Allogeneic red blood cell transfusion is an independent risk factor for the development of postoperative bacterial infection

Background and Objectives: Allogeneic red blood cell transfusions may exert immunomodulatory effects in recipients including an increased rate of post operative bacterial infection. It is controversial whether allogeneic trans fusion is an independent predictor for the development of postoperative bac terial infection. Methods: We analysed a prospectively collected database o f 1,349 patients undergoing colorectal surgery in 11 centres across Canada. The primary outcome was the development of either a postoperative wound in fection or intraabdominal sepsis in transfused and nontransfused patients. The effect of allogeneic transfusion on postoperative infection was evaluat ed with adjustment for all the confounding factors in a multiple regression analysis. Results: The 282 patients who received a total of 832 allogeneic units had a significantly higher frequency of wound infections and intra-a bdominal sepsis than the patients who were not transfused (25.9 vs. 14.2%, p 0.001). A significant dose-response relationship between transfusion and infection rate was demonstrated. Multiple regression analysis identified al logeneic transfusion as a statistically significant independent predictor f or postoperative bacterial infection (OR 1.18, 95% CI 1.05-1.33, p = 0.007) . Other independent predictors were anastomotic leak, repeat operation, pat ient age and preoperative haemoglobin level. The mortality rate was also si gnificantly higher in the transfused group. Conclusion: These data support the hypothesis that allogeneic red cell transfusion is an independent risk factor for the development of postoperative bacterial infection in patients undergoing colorectal surgery. This association provides further reason to minimise exposure to allogeneic transfusions in the perioperative setting. Copyright (C) 2000 S. Karger AG, Basel.