Comparison of prolongation of spinal anesthesia produced by intravenous dexmedetomidine and midazolam: A randomized control trial

Abstract

Context: Various intravenous (i.v.) adjuvants have been used along with spinal anesthesia to delay the onset of postoperative pain. Aims: To compare effects of i.v. dexmedetomidine with midazolam on duration of spinal anesthesia. Settings and Design: This prospective randomized control trial was conducted in a tertiary care institution. Subjects and Methods: Forty-three patients presenting for elective infraumbilical surgery under spinal anesthesia were randomly allocated into two groups. Group A received a loading dose of 0.5 μg/kg followed by 0.5 μg/kg/h of i.v. dexmedetomidine. Group B received a loading dose of 0.03 mg/kg followed by 0.03 mg/kg/h of i.v. midazolam. Two dermatomal regressions, regression to S 1 level, and sedation score were noted. Statistical Analysis Used: To test the statistical significance of duration of sensory blockade, Mann–Whitney U-test was applied. The incidence of bradycardia and hypotension was analyzed using Pearson's correlation coefficient test. Results: The mean time for two dermatomal regressions was significantly prolonged in Group A (2.3 ± 0.4 h) than Group B (1.6 ± 0.5 h, P = 0.001). Mean time for sensory regression to S 1 dermatome was also prolonged in Group A (5.2 ± 0.83 h) than in Group B (4.4 ± 0.87 h, P = 0.01). Glycopyrrolate was administered in 45% of patients in Group A and 21% in Group B, which was statistically significant ( P = 0.039). Conclusion: Conscious sedation with i.v. dexmedetomidine at a loading dose of 0.5 μg/kg followed by 0.5 μg/kg/h prolongs duration of spinal anesthesia than i.v. midazolam at a loading dose of 0.03 mg/kg followed by 0.03 mg/kg/h in patients undergoing infraumbilical surgeries. However, dexmedetomidine is associated with higher incidence of hemodynamic instability.

Comparison of the effect of dexmedetomidine and midazolam under spinal anesthesia for cesarean delivery: a randomized controlled trial, single center study in South Korea

“…However, in this study, we did not observe prolongation of the block compared to midazolam. Sivachalam et al [ 15 ] compared the effects of dexmedetomidine and midazolam on the duration of spinal anesthesia and found a prolonged mean time for two dermatomal regressions with dexmedetomidine. We used only the loading dose and measured the sensory recovery time to the T10 sensory level and not the two-level regression time.…”