Association between preoperative anemia and postoperative delirium in elderly patients undergoing total hip arthroplasty with combined spinal-epidural anesthesia: A retrospective cohort study.

BACKGROUND

The effect of preoperative anemia on postoperative delirium (POD) risk in elderly patients undergoing total hip arthroplasty (THA) with spinal-epidural anesthesia remains unclear. This study aimed to evaluate the association of preoperative anemia and its severity on POD occurrence in this population.

METHODS

This retrospective cohort study included 609 patients aged ≥ 65 years who underwent their first elective total THA with CSE between January 1, 2020, and December 31, 2024. Patients were stratified by preoperative anemia status using WHO criteria as hemoglobin < 13 g/dL males and < 12 g/dL females. Anemia severity was further stratified into mild or moderate-to-severe categories using a hemoglobin cutoff of 11 g/dL. Inverse probability of treatment weighting (IPTW) was employed to adjust for potential confounders. The primary outcome was the incidence of postoperative delirium. The secondary outcomes included in-hospital deep vein thrombosis, pulmonary infection, surgical site infection, and length of hospital stay (LOS).

RESULTS

The overall POD incidence was 4.5 % (24/538). Moderate-to -severe anemia was significantly associated with increased POD risk (odds ratio [OR] 3.29; 95 % confidence interval [CI], 1.21-8.96; P = 0.02). No statistically significant differences were observed for secondary outcomes between groups.

CONCLUSIONS

Moderate-to-severe preoperative anemia was significantly associated with an increased risk of postoperative delirium in elderly patients undergoing THA with combined spinal-epidural anesthesia. Further prospective studies are warranted to evaluate the efficacy of specific interventions aimed at correcting preoperative anemia in this patient population.