An attempt to analyze the relation between hospital surgical volume and clinical outcome

Abstract

The aim of this study was to investigate the relation between hospital volume and clinical surgical outcome for 10 cardiac, lung, and esophageal surgical procedures. The Committee for Scientific Affairs of the Japanese Association for Thoracic Surgery collected the pooled data on cardiac, lung, and esophageal surgical procedures between 2000 and 2004 from the annual reports. The relation between operative mortality (30-day or in-hospital mortality) and hospital volume was analyzed using a logistic regression model. The surgical procedures studied were surgery for acquired cardiac diseases [coronary artery bypass grafting (CABG), valve procedures, acute type A dissection surgery], total CABG (elective + emergency), elective CABG, emergency CABG, single-valve surgery, acute type A dissection surgery, open heart surgery for the newborn, open heart surgery for the infants, lung cancer surgery, and esophageal cancer surgery. The data used in this study were not risk-adjusted. The data on the relation between hospital volume and operative mortality generally tended to show an inverse correlation for all 10 cardiac, lung, and esophageal surgical procedures; that is, the higher was the volume the lower was the mortality. However, wide variations in operative mortality were noted among the very-low-volume hospital groups. An inverse correlation was noted between hospital volume and operative mortality in the present study, although wide variations in clinical outcome were noted among the very low-volume hospitals. Further analysis is warranted using risk-adjusted data.