Association of allogeneic red-blood cell transfusion with surgeon case-volume

Background: Surgeon case-volume predicts a variety of patient outcomes. We hypothesize that surgeon case-volume predicts RBC transfusion across different surgical procedures. Methods: We performed a cohort study of 372,670 in-patient surgical cases in the 52 non-federal hospitals in Maryland between 2004 and 2005. The main outcome measure was relative risk of receiving a transfusion. Results: Overall, 13.9% of patients received a transfusion. Patients seen by the highest case-volume surgeons (>161 cases/y) were more likely to receive a transfusion (16% versus 11%, P < 0.01) compared with middle case-volume surgeons (89-161 cases/y). After adjusting for confounders, the highest case-volume patients were still at increased risk of transfusion [relative risk (RR) 1.10, 1.07-1.14]. This result was true across many surgery types. Conclusions: Surgeon case-volume is independently associated with the likelihood of RBC transfusion across a broad range of surgical procedures. Future efforts should be directed towards studying and standardization of transfusion practices.