Chronic obstructive pulmonary disease: Difference between revisions
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+ | ==Background== |
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+ | *Slowly progressive disease involving airways and lung parenchyma characterized by persistent airflow limitation |
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+ | ===Etiology=== |
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+ | *Tobacco smoke is by far the most common cause |
− | ** |
+ | **Usually >10 pack-year history |
− | * |
+ | *Biofuel smoke (wood, animal dung, coal, crop residues), organic or inorganic dust, chronic untreated asthma, air pollution |
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− | == Pathophysiology == |
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− | == Investigations == |
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− | == |
+ | ==Management== |
− | === |
+ | ===Acute=== |
− | * |
+ | *See [[Acute exacerbation of COPD]] |
− | === |
+ | ===Chronic=== |
− | * |
+ | *Preventative/non-pharmacologic |
− | ** |
+ | **Smoking cessation (improves survival), education |
− | ** |
+ | **Flu shots, pneumococcal vaccination |
− | ** |
+ | **Pulmonary rehabilitation (improves survival if within 4 weeks of exacerbation) |
− | * |
+ | *Step-wise puffers: note that no puffers improve survival |
− | ** |
+ | **Short-acting anticholinergic bronchodilators prn: [[ipratropium]]/[[salbutamol]] |
− | ** |
+ | **Long-acting anticholinergic bronchodilators: [[tiotropium]] (Spiriva) |
− | ** |
+ | **Long-acting beta-agonist: [[salmeterol]] or [[formoterol]] |
− | ** |
+ | **Inhaled corticosteroid (ICS): decreases frequency of exacerbations, but increases risk of pneumonia |
+ | **Combination puffers include [[fluticasone]]/[[salmeterol]] (Advair) |
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+ | *Home oxygen |
− | ** |
+ | **Improves survival if: |
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− | *** |
+ | ***Resting PaO2 < 55mmHg |
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− | ** |
+ | **Target SpO<sub>2</sub> >90% |
− | ** |
+ | **May not improve dyspnea |
− | * |
+ | *If frequent exacerbations, consider [[roflumilast]] or [[azithromycin]] or [[NAC]] |
− | * |
+ | *If daytime pCO<sub>2</sub> >52 mmHg, consider home non-invasive ventilation |
− | === |
+ | ===Surgical Interventions=== |
− | ==== |
+ | ====Lung Volume Reduction Surgery==== |
− | * |
+ | *Indicated if: |
− | ** |
+ | **Severe COPD |
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+ | **Symptomatic despite maximal pharmacologic therapy |
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+ | **Completed pulmonary rehabilitation |
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+ | **Evidence of bilateral predominant upper-lobe emphysema on CT |
− | ** |
+ | **Postbronchodilator total lung capacity greater than 100% and residual lung volume greater than 150% of predicted |
− | ** |
+ | **Maximum FEV1 greater than 20% and less than or equal to 45% of predicted and DLCO greater than or equal to 20% of predicted |
− | ** |
+ | **Ambient air arterial PCO2 less than or equal to 60 mm Hg (8.0 kPa) and arterial PO2 greater than or equal to 45 mm Hg (6.0 kPa) |
− | * |
+ | *Can decrease mortality in patients with heterogeneous, primarily upper-lobe emphysema |
− | ==== |
+ | ====Lung Transplantation==== |
− | * |
+ | *Indicated if: |
− | ** |
+ | **Pulmonary hypertension, cor pulmonale, or both despite oxygen therapy |
− | ** |
+ | **History of exacerbation associated with acute hypercapnia |
− | ** |
+ | **FEV1 less than 20% of predicted with DLCO less than 20% of predicted or homogeneous distribution of emphysema |
− | * |
+ | *Contraindications includes: active smoking or substance use, cancer within 2 years, organ dysfunction, incurable chronic infection, anatomical abnormalities, lack of social support, or untreated psychiatric disorder |
− | * |
+ | *Improves quality of life |
− | === |
+ | ===Symptomatic Management of Advanced COPD=== |
− | * |
+ | *Can use oral opioids for dyspnea |
− | * |
+ | *Walking aids and pursed-lip breathing |
− | * |
+ | *Home oxygen if hypoxemic at rest, but may not affect quality of life |
− | * |
+ | *Also: neuromuscular electrical muscule stimulation and chest wall vibration |
− | * |
+ | *No role for anxiolytics or antidepressants |
− | == |
+ | ==Further Reading== |
− | * |
+ | *CTS guidelines |
− | * |
+ | *TORCH trial: Jenkins CR, ''et al.'' [https://dx.doi.org/10.1186%2F1465-9921-10-59 Efficacy of salmeterol/fluticasone propionate by GOLD stage of chronic obstructive pulmonary disease: analysis from the randomised, placebo-controlled TORCH study]. ''Respir Res''. 2009;10(1):59. |
− | ** |
+ | **LABA+ICS decreased exacerbations and hospitalizations compared to either alone, but ICS increased pneumonia |
[[Category:Respirology]] |
[[Category:Respirology]] |
Latest revision as of 11:51, 21 October 2021
Background
- Slowly progressive disease involving airways and lung parenchyma characterized by persistent airflow limitation
Etiology
- Tobacco smoke is by far the most common cause
- Usually >10 pack-year history
- Biofuel smoke (wood, animal dung, coal, crop residues), organic or inorganic dust, chronic untreated asthma, air pollution
Risk Factors
- Smoking
- Age
- Biofuel use
GOLD Classification
- Class I (mild): FEV1 ≥80%
- Class II (moderate): FEV1 50-79%
- Class III (severe): FEV1 30-49%
- Class IV (very severe): FEV1 ≤29%
Clinical Manifestations
- Dyspnea, chronic cough or sputum production
- Match test (cannot blow out a lit match)
Differential Diagnosis
- Dyspnea
- Pulmonary disease
- Airways: asthma, bronchiectasis
- Parenchyma: ILDs
- Vessels: PH, PE
- Chronic cough
Diagnosis
- Pulmonary function tests (PFTs)
- Post-bronchodilator FEV1/FVC ratio <0.7 for diagnosis
- Possibly elevated TLC (gas trapping) and low DLCO (suggests emphysema)
Management
Acute
Chronic
- Preventative/non-pharmacologic
- Smoking cessation (improves survival), education
- Flu shots, pneumococcal vaccination
- Pulmonary rehabilitation (improves survival if within 4 weeks of exacerbation)
- Step-wise puffers: note that no puffers improve survival
- Short-acting anticholinergic bronchodilators prn: ipratropium/salbutamol
- Long-acting anticholinergic bronchodilators: tiotropium (Spiriva)
- Long-acting beta-agonist: salmeterol or formoterol
- Inhaled corticosteroid (ICS): decreases frequency of exacerbations, but increases risk of pneumonia
- Combination puffers include fluticasone/salmeterol (Advair)
- Home oxygen
- Improves survival if:
- Resting PaO2 < 55mmHg
- Resting PaO2 < 60mmHg plus cor pulmonale
- Target SpO2 >90%
- May not improve dyspnea
- Improves survival if:
- If frequent exacerbations, consider roflumilast or azithromycin or NAC
- If daytime pCO2 >52 mmHg, consider home non-invasive ventilation
Surgical Interventions
Lung Volume Reduction Surgery
- Indicated if:
- Severe COPD
- Symptomatic despite maximal pharmacologic therapy
- Completed pulmonary rehabilitation
- Evidence of bilateral predominant upper-lobe emphysema on CT
- Postbronchodilator total lung capacity greater than 100% and residual lung volume greater than 150% of predicted
- Maximum FEV1 greater than 20% and less than or equal to 45% of predicted and DLCO greater than or equal to 20% of predicted
- Ambient air arterial PCO2 less than or equal to 60 mm Hg (8.0 kPa) and arterial PO2 greater than or equal to 45 mm Hg (6.0 kPa)
- Can decrease mortality in patients with heterogeneous, primarily upper-lobe emphysema
Lung Transplantation
- Indicated if:
- Pulmonary hypertension, cor pulmonale, or both despite oxygen therapy
- History of exacerbation associated with acute hypercapnia
- FEV1 less than 20% of predicted with DLCO less than 20% of predicted or homogeneous distribution of emphysema
- Contraindications includes: active smoking or substance use, cancer within 2 years, organ dysfunction, incurable chronic infection, anatomical abnormalities, lack of social support, or untreated psychiatric disorder
- Improves quality of life
Symptomatic Management of Advanced COPD
- Can use oral opioids for dyspnea
- Walking aids and pursed-lip breathing
- Home oxygen if hypoxemic at rest, but may not affect quality of life
- Also: neuromuscular electrical muscule stimulation and chest wall vibration
- No role for anxiolytics or antidepressants
Further Reading
- CTS guidelines
- TORCH trial: Jenkins CR, et al. Efficacy of salmeterol/fluticasone propionate by GOLD stage of chronic obstructive pulmonary disease: analysis from the randomised, placebo-controlled TORCH study. Respir Res. 2009;10(1):59.
- LABA+ICS decreased exacerbations and hospitalizations compared to either alone, but ICS increased pneumonia