Intraoperative dexmedetomidine reduces postoperative sleep disturbance in older adults undergoing major abdominal...

Postoperative sleep disturbance (PSD) after major abdominal surgery in older adults is common and impairs recovery. Dexmedetomidine is a selective α₂-adrenergic agonist with sedative, analgesic, and anti-inflammatory properties that promotes natural sleep. We hypothesized that intraoperative dexmedetomidine would reduce PSD in this population.

In this randomized, double-blind, placebo-controlled trial, 210 older adults undergoing major abdominal surgery were randomly assigned (1:1:1) to receive intraoperative normal saline, dexmedetomidine 0.3 μg/kg/h, or 0.6 μg/kg/h. The primary outcome was PSD on the first postoperative night (Athens Insomnia Scale score ≥ 6). Secondary outcomes included PSD on until nights 30; pain at 24 and 48 h; delirium and depressive symptoms within 7 days; and recovery quality on postoperative days 1‒3. Sleep patterns on nights 1 and 2 were assessed using wrist actigraphy. This trial was registered on the Chinese Clinical Trial Registry (Identifier: ChiCTR2300073163; principal investigator: Ke Peng; dated July 23, 2023; https://www.chictr.org.cn/showproj.html?proj=199410).

203 patients (median age 71 years; 67.5% male) completed this trial. Compared with normal saline (n = 67), both low-dose (n = 68) and high-dose dexmedetomidine (n = 68) significantly reduced first-night PSD (20.6% vs 65.7%; relative risk 0.31, 95% CI 0.19-0.50; NNT 2.2; P < 0.001; and 11.8% vs 65.7%; relative risk 0.18, 95% CI 0.09-0.34; NNT 1.8; P < 0.001, respectively). The two doses did not differ. Dexmedetomidine was associated with lower sleep disturbance on night 2 and higher recovery quality, without between-group differences in hypotension, bradycardia, delirium, or 30-day mortality. Exploratory actigraphy analysis (n = 20 per group) showed longer total sleep time and lower wake-time percentage associated with dexmedetomidine.

Intraoperative dexmedetomidine infusion reduced the relative risk of first-night PSD by 70-80% among older adults undergoing major abdominal surgery. These findings require confirmation in multicenter trials.