Pulmonary function changes after uniportal video-assisted thoracoscopic anatomical lung resection

Objective: The superiority of segmentectomy over lobectomy with regard to preservation of pulmonary function is controversial. This study aimed to examine changes in pulmonary function after uniportal video-assisted thoracoscopic surgery (VATS) according to the number of resected segments. Methods: We retrospectively reviewed 135 consecutive patients who underwent anatomical lung resection via uniportal VATS from April 2015 to December 2020. Pulmonary function loss was evaluated using forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). Patients were grouped according to number of resected segments: one-segment (n = 33), two segments (n = 22), three segments (n = 40), four segments (n = 15), and five segments (n = 25). Results: Clinical characteristics did not significantly differ between groups, except for tumor size. Mean follow-up was 8.96 ± 3.16 months. FVC loss was significantly greater in five-segment resection (10.8%) than one-segment (0.97%, p = 0.008) and two-segment resections (2.44%, p = 0.040). FEV1 loss was significantly greater in five-segment resection (15.02%) than one-segment (3.83%, p < 0.001), two-segment (4.63%, p = 0.001), and three-segment resections (7.63%, p = 0.007). Mean FVC loss and FEV1 loss increased linearly from one-segment resection to five-segment resection. Mean loss in FVC and FEV1 per segment resected was 2.16% and 3.00%, respectively. Conclusions: Anatomical lung resection of fewer segments was associated with better preservation of pulmonary function in patients undergoing uniportal VATS, and function loss was approximately 2%–3% per segment resected with linear relationship.