Effect of institutional case volume on mid-term mortality after coronary artery bypass grafting surgery.

OBJECTIVE: The impact of center case volume on mid-term postoperative outcome after coronary artery bypass grafting surgery (CABG) is still controversial and requires investigation. The aim of this study was to compare mid-term survival after CABG according to the institutional annual CABG case volume. METHODS: Adult patients (≥ 18 years) who underwent CABG from 2009 to 2016 were identified by searching National Health Insurance database of Korea for CABG procedure codes. Hospitals were classified into three groups based on annual case volume; low-volume centers (< 20 cases/year), medium-volume centers (20-50 cases/year), and high-volume centers (> 50 cases/year). RESULTS: A total of 22,575 CABG were performed in 95 centers during the study period, and 14,697 (65.1%) cases performed at 15 high-volume centers, 5,262 (23.3%) cases at 26 medium-volume centers, and 2,616 (11.6%) cases at 54 low-volume centers. The overall 1-year mortality rate was the lowest in high-volume centers (6.5%), followed by medium-volume centers (10.6%) and low-volume centers (15.2%). Logistic regression identified medium-volume centers (adjusted OR 1.30 [95% CI 1.15-1.49], P < 0.01) and low-volume centers (adjusted OR 1.75 [95% CI 1.51-2.03], P < 0.01) as risk factors for 1-year mortality after CABG compared to high-volume centers. In the Cox proportional hazard model, low- and medium-volume centers were significantly risk factors for poor survival (adjusted HR 1.41 [95% CI 1.31-1.54], P < 0.01 and HR 1.26 [95% CI 1.17-1.35], P < 0.01 for low- and medium-volume centers, respectively). CONCLUSIONS: Higher institutional case volume of CABG was associated with lower mid-term mortality.

Adjuvant chemotherapy as a risk factor for chronic postoperative pain after video-assisted thoracoscopic surgery: a 10-year single-centre retrospective study.

OBJECTIVES: The association between adjuvant chemotherapy (AC) and chronic postoperative pain (CPP) after video-assisted thoracoscopic surgery (VATS) for lung cancer resection has not yet been reported. We, therefore, investigated the association between AC and the long-term incidence of CPP after VATS. METHODS: We retrospectively reviewed 3015 consecutive patients who underwent VATS for lung cancer between 2007 and 2016. The patients were divided into 2 groups: those who received (AC group) and those who did not receive (non-AC group) AC within 3 months after VATS. Propensity score analysis was performed to adjust for baseline differences between the 2 groups. The cumulative incidence of CPP at the intervals of 3 months, over 36 months, was compared before and after matching. A Cox proportional hazards regression analysis was used to investigate the predictors of CPP after VATS. RESULTS: We included and assessed 2222 patients in this study. Of these, 320 patients (14.4%) received AC within 3 months post-VATS. The cumulative incidence of CPP during 36 months post-surgery was significantly higher in the AC group than in the non-AC group, before and after matching (log-rank test; P = 0.002 and 0.027, respectively). Cox proportional hazards regression analysis also showed that AC was a significant risk factor for CPP (hazard ratio 1.62, 95% confidence interval 1.16-2.28; P = 0.005). CONCLUSIONS: Our results indicate that AC is an important risk factor for CPP after VATS. Further understanding of the risk factors for CPP may facilitate its prediction and treatment.