Postoperative pulmonary function changes according to the resected lobe: A 1-year follow-up study of lobectomized patients

Abstract

Background: Pulmonary function and patient complaints appear to improve up to 12 months after lobectomy but long-term prospective studies based on clinical data are scarce. Improvement in pulmonary function may depend on the area and extent of the resection and the time from the operation. This prospective study aimed to determine pulmonary function changes according to the resected lobe. Methods: This prospective study included 59 patients requiring single lobectomy. Total volume and low-attenuation volume (LAV) for each lobe and the entire lungs were calculated based on helical computed tomography images. Vital capacity (VC), forced expiratory volume in one second (FEV1), percent FEV1 (%FEV1), percent lung diffusion capacity for carbon monoxide (%DLco), %DLco divided by the alveolar volume (%DLco/VA), modified Medical Research Council (mMRC) grades, and COPD Assessment Test (CAT) scores were compared at 3, 6, and 12 months after surgery. Results: VC was higher at 12 months than at 3 months after right upper lobectomy (RUL) or right lower lobectomy (RLL). FEV1 and %FEV1 were higher at 12 months than at 6 months after left lower lobectomy (LLL). %DLco was higher at 12 months than at 3 months after RUL or left upper lobectomy (LUL). DLco/VA, mMRC grades, and CAT scores did not change significantly in the period from 3 to 12 months after any lobectomy procedure. Compared to the predicted postoperative values, the observed values of VC for RUL, RLL, and LUL; FEV1 for RLL; %FEV1 for RLL and LUL; %DLco for LUL; and %DLco/VA for all lobectomy procedures were higher at 12 months. Conclusions: Improvements in pulmonary function and symptoms varied according to the resected lobe. Some of the observed pulmonary function values were higher than the predicted postoperative values. Pulmonary function changes may be related to the location, volume, and extent of emphysematous changes.