Effect of a Single-dose Dexmedetomidine on Postoperative Delirium and Intraoperative Hemodynamic Outcomes in Elderly Hip Surgery; A Randomized Controlled Trial Dexmedetomidine for Postoperative Delirium

Abstract

Objective: Postoperative delirium (POD) is common in elderly patients. The growing evidences suggesting the potential benefits of dexmedetomidine (DEX) infusion in reducing POD. However, the administration of a singledose DEX remains controversial. This study aims to investigate the effect of a single-dose DEX on POD in elderlypatients undergoing hip surgery. Materials and Methods: This prospective, randomized, double-blinded trial enrolled patients aged over 65 years who underwent hip surgery under spinal anesthesia. Patients were assigned to either the DEX (received intravenous DEX 0.3-0.5 μg/kg after incision), or the normal saline solution (NSS). Delirium assessments were conducted at the post anesthetic care unit (PACU) and at 24, 48 and 72 hours postoperatively using the Confusion AssessmentMethod (CAM). Results: A total of 200 patients were randomized, with 100 in the DEX and 100 in the NSS. The incidence of POD was significantly lower in the DEX compared to the NSS (P < 0.001, RR 0.45, 95%CI: 0.28, 0.73). This difference remained significant at each postoperative assessment time point. There was no significant difference in sedation score and perioperative hemodynamics, except for a slightly lower intraoperative heart rate (P=0.015) and systolic blood pressure (P=0.029) observed at the PACU in the DEX, but these differences were not clinically significant. Additionally, the length of stay after surgery in the DEX was significantly shorter compare to the NSS (P=0.006). Conclusion: A single-dose dexmedetomidine can reduce the incidence of POD within 72 hours postoperatively in elderly patients undergoing hip surgery without compromising intraoperative hemodynamic stability.