Impact of physical functions on short-term outcomes after thoracoscopic lobectomy for early-stage non-small cell lung cancer

Abstract

Background:Many studies have demonstrated that thoracoscopic lobectomy is superior to open thoracotomy in terms of short-termoutcomes in patientswith early-stage non-small cell lung cancer. However, few studies have analyzed the predictor of the postoperative deteriorationof performance status or complication in patients undergoing thoracoscopic lobectomy, despite considerable research in open thoracotomy. Besides, those studies did not cover the physical functions such as a muscle strength or an exercise capacity. Purpose: The purposes of this study were to identify predictors of short-term outcomes including the postoperative deterioration of the performance status and cardiopulmonary complications and to determine whether preoperative physical function including the lower-limb muscle strength and exercise capacity is associated with the short-term outcomes. Methods: Between June 2005 and October 2012, we retrospectively reviewed 188 consecutive patients who underwent thoracoscopic lobectomy and the perioperative pulmonary rehabilitation for preoperative stage I non-small cell lung cancer. Demographic, lung and physical functions, surgical, and oncologic data were initially analyzed by using univariate analysis. Those with a P value of less than 0.2 of univariate analyses were used as independent variables in themultivariate logistic regression analyses. Pulmonary rehabilitation that consisted of postoperative early mobilization and progressive exercise training was administered during the patients’ hospitalization. Results: The incidences of postoperative deterioration of performance status and cardiopulmonary complication were 13.8% (n= 26) and 19.1% (n= 36), respectively. Multivariate analyses showed that percent of predicted diffusion capacity of the lung for carbon monoxide (<80.0%), quadriceps muscle strength (<40% of body weight), and pathologic stage (≥stage IIA) were independent risk factors for the deterioration of performance status after surgery (odds ratio, 3.44; P= 0.0146, odds ratio, 4.53; P= 0.007, odds ratio, 9.5; P< 0.001, respectively), and comorbidity of chronic obstructive pulmonary disease, six-minute walk distance (<400m), and pathologic stage (≥stage IIA) were independent risk factors for the postoperative cardiopulmonary complication (odds ratio, 5.88; P< 0.001, odds ratio, 4.04; P= 0.031, odds ratio, 4.81; P= 0.002, respectively). Conclusion(s): Not only greater pathologic stage, diffusion capacity of the lung, and chronic obstructive pulmonary disease, which were similar to those reported in previous studies, but also poor physical function was associated with worse short-term outcomes. Therefore, the evaluation of preoperative physical function may be useful as a predictor of short-term outcomes. Implications: This study suggest that the evaluation of preoperative physical function may be helpful for a risk stratification for the deterioration of performance status and the development of cardiopulmonary complication after surgery. These findings could be incorporated into a physical therapy practice in patient with lung cancer being considered for resectional surgery even by using a minimally invasive surgical approach. Further studies are warranted to determine whether a perioperative physical therapy with the aim of increasingmuscle strength and exercise capacity can improve the short-term outcomes.