The Effect of Lung Volume Reduction Surgery on Chronic Obstructive Pulmonary Disease Exacerbations

Abstract

Rationale: Lung volume reduction surgery (LVRS) has been demonstrated to provide a functional and mortality benefit to a select group of subjects with chronic obstructive pulmonary disease (COPD). The effect of LVRS on COPD exacerbations has not been as extensively studied, and whether improvement in postoperative lung function alters the risk of disease exacerbations is not known. Objectives: To examine the effect, and mechanism of potential benefit, of LVRS on COPD exacerbations by comparing the medical and surgical cohorts of the National Emphysema Treatment Trial (NETT). Methods: A COPD exacerbation was defined using Centers for Medicare and Medicaid Services data and International Classification of Diseases, Ninth Revision, discharge diagnosis. Measurements and Main Results: There was no difference in exacerbation rate or time to first exacerbation between the medical and surgical cohorts during the year before study randomization (P 5 0.58 and 0.85, respectively). Postrandomization, the surgical cohort experienced an approximate 30% reduction in exacerbation frequency (P 5 0.0005). This effect was greatest in those subjects with the largest postoperative improvement in FEV 1 (P 5 0.04) when controlling for changes in other spirometric measures of lung function, lung capacities, and room air arterial blood gas tensions. Finally, LVRS increased the time to first exacerbation in both those subjects with and those without a prior history of exacerbations (P 5 0.0002 and P , 0.0001, respectively). Conclusions: LVRS reduces the frequency of COPD exacerbations and increases the time to first exacerbation. One explanation for this benefit may be the postoperative improvement in lung function. Clinical trial registered with www.clinicaltrials.gov (NCT 00000606). Keywords: COPD; LVRS; exacerbationChronic obstructive pulmonary disease (COPD) is responsible for an estimated 176 million hospital bed days per year in the United States and an annual loss of almost 60 million workdays (1). A significant portion of the health care costs incurred by COPD is due to acute exacerbations. Although the mainstays of medical treatment and prevention include inhaled long-acting bronchodilators and corticosteroids, their efficacy in this regard is debated (2-4). The basis for their presumed beneficial effect is a combination of their bronchodilating and antiinflammatory properties, effects that may offset the increased risk of exacerbations found with declining lung function (5-12). Given this, mechanical interventions that improve function, such as lung volume reduction surgery (LVRS), may reduce the frequency of acute exacerbations.Results from the National Emphysema Treatment Trial (NETT) suggest that there is a subset of subjects with COPD who obtain functional, quality-of-life, and mortality benefits from LVRS (13). Although still statistically significant at 3 years postrandomization, these postsurgical improvements in lung function for LVRS patients had attenuated and were approaching measurements made in the medical cohort. ...

Nonpharmacological treatment and relief of symptoms in COPD

“…LVRS reduces the frequency of COPD exacerbations and increases the time to first exacerbation. One explanation for this benefit may be the post-operative improvement in lung function [67].…”

The Impact of Emphysema on Chronic Obstructive Pulmonary Diseases

“…Although no studies or pharmacological trials have been designed to specifically evaluate this fact, it has been observed that patients with IC/TLC ratio < 0.25 o RV/TLC ratio > 50% have more exacerbations 44,46 . In the NETT study, it was observed that LVRS reduces the frequency of COPD exacerbations and increases the time to first exacerbation 47 . However, this effect was greatest in those subjects with the largest postoperative improvement in FEV 1, but changes in lung volumes estimated by a slow vital capacity (VC) and FRC were excluded from the multivariable Cox regression model (to determine whether changes in physiologic variables were associated with exacerbations).…”

“…However, this effect was greatest in those subjects with the largest postoperative improvement in FEV 1, but changes in lung volumes estimated by a slow vital capacity (VC) and FRC were excluded from the multivariable Cox regression model (to determine whether changes in physiologic variables were associated with exacerbations). The discrepancy could be related with the fact that the NETT study was not designed to evaluate exacerbations and this post-hoc analysis only included those exacerbations that required emergency room assistance or hospitalization 47 .…”

Prevention of Acute Exacerbations of Chronic Obstructive Pulmonary Disease

“…Имеются указания на возможные прямые и не прямые противовоспалительные эффекты ДДБД, связанные с их влиянием на провоспалительные клетки и медиаторы воспаления [19], однако данный вопрос нуждается в дальнейшем исследовании. При мечательно, что достоверное снижение числа обо стрений ХОБЛ (на 30 %) наблюдается и после хирур гической редукции объема легких [72], т. е. при вмешательствах, в принципе не обладающих пря мым противовоспалительным действием (бронходи лататоры, хирургическая редукция объема легких), может снижаться число обострений только за счет положительных изменений механики дыхания.…”