A randomised controlled trial of dexmedetomidine for suspension laryngoscopy

This is the authors' abstract. We don't add key points for this paper.

We randomly allocated 80 patients to intravenous dexmedetomidine (0.25, 0.5, or 1 μg.kg(-1) ) or placebo 15 min before anaesthetic induction. Dexmedetomidine 0.5 and 1.0 μg.kg(-1) significantly reduced the mean (95% CI) propofol effect-site concentrations by 0.83 (0.63-1.03) μg.ml(-1) , p = 0.001 and 1.29 (1.12-1.46) μg.ml(-1) , p = 0.0003 at intubation, by 1.05 (0.85-1.25 μg.ml(-1) , p = 0.0006 and 1.33 (1.15-1.51) μg.ml(-1) , p = 0.0002 when surgery started, and by 0.59 (0.39-0.79) μg.ml(-1) , p = 0.030 and 0.72 (0.57-0.87) μg.ml(-1) , p = 0.004 on completion of surgery, respectively. Patients' tracheas were extubated sooner after 0.5 and 1.0 μg.kg(-1) dexmedetomidine, by 5.36 (2.39-8.32) min, p = 0.009 and 7.37 (3.24-11.51) min p = 0.003, respectively. Tachycardic responses to intubation were present in five placebo patients and no dexmedetomidine patients. Bradycardia was treated after dexmedetomidine in six patients: five after 1.0 μg.kg(-1) ; and one after 0.25 μg.kg(-1) . Single-dose dexmedetomidine can reduce anaesthetic requirements, with both desirable and undesirable haemodynamic effects.