The relationship between intraoperative blood transfusion and postoperative systemic inflammatory response syndrome

Background: Previous observations suggest that intraoperative blood transfusion (IBT) is a risk factor for adverse postoperative outcomes. IBT alters immune function and may predispose to systemic inflammatory response syndrome (SIRS). Methods: Patients in the American College of Surgeons National Surgical Quality Improvement Project database were studied over a 5-year period. Logistic regression identified predictors of SIRS. Propensity matching was used to obtain a balanced set of patients with equivalent preoperative risks for IBT. Results: Of 553,288 inpatients, 19,968 (3.6%) developed postoperative SIRS, and 40,378 (7.2%) received IBT. Mortality in patients with SIRS was 13-fold higher than in those without SIRS (13.5% vs 1.0%, P <.001). Multivariate analysis identified the amount of blood transfused during IBT as a significant predictor for development of SIRS (odds ratio, 2.2; P <.0001). After propensity matching, 33,507 matched patients with IBT had significantly increased risk for SIRS compared with non-SIRS matched patients (12.0% vs 6.5%, P <.001). Conclusions: There is a significant association between IBT and the development of SIRS. IBT may induce SIRS, and reductions in IBT may decrease the incidence of postoperative SIRS.