Effect of infusion of low-dose dexmedetomidine combined with adductor canal block on quality of recovery after unilateral total knee arthroplasty in elderly patients: a prospective randomized controlled trial

Postoperative pain and adverse reactions after total knee arthroplasty (TKA) may hinder recovery. Adductor canal block (ACB) offers pain relief while preserving motor function, and dexmedetomidine (DEX) as an adjunct anesthetic helps reduce pain, inflammation, and stress. This study explores the effect of low-dose DEX infusion combined with ACB on recovery quality after TKA under enhanced recovery protocols. This double-blind, randomized controlled trial enrolled 110 elderly patients (65 to 80 years) scheduled for unilateral total knee arthroplasty. Participants were randomly assigned to either an intervention group or a control group. The intervention group received low-dose DEX infusion combined with ACB, while the control group received neither DEX infusion nor ACB. The primary outcome was the Quality of Recovery-15 scale (QoR-15) score at 24 h postoperatively. The intervention group had a higher QoR-15 score than the control group (123.68 ± 6.87 vs. 115.69 ± 6.10), with a mean difference of 8.1 points (95% CI 5.5–10.7; P < 0.001). Except for psychological support, the scores in the other four aspects of the QoR-15 were statistically different between the two groups (P < 0.05). Furthermore, we also observed reduced oral morphine equivalent consumption in the first 24 h postoperatively (P < 0.05) and a lower incidence of adverse events in the intervention group (P < 0.05). In elderly patients undergoing unilateral TKA, the intraoperative low-dose infusion of DEX combined with ACB can effectively improve the QoR and promote early rapid rehabilitation. This is associated with improved postoperative analgesia and reduced adverse reactions.