Postoperative infusion of dexmedetomidine via intravenous patient-controlled analgesia for prevention of postoperative delirium in elderly patients undergoing surgery.

BACKGROUND: Postoperative delirium (POD) is a common clinical complication in elderly patients after surgery and predicts poor outcomes. AIM: We researched whether postoperative infusion of dexmedetomidine (DEX) had prophylactic effect on POD in elderly patients. METHODS: A total of 236 patients over the age of 60 years undergoing thoracoabdominal tumor surgery were enrolled in Zhejiang Cancer Hospital from November 2016 to October 2020. The patients were randomly assigned into DEX group (group D) and control group (Group C). DEX was provided via PCIA pump 1-3 days after surgery, which consisted of 3 ug/kg sufentanil and 3 ug/kg DEX in group D, and 3 ug/kg sufentanil without DEX in group C. The PCIA parameters were programmed as follows: total amount 150 ml, 2 ml bolus dose with a lock-out of 10 min and background infusion rate 2 ml/h. The primary endpoint was the incidence of POD, assessed twice daily within 7 days after surgery by Richmond Agitation-Sedation Scale (RASS) and the Confusion Assessment Method-Intensive Care Unit (CAM-ICU). The secondary endpoint was postoperative hospitalization days, ICU stay time, adverse events and non-delirium complications. RESULTS: The incidence of POD in all patients was 7%. The incidence of POD in group C was significantly higher than that in group D (10.1% vs 3.4%, P = 0.042). There were no significant differences in length of hospital stay after operation, ICU stay time, the percentage of patients discharged within 7 days after surgery, non-delirium complications, and 30-day all-cause deaths between the two groups. The incidence of hypertension in group D was lower than that in group C (P = 0.003), and there were no differences in other adverse events. CONCLUSION: Patients aged over 60 years received DEX in addition to intravenous patient-controlled analgesia (PCIA) for major thoracoabdominal surgery experienced less delirium.