anne McGown Mar 2008
Case 1 • Mrs J.W • Aged 81 • complaining about SOB on 50-100yards • SOB 1 flight of stairs • no cough or sputum • no antibiotics for chest • Hypertension, no IHD, no childhood asthma
What associated symptoms/factors should you ask about • Weight loss • waking at night • ankle swelling • fatigue • occupational hazards • chest pain* • haemoptysis*
MRC Dyspnoea scale • 1 Not troubled by breathlessness except on strenuous exercise • 2 Short of breath when hurrying or walking up a slight hill • 3 Walks slower than contemporaries on level ground because of breathlessness, or has to stop for breath when walking at own pace • 4 Stops for breath after walking about 100m or after a few minutes on level ground • 5 Too breathless to leave the house, or breathless when dressing or undressing
SH • Lives alone • Ex-waitress/barmaid • gave up smoking aged 65, started in her teens and smoked 10/day = 25 pack years
TH • Eprosartan • Aspirin • Omacor • bendrofluazide • doxazosin • serevent
Examination • No clubbing or oedema • pulse 72 and regular • heart sounds normal • chest clear • CXR - NAD • FEV1 1.13 53% pred • FVC 1.5l 64% pred, ratio FEV1/FVC 74%
Differential diagnosis? • Respiratory - asthma/COPD • Cardiac • Anaemia • Other rare
Main differential • Asthma • COPD • Peak flow chart no variation • Mild COPD • Improved with addition of tiotropium (could walk and talk at the same time which was what she wanted) • Discharged.
Spirometry • (a) - normal • (b) - obstructive • dashed - asthma after bronchodilator • (c) - restrictive compared to normal • From Johns Pocket Guide to Spirometry
Spirometry • Airflow obstruction if FEV1/FVC <0.7 • FEV1<80% predicted • Severity of airflow obstruction • mild - FEV1 50-80% predicted • moderate - FEV1 30-49% predicted • severe - FEV1 <30% predicted • spirometry predicts prognosis in COPD, but not disability or quality of life
Spirometry in COPD • COPD definition - presence of airflow limitation that is not fully reversible and does not change markedly over several months. • Distinguish from asthma on basis of history, examination, longitudinal observation (+/- reversibility testing and PEFR charts). • Chest pain and haemoptysis, or disproportionate SOB/cyanosis in mild cases - look for alternative diagnosis
Spirometry in COPD • The pitfalls (a) normal • (b) obstructive • From Johns Pocket Guide to Spirometry
Flow volume loops • (a) Normal • (b) - asthma • (c) - emphysema • (d) - restrictive • (e) - upper airway obstruction
Spirometry summary • Obstructive useful • May miss diagnosis if technique poor or severe disease • Restrictive less useful as more sensitive to technique, and cannot distinguish intrinsic lung disease from extrinsic lung disease (esp. obesity also chest wall, muscle)
Spirometry does not predict disability • Other prognostic factors • Frequency of exacerbation • FEV1 and TLCO • MRC breathlessness • Health status • Exercise capacity • BMI • Arterial pO2 • Cor pulmonale
Case 2 • Mr CG • Age 66 • Admitted acutely SOB • No chest pain or palpitations • History of wheeze with chest infections for several years • Ex smoker
Examination findings • Tachypnoea • Saturations 85% on air • Tachycardia 150bpm AF • Raised JVP and peripheral oedema • Widespread wheeze • Bilateral inspiratory crackes
What are the possible causes of SOB? • LVF • Decompensation from fast AF • COPD • Cor pulmonale
How can you distinguish cardiac and respiratory causes? • Echo – good biventricular function, LVEF 65%, normal valves, mild TR • ECG – no ischaemic changes • Spirometry – FEV1 1.62 (38% predicted), FVC 3.09, ratio FEV1/FVC 52% • ABG when not acutely SOB – pH 7.426, pO2 6.31, pCO2 7.19 SaO2 82% • CXR
Treatment at discharge • Combivent • Ramipril • Furosemide • Bisoprolol • Digoxin • Spironolactone
Treatment of cor pulmonale • LTOT assessment • Diuretics • No evidence for ACEI, calcium channel blockers, alpha blockers or digoxin unless AF,
Follow up • Definite symptomatic improvement when ramipril dose increased • Still SOB on short distances • Minor improvement in spirometry – still obstructive • Sats improved to 92% on air – not keen on ambulatory oxygen assessment
Case 3 • Age 46 female • Admitted with wheeze, productive cough, fever • Quite slow to recover – 4-5days as IP • Smoker • Operation for scoliosis aged 12 • Discharged on combivent and becotide • Seen in OPD in 6 weeks • Felt back to normal, but still SOBOE
What sort of defect do you think her spirometry showed? • Mixed defect • FEV1 1.10 (41% pred) • FVC 1.54 (49% pred) • FEV1/FVC 71% • After ventolin • FEV1 1.45l (132%) • PEFR from 170 to 240 • sats 97% on air
How would you distinguish asthma and COPD in this patient? • Spirometry alone cannot separate • clinical features • longitudinal variation • bronchodilator response (>400ml) • Steroid response (>400ml) • PEFR variability >20%
Spirometric reversibility testing • Not required routinely • May be inconsistent, not reproducible • Misleading unless change in FEV1 >400ml • Arbitrary definition of significant change • Response to long term therapy not predicted by acute reversibility testing
COPD vs asthma • Clinically significant COPD not present if FEV1 and FEV1/FVC ratio return to normal with drug therapy • Imaging and TLCO may help resolve difficult cases • TLCO (gas transfer) may be reduced in COPD and may be increased in asthma. • Clinical history as good as bronchial biopsies……
Opportunistic case finding • Knowledge of abnormal lung function as part of a motivational package significantly affects the success of smoking cessation therapy. • Cost effectiveness depends on prevalence of undetected COPD and smoking cessation success rate. • Over 35 current or ex smokers with a chronic cough.
Specialist referral - 1 • Diagnostic uncertainty • Suspected severe COPD • Patient requests second opinion • Onset of cor pulmonale • Assessment for oxygen therapy • Assessment for nebuliser • Assessment for long term oral steroids
Specialist referral - 2 • Bullous lung disease • Rapid decline in FEV1 • Assessment for pulmonary rehab • Assessment for thoracic surgery • Dysfunctional breathing • Aged under 40 • Frequent infections • Haemoptysis
Summary • Spirometry – pitfalls • Assessing severity • Main differentials – asthma and cardiac failure • Reasons for specialist referral