Case Presentation
A 65-year-old man with severe chronic obstructive disease (COPD; forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC], 27; FEV1 25% of predicted; residual volume 170% of predicted for his age and height) was seen in the pulmonary clinic. His medications include a long-acting beta agonist (LABA)/long-acting muscarinic antagonist (LAMA) combination that he uses twice daily as advised. He uses his rescue albuterol inhaler roughly once a week. The patient complains of severe disabling shortness of breath with exertion and severe limitation of his quality of life because of his inability to lead a normal active life. He is on 2 L/min of oxygen at all times. He has received pulmonary rehabilitation in hopes of improving his quality of life but can only climb a flight of stairs before he must stop to rest. He asks about options but does not want to consider lung transplantation today. His most recent chest computed tomography (CT) scan demonstrates upper lobe predominant emphysematous changes with no masses or nodules.
What are the patient's options at this time?
Lung volume reduction surgery (LVRS) attempts to reduce space-occupying severely diseased, hyperexpanded lung, thus allowing the relatively normal adjoining lung parenchyma to expand into the vacated space and function effectively.1 Hence, such therapies are suitable for patients with emphysematous lungs and not those with bronchitic-predominant COPD. LVRS offers a greater chance of improvement in exercise capacity, lung function, quality of life, and dyspnea in the correctly chosen patient population, as compared with pharmacologic management alone.2 However, the procedure is associated with risks, including higher short-term morbidity and mortality.2 Patients with predominantly upper-lobe emphysema and a low maximal workload after rehabilitation were noted to have lower mortality, a greater probability of improvement in exercise capacity, and a greater probability of improvement in symptoms if they underwent surgery compared to medical therapy alone.2 On the contrary, patients with predominantly non–upper-lobe emphysema and a high maximal workload after rehabilitation had higher mortality if they underwent surgery compared to receiving medical therapy alone.2 Thus, a subgroup of patients with homogeneous emphysema symmetrically affecting the upper and lower lobes are considered to be unlikely to benefit from this surgery.2,3
Valves and other methods of lung volume reduction such as coils, sealants, intrapulmonary vents, and thermal vapor in the bronchi or subsegmental airways have emerged as new techniques for nonsurgical lung volume reduction.4-9 Endobronchial-valve therapy is associated with improvement in lung function and with clinical benefits that are greatest in the presence of heterogeneous lung involvement. This works by the same principle as LVRS, by reduction of the most severely diseased lung units, expansion of the more viable, less emphysematous lung results in substantial improvements in lung mechanics.10,11 The most important complications of this procedure include pneumonia, pneumothorax, hemoptysis, and increased frequency of COPD exacerbation in the following 30 days. The fact that a high-heterogeneity subgroup had greater improvements in both the FEV1 and distance on the 6-minute walk test than did patients with lower heterogeneity supports the use of quantitative high-resolution computed tomography (HRCT) in selecting patients for endobronchial-valve therapy.12 The HRCT scans also help in identifying those with complete fissures, a marker of lack of collateral ventilation (CV+) between different lobes. Presence of CV+ state predicts failure of endobronchial valve and all forms of endoscopic LVRS.13 Bronchoscopic thermal vapor ablation (BTVA) therapy can potentially work on a subsegmental level and be successful for treatment of emphysema with lack of intact fissures on CT scans. Other methods that have the potential to be effective in those with collateral ventilation would be endoscopic coil therapy and polymeric lung volume reduction.11,14 Unfortunately, there are no randomized controlled trial data demonstrating clinically meaningful improvement following coil therapy or polymeric lung volume reduction in this CV+ patient population. Vapor therapy is perhaps the only technique that has been found to be effective in upper lobe predominant emphysema even with CV+ status.13
Our patient has evidence of air trapping and emphysema based on a high residual volume. A CT scan of the chest can determine the nature of the emphysema (heterogeneous versus homogenous) and based on these findings, further determination of the best strategy for lung volume reduction can be made.
Is there a role for long-term oxygen therapy?
Long-term oxygen therapy (LTOT) used for more than 15 hours a day is thought to reduce mortality among patients with COPD and severe resting hypoxemia.15-18 More recent studies have failed to show similar beneficial effects of LTOT. A recent study examined the effects of LTOT in randomized fashion and determined that supplemental oxygen for patients with stable COPD and resting or exercise-induced moderate desaturation did not affect the time to death or first hospitalization, time to first COPD exacerbation, time to first hospitalization for a COPD exacerbation, the rate of all hospitalizations, the rate of all COPD exacerbations, or changes in measures of quality of life, depression, anxiety, or functional status.19
Our patient is currently on long-term oxygen therapy and in spite of some uncertainty as to its benefit, it is prudent to order oxygen therapy until further clarification is available.
What is the role of pulmonary rehabilitation?
Pulmonary rehabilitation is an established treatment for patients with chronic lung disease.20 Benefits include improvement in exercise tolerance, symptoms, and quality of life, with a reduction in the use of health care resources.21 A Spanish population-based cohort study that looked at the influence of regular physical activity on COPD showed that patients who reported low, moderate, or high physical activity had a lower risk of COPD admissions and all-cause mortality than patients with very low physical activity after adjusting for all confounders.22