Dexmedetomidine decreases cerebral hyperperfusion incidence following carotid stenting: A double-blind, randomized...

Cerebral hyperperfusion syndrome (CHS) is a severe complication after carotid artery stenting (CAS). Dexmedetomidine (Dex) is an α₂ adrenoceptor agonist with sedative, analgesic, and neuroprotective properties. This randomized, double-blind, placebo-controlled trial (ChiCTR1900024416) aims to investigate whether prophylactic low-dose Dex decreases CH-induced brain injury following CAS.

After obtaining written informed consent, patients aged 18-80 who underwent CAS were enrolled between July 2019 and October 2022. Patients were randomly assigned to receive either intravenous Dex (0.1 μg/kg/h, until post-operative day 3) (n = 80) or placebo (normal saline) (n = 80). The primary endpoint was the incidence of CH and CHS assessed up to the third post-operative day. The secondary endpoints included National Institute of Health Stroke Scale (NIHSS) and Modified Rankin Scale (mRS) scores within 30 days of operation, extubation time, discharge from the hospital within 7 days post-operation, length of hospital stay post-operation, and all-cause 30-day mortality. Blood samples were collected before and after surgery for lipidomics, brain-derived neurotrophic factor (BDNF), and neurofilament light chain (Nfl) measurements. Acceptability, safety, and efficacy were evaluated by Cox model and logistic model.

CH occurred in 30 (37.5%) of 80 patients who received a placebo compared to 9 (11.2%) of 80 patients given Dex (prevalence: odds ratio [OR]: 0.21, 95% confidence interval [CI]: 0.088-0.467; p < 0.001; incidence: hazard ratio [HR]: 0.27, 95% CI: 0.14-0.50; p < 0.001). CHS was significantly higher in the placebo group (13.75%) than in the Dex group (2.5%) (prevalence: [OR]: 0.161, 95% CI: 0.024-0.626; p = 0.020; incidence: [HR]: 0.17, 95% CI: 0.06-0.52; p = 0.009). Dex significantly upregulated BDNF, decreased Nfl, and uniquely increased lysophosphatidylethanolamine.

A low prophylactic dose of Dex significantly reduced the incidence of CH and CHS up to 72 h after CAS.

This work was funded by National Natural Science Foundation of China (no. 82271288) and the Henan Provincial Science and Technology Research Project (nos. 242300421192 and JQRC2023004).