Association between perioperative blood transfusion and early postoperative cognitive dysfunction in aged patients following total hip replacement surgery

Introduction. Accumulating evidence suggests that enhanced inflammatory responses contribute to the pathogenesis of postoperative cognitive dysfunction (POCD). Blood transfusion can trigger an enhancement of acute inflammatory responses. Therefore, we hypothesized that perioperative blood transfusion is associated with a higher risk of POCD in aged patients following total hip replacement surgery. Material and methods. Patients older than 65 years undergoing elective total hip replacement surgery were enrolled from October 2011 to December 2012. Neurocognitive tests were evaluated at baseline and at 7 d after surgery by a Mini-Mental State Test. Multivariate logistic regression analysis was used to determine risk factors associated with POCD. Results. Fifty-six patients (27.3%) developed POCD 7 d postoperatively. Patients who developed POCD were older, had a lower education level and preoperative hemoglobin concentration, had more blood loss, and had a lower body weight (p < 0.05). Patients with POCD were more likely to receive red blood cells (RBCs) transfusion (51.8% versus 31.5%; p < 0.05). A multivariable logistic regression model identified older age, lower education level, and perioperative blood transfusion of more than 3 units as independent risk factors for POCD 7 d postoperatively. Conclusion. Our data suggested that perioperative blood transfusion of more than 3 units of RBCs is an independent risk factor for POCD in aged patients following total hip replacement surgery.