Hospital Volume and Outcomes of Robot-Assisted Lobectomies

BACKGROUND: The positive impact of hospital operative volume on outcomes following video-assisted thoracoscopic surgery has been established. The goal of this study was to determine whether or not this volume/outcome relationship translates to robot-assisted thoracoscopic surgery (RobATS) lobectomy. METHODS: Patients who underwent RobATS lobectomy were identified between 2008 and 2013 in the Healthcare Cost and Utilization Project National Inpatient Sample database. Hospital volume, as well as demographic, clinical, and health-care system-related factors were selected as potential predictors of outcomes. Outcome variables included length of stay (LOS), inpatient mortality, and complications. Hospitals were designated by quartiles according to annual case volume, with very low-volume defined as the first quartile and highvolume defined as the fourth quartile. Regression analyses were used to identify independent predictors of the outcomes of interest. RESULTS: A total of 8,253 RobATS lobectomies were identified. Compared with very low-volume centers, patients at high-volume hospitals had a shorter mean LOS (5.8 vs 6.5 days; P = .001) and decreased mortality rate (0.5% vs 1.9%; P < .001) but more complications (28.1% vs 27.6%; P = .025). In multivariable analysis, high hospital volume was prognostic for decreased mortality (OR, 0.134; P < .001) and shorter LOS (0.2 days; SE, 0.05; P <. 001). Hospital volume was not prognostic for any complications, including pulmonary, cardiovascular, intraoperative, or infectious complications. CONCLUSIONS: Undergoing lobectomy at high-volume RobATS centers confers favorable mortality and LOS outcomes compared with very low-volume centers. In this relatively early phase of adoption of RobATS, the long-term clinical impact of differences in LOS as well as the lack of clinical impact on the incidence of complications remain to be determined more definitively. However, the beneficial effect of volume on mortality suggests a need for the careful adoption of this promising technology.