Comparison of the Sedative Effects of Dexmedetomidine and Midazolam for Critically Ill Patients

Objective:To compare the sedative effects of dexmedetomidine,midazolam,and the combination of them for critically ill patients in intensive care unit.Methods:Sixty patients undergoing mechanical ventilation in intensive care unit were randomly devided into three groups:midazolam group(n=18),dexmedetomidine group(n=22),dexmedetomidine and midazolam combination group(n=20).Every patient in each group was waken up per 24 h.Midazolam group: an initial loading dose of 0.05 mg/kg midazolam was administered intravenously,maintenance load 0.02~0.08 mg/(kg·h);dexmedetomidine group: an initial loading dose of 1 μg/kg dexmedetomidine was administered intravenously,maintenance load 0.2~0.7μg/(kg·h);dexmedetomidine and midazolam combination group: an initial loading dose of 0.05 mg/kg midazolam was administered intravenously,maintenance load dexmedetomidine 0.2~0.7 μg/(kg·h).The time to achieve sedation as well as the alteration of the heart rate,oxygen saturation after 24 h,and the wake time after drug withdrawal have been recorded.Adverse reactions,C-reactive protein(CRP) in blood before sedation,24 h and 72 h after sedation have been detected.Results: Four patients in dexmedetomidine group have been observed decreased heart rate(60 bpm),and after drug withdrawal all of them were wakened up,no one showing respiratory depression.Six patients of midazolam group showed respiratory depression,and the average wake time after drug withdrawal was 40 min.Dexmedetomidine-midazolam combination group have not shown any respiratory and heart rate depression.The average time achieved satisfactory sedation in midazolam group was significantly shorter than that in dexmedetomidine group(P0.05).The average wake time after drug withdrawal in dexmedetomidine group was significantly shorter than that in midazolam group(P0.05)There was no significant change of CRP in midazolam group.The level of CRP in dexmedetomidine group and dexmedetomidine and midazolam combination group dropped significantly after drug infusion.Conclusions: Though the time to achieve satisfactory sedation state using dexmedetomidine is longer than midazolam,it has no adverse reaction,and the wake time after drug withdrawal is shorter as well.The sedation effect of midazolam is better than dexmedetomidine,but it can induce respiratory depression.Dexmedetomidine can relieve stress reaction.The combination of midazolam and dexmedetomidine will be a better way in sedation.