Effect of WBC reduction of transfused RBCs on postoperative infection rates in cardiac surgery

BACKGROUND: WBC-replete blood transfusion has been suggested as an independent cause of increased postoperative infection. STUDY DESIGN AND METHODS: A total of 597 patients undergoing elective coronary artery or heart valve surgery were randomly assigned to receive plasma-reduced (PR), buffy coat-depleted (BCD), or WBC-filtered (WCF) RBCs in the event of requiring blood transfusion. Details of postoperative course were recorded. Further information was collected from the patient's general practitioner 3 months after discharge. RESULTS: No significant difference in inpatient infection rates was observed among patients randomly assigned to receive PR, BCD, or WCF RBCs. When only those receiving transfusion were analyzed (n = 509), use of PR RBCs was associated with more events coded as infections (p less than or equal to 0.05) compared with BCD or WCF RBCs. However, when events coded as urinary tract infections were excluded, there was no significant difference among the three groups. Follow-up performed after discharge showed no difference in readmission rates, but a higher reported rate of infection in those randomly assigned to receive WCF RBCs (p < 0.02). CONCLUSION: No evidence has been found, analyzed by intention to treat, that use of WBC-reduced, BCD, or WCF RBCs reduces postoperative inpatient infection in patients undergoing cardiac bypass surgery.