Change in lung function early after endoscopic bronchial valve placement in patients with chronic cavitary tuberculosis

Abstract

The goal of this study was to analyze qualitative and quantitative changes in pulmonary ventilation and gas exchange early after endobronchial valve (EBV) placement intended to induce artificial local collapsed lung in patients with cavitary pulmonary tuberculosis. Methods. The study involved 74 patients with cavitary pulmonary tuberculosis underwent EBV placement to achieve cavity closure. As a result of EBV placement, one to two lung segments were blocked in 25 patients, three lung segments were blocked in 37 patients, and four to five lung segments were blocked in 12 patients. Pulmonary function and blood gases were measured in all patients before and 4 to 6 weeks after placing EVB. Results. Pulmonary ventilation and gas exchange parameters changed early after EBV placement in > 50% of patients. FVC and blood gas parameters changed more often than spirometry parameters. Functional improvement was considered in cases of blood gas improvement and, less frequently, in cases of VC improvement. Functional worsening was considered in cases in lung function decrease and development of mixed (coexisting obstructive and restrictive) abnormalities. Conclusion. In patients with cavitary pulmonary tuberculosis, EBV placement caused functional worsening more likely in patients with normal lung function at baseline. Functional worsening after EBV placement was 3- to 10-fold less likely in those with pulmonary ventilation abnormalities, such as VC decrease or bronchial obstruction, at baseline. Functional improvement after EBV placement was more often seen in moderately decreased lung functional parameters at baseline but not in patients with normal lung function.