关键词: 腰丛阻滞, 罗哌卡因, 右美托咪定, 地塞米松

Abstract: Objective To compare the clinical outcomes of dexmedetomidine versus dexamethasone in combination with ropivacaine used for lumbar plexus block. Methods A total of 90 adult patients undergoing unilateral knee or thigh surgery were divided into 3 groups： Control, dexmedetomidine and dexamethasone （30 cases in each group）. All patients received posterior lumbar plexus block guided by ultrasound and nerve stimulator, during which ropivacaine 0.375% in the volume of 0.5 mL/kg was injected in the control group, and the equivalent anesthetic plus dexamethasone 0.1 mg/kg or dexmedetomidine 1 μg/kg was injected in the other two groups. The onset time and duration of sensory, motor block were compared among groups. The VAS pain scores, dosage of analgesics and incidence of complications were recorded after surgery. Results The onset time of sensory and motor block in the two experimental groups were faster than that of group Control （P<0.05）, and the duration of sensory and motor block in the two experimental groups were longer than that of group Control （P<0.05）, with significant difference between group dexmedetomidine and group dexamethasone. The VAS pain scores and dosage of analgesics in the two experimental groupswere lower than those of group Control （P<0.05）, with lower values in group dexmedetomidine than in group dexamethasone. There was no significant difference in complications among the three groups （P>0.05）. Conclusion While mixed with ropivacaine for lumbar plexus block, both dexmedetomidine and dexamethasone can accelerate onset time of block, prolong block duration and reduce postoperative pain, with better outcomes provided by dexmedetomidine thanby dexamethasone.

Key words: lumbar plexus block, ropivacaine, dexmedetomidine, dexamethasone