Effects of dexmedetomidine on dynamic lung compliance in general anesthesia with desflurane: A randomized controlled study

OBJECTIVE: The aim of this study was to evaluate the effect of dexmedetomidine on lung compliance in patients under general anesthesia with desflurane. METHODS: This prospective, randomized, double-blind, controlled trial included 51 patients who received general anesthesia undergoing lower limb fracture surgery. Participants were assigned to either the experimental (loading dose of 0.25 μg/kg dexmedetomidine over 10 min, followed by a maintenance dose of 0.3 μg/kg/h until the end of the surgery) or control (0.9% saline) group. Anesthesia was maintained with desflurane, analgesics and muscle relaxants. The two groups were compared for hemodynamic parameters, dynamic lung compliance, oxygenation index, and postoperative complications. RESULTS: While dynamic lung compliance showed no significant difference between the two groups at T1 (P = 0.321), it was significantly higher in the experimental group at all other time points (all P < 0.001). In the control group, Cdyn at T4, T5, T6, and T7 were lower than that at T1 (P = 0.032, 0.043, 0.032 and 0.018, respectively). There were no significant between-group differences in the mean arterial pressure and heart rate. Compared to the control group, the experimental group had a higher oxygenation index at T1 (P < 0.001), T2 (P < 0.001), T3 (P < 0.001), T4 (P = 0.02), and T5 (P = 0.016) and significantly lower peak airway pressure at all time points (all P < 0.001). Both groups had comparable postoperative outcomes. CONCLUSIONS: Dexmedetomidine infusion at a loading dose of 0.25 μg/kg and maintenance dose of 0.3 μg/kg/h improved dynamic lung compliance in patients receiving desflurane during general anesthesia.