TOC | Pulm

Chronic Obstructive Diseases of the Lung  (COPD)                                       REF:  Best Dx/ Best Rx 2006 Gerald W. Staton, Jr., M.D.

Definition/Key Clinical Features  |  Differential Diagnosis  | Best Tests  | Best Therapy  | Best References

Definition/Key Clinical Features Partially reversible airflow obstruction caused by chronic bronchitis and/or emphysema Predominant Chronic Bronchitis ("Blue Bloater") History of cigarette smoking Chronic productive cough Frequent chest infections Wheezing Orthopnea Signs of right heart failure Predominant Emphysema ("Pink Puffer") Dyspnea Weight loss Hyperinflated lung fields

Differential Diagnosis Bronchiolitis obliterans Asthma Emphysema caused by ±1-antitrypsin deficiency Bullous lung disease Bronchiectasis Cystic fibrosis Primary ciliary dyskinesia

Best Tests Pulmonary Function Tests Should be performed in all smokers with any respiratory symptoms and all smokers > 45 yr Spirometry shows reduction in FEV1/FVC and FEV1 Total lung capacity normal or increased Arterial blood gases Chronic bronchitis: markedly reduced Pao2; increased Paco2; normal diffusing capacity of lung for CO (DLCO) Emphysema: mildly reduced Pao2; normal or decreased Paco2; decreased DLCO Chest X-ray Chronic bronchitis: normal or increased bronchovascular markings at the lung bases Emphysema: arterial deficiency in lung periphery; hyperinflation; bullous disease Computed Tomography CT of the chest can show upper lobe emphysema in patients without abnormalities in pulmonary function

Nonpharmacologic Therapy Smoking cessation For chronic hypoxia, supplemental oxygen, 15–24 hr/day, sufficient to maintain > 90% arterial oxygen saturation For patients with Pao2 d 55 mm Hg For patients with Pao2 d 59 mm Hg and peripheral edema, hematocrit 55%, or P pulmonale on ECG Influenza and pneumococcal vaccine Physical training increases exercise capacity even in patients with advanced disease Respiratory muscle training with an inspiratory resistor can improve endurance Intermittent application of negative pressure or noninvasive positive pressure ventilation at night can improve daytime symptoms

Pharmacologic Therapy   Bronchodilators: can produce 10% increase in maximal expiratory airflow Inhaled long-acting anticholinergics: first-line therapy Tiotropium/Spiriva , DPI (dry-powder inhaler), 18 µg/capsule Maintenance dose: 1 capsule q. day; Cost/mo: $115 Exacerbation dose: not recommended Inhaled short-acting anticholinergics Ipratropium bromide/Atrovent Nebulizer, 0.25 mg/ml; may mix with albuterol in same nebulizer Maintenance dose: 0.5 mg q. 6 hr Exacerbation dose: 0.5 mg q. 2–8 hr MDI (metered-dose inhaler), 18 µg/puff: as effective as nebulizer when used with spacer Maintenance dose: 2–6 puffs q. 6 hr;  Cost/mo: $215 Exacerbation dose: 3–8 puffs q. 3–4 h;  Cost/mo: $392 Inhaled long-acting beta2 agonists (should be used for maintenance therapy) Salmeterol/Serevent: slower onset of action than short-acting beta2 agonists MDI, 21 µg/puff Maintenance dose: 2 puffs q. 12 hr Exacerbation dose: not recommended DPI, 50 µg/blister Maintenance dose: 1 blister q. 12 hr;  Cost/mo: $80 Exacerbation dose: not recommended Formoterol/Foradil: faster onset of action than salmeterol DPI, 12 µg/capsule Maintenance dose: 1 capsule q. 12 hr; Cost/mo: $80 Exacerbation dose: not recommended Inhaled short-acting beta2 agonists: second-line therapy Albuterol/Ventolin/Proventil   Nebulizer, 5 mg/ml: dilute aerosols to minimum of 4 ml at gas flow of 6–8 L/min Maintenance dose: 1.25–5.0 mg q. 4–8 hr p.r.n. Exacerbation dose: 5.0 mg q. 2 hr MDI, 84 µg/puff: as effective as nebulizer when used with spacer Maintenance dose: 2–4 puffs q. 6 hr p.r.n.; Cost/mo: $34 Exacerbation dose: 3–8 puffs q. 2 hr ; Cost/mo: $202 DPI, 200 µg/capsule Maintenance dose: 1–2 capsules q. 6 hr p.r.n. Exacerbation dose: not studied in exacerbations Bitolterol/Tornalate Nebulizer, 2 mg/ml Maintenance dose: 0.5–3.5 q. 4–8 hr p.r.n. Exacerbation dose: not studied in exacerbations MDI, 370 µg/puff Maintenance dose: 2–4 puffs q. 6 hr p.r.n. Exacerbation dose: not studied in exacerbations Pirbuterol/Maxair: MDI, 200 µg/puff Maintenance dose: 2–4 puffs q. 6 hr p.r.n. ; Cost/mo: $96 Exacerbation dose: not studied in exacerbations Combined short-acting beta2 agonist and anticholinergic (when both are indicated) Albuterol + ipratropium bromide/Atrovent, MDI: albuterol, 90 µg/puff; ipratropium bromide, 18 µg/puff Maintenance dose: 2–4 puffs q. 6 hr p.r.n.; Cost/mo: $140 Exacerbation dose: 3–8 puffs q. 2 hr; Cost/mo: $801 Oral Corticosteroids             Should be avoided except for acute exacerbations Should be given in the lowest possible dose, preferably on alternate days Complications of prolonged therapy: weight gain, osteoporosis, hypertension, diabetes, cataracts, myopathy Inhaled Corticosteroids For patients who have recurrent attacks of wheezing For patients who have significant acute response to inhaled bronchodilators (> 20% increase in FEV1) For patients who have sputum eosinophilia Medium to high doses may be more effective than lower doses May carry a small risk for cataracts Inhaled Corticosteroids for COPD          Beclomethasone/QVAR: third-highest potency Low dosage: 168–504 µg (42 µg/puff: 4–12 puffs/day; 84 µg/puff: 2–6 puffs/day)   Cost/mo: 42 µg/puff: $146 Medium dosage: 504–840 µg (42 µg/puff: 12–20 puffs/day; 84 µg/puff: 6–10 puffs/day)   Cost/mo: 42 µg/puff: $240 High dosage: > 840 µg (42 µg/puff: > 20 puffs/day; 84 µg/puff: > 10 puffs/day)   Cost/mo: 42 µg/puff: > $240 Budesonide/Pulmicort: second-highest potency Low dosage: 200–400 µg (200 µg/puff: 1–2 inhalations/day)   Cost/mo: $41 Medium dosage: 400– 600 µg (200 µg/puff: 2– 3 inhalations/day)   Cost/mo: $55 High dosage: > 600 µg (200 µg/puff: > 3 inhalations/day)   Cost/mo: > $55 Flunisolide/Aerobid: lowest potency Low dosage: 500–1,000 µg (250 µg/puff: 2–4 puffs/day)   Cost/mo: $22 Medium dosage: 1,000–2,000 µg (250 µg/puff: 4–8 puffs/day)   Cost/mo: $46 High dosage: > 2,000 µg (250 µg/puff: > 8 puffs/day)   Cost/mo: > $46 Fluticasone/Flovent: highest potency Low dosage: 88–264 µg (44 µg/puff: 2–6 puffs/day; 110 µg/puff: 1–2 puffs/day; 220 µg/puff: 1 puff/day)   Cost/mo: 44 µg/puff: $85; 110 µg/puff: $38; 220 µg/puff: $29 Medium dosage: 264–660 µg (44 µg/puff: 6–15 puffs/day; 110 µg/puff: 2–6 puffs/day; 220 µg/puff: 1–2 puffs/day) Cost/mo: 44 µg/puff: $227; 110 µg/puff: $108; 220 µg/puff: $58 High dosage: > 660 µg (44 µg/puff: > 15 puffs/day; 110 µg/puff: > 6 puffs/day; 220 µg/puff: > 3 puffs/day) Cost/mo: 44 µg/puff: > $227; 110 µg/puff: > $108; 220 µg/puff: > $87 Triamcinolone/Azmacort: lowest potency Low dosage: 400–1,000 µg (100 µg/puff: 4–10 puffs/day)   Cost/mo: $152 Medium dosage: 1,000–2,000 µg (100 µg/puff: 10–20 puffs/day)   Cost/mo: $213 High dosage: > 2,000 µg (100 µg/puff: > 20 puffs/day)   Cost/mo: > $213 Diuretics/Vasodilators For patients with far advanced airflow obstruction who have cor pulmonale and right heart failure Diuretics can be used for symptomatic relief of peripheral edema, with care to avoid chloride depletion from long-term use of diuretics Arterial vasodilators, including hydralazine and nifedipine, can reduce pulmonary arterial hypertension but may not produce sustained symptomatic improvement or prolonged survival There is risk of systemic hypotension and renal hypoperfusion Long-term supplemental oxygen is more effective than drugs to reduce pulmonary arterial resistance

Surgical Therapy Lung volume reduction surgery Can improve exercise capacity in some patients Can improve survival in patients with upper lobe emphysema and low exercise capacity after rehabilitation Lung transplantation An option for younger patients with advanced chronic airflow obstruction (single-lung transplantation for patients with emphysema, bilateral for those with chronic bronchitis) Five-year survival after lung transplantation is 57%

Best References Calverley PM, et al: Lancet 362:1053, 2003 Calverley PM: Eur Respir J 47(suppl):26s, 2003 Celli BR, et al: Eur Respir J 23:932, 2004 Fabbri LM, et al: Eur Respir J 22:1, 2003 Stoller JK: N Engl J Med 346:988, 2002

          2006