Background: Recently published papers have shown that lobectomy improves lung function in selected patients with chronic obstructive pulmonary disease (COPD) months after surgery, but little information can be found discussing the effect of lobectomy on pulmonary function in the immediate period after surgery in these cases. The aim of this multicenter prospective study is to evaluate whether preoperative COPD influences the decrease of forced expiratory volume in 1 second the day after surgery.
Methods: One hundred eighty-five patients undergoing nonextensive lobectomy were included. Selection criteria and perioperative management were homogeneous; all procedures were performed by muscle-sparing or video-assisted thoracoscopic surgical approach. Multivariate regression analysis was performed to identify whether COPD index (calculated by adding the percent preoperative forced expiratory volume in 1 second to the preoperative ratio of forced expiratory volume in 1 second to forced vital capacity, both values taken in decimal form) had an independent and reliable association with the decrease in forced expiratory volume in 1 second observed on the first postoperative day corrected for the effect of other preoperative and operative factors. The regression analysis was then validated by bootstrap analysis.
Results: Thirty-day mortality of the series was 1.1% (2 patients) and cardio-respiratory morbidity 20% (37 patients). Patients with lower preoperative pulmonary volumes had lower postoperative decrease of the pulmonary function (Pearson correlation coefficient, 0.28; p < 0.001). At linear regression, COPD index (p = 0.008), modality of analgesia (p < 0.0001), pain score (p = 0.01), the percentage of functioning parenchyma removed during operation (p = 0.006), and the presence of coronary artery disease (p = 0.03) had independent and reliable influence on the dependent variable (p < 0.001 and 0.003, respectively).
Conclusions: Preoperative COPD degree (measured as COPD index) has a direct independent correlation with the decrease in postoperative forced expiratory volume in 1 second the day after surgery.