Evaluation of the relationship between sedation methods and postoperative delirium in geriatric patients operated with spinal anesthesia

Aims: With the rapidly aging population, the geriatric patient population is increasing, requiring a careful approach in anesthesia management. The comorbidities commonly seen in these patients often direct anesthetists towards regional anesthesia techniques; however, the adverse effects of certain sedative agents used during regional anesthesia on cognitive functions can create uncertainty about which agent should be preferred. In this context, our study aims to evaluate the effects of dexmedetomidine and remifentanil, administered for sedation in geriatric patients undergoing spinal anesthesia, on postoperative delirium. Methods: This prospective observational clinical study was conducted after obtaining ethical approval in patients aged 65 and older classified as American Society of Anesthesiologists (ASA) I-II-III who were planned for lower extremity surgery with spinal anesthesia. All patients underwent preoperative confusion assessment method (CAM) testing, and the cases were divided into two groups: dexmedetomidine group (group D, n=38) and remifentanil group (group R, n=38). After the completion of the surgery, sedation was discontinued, and the follow-up of the cases was maintained in the postoperative care unit until the modified Aldrete score reached 9. On the postoperative 24th hour, 72nd hour, and 30th day, the CAM test was repeated by the researcher who conducted the initial test. Results: No significant difference was found in postoperative delirium between the two different sedation protocols in the geriatric population (p>0.05). A statistically significant decrease in simultaneous mean arterial pressure (MAP) values was observed in group D patients at intraoperative 90, 105, 120, and 135 minutes (p<0.05). Conclusion: The effects of using dexmedetomidine and remifentanil as sedative agents in geriatric patients are similar regarding the frequency of postoperative delirium.