目的 探讨不同剂量右美托咪定复合布比卡因用于膝关节镜手术患者蛛网膜下腔阻滞的临床疗效.方法 选择2013年1 月-2015 年1 月胜利油田中心医院收治的择期行膝关节镜手术患者80 例,随机分为对照组,右美托咪定低、中、高剂量组,每组各20 例.经腰椎3-4 间隙行蛛网膜下腔穿刺,对照组给予0.75%布比卡因11.25 mg,右美托咪定低、中、高剂量组分别在对照组的基础上给予盐酸右美托咪定注射液5、10、15 μg.观察各组感觉、运动阻滞起效及维持时间,到达最高感觉阻滞平面时间,腰麻维持时间,围术期不同时点患者血压、心率、意识状态变化及发生的不良事件.结果 右美托咪定低、中、高剂量组感觉平面达T10 时间(t₁)、达感觉阻滞最高平面时间(t₂)、运动阻滞达3 级时间(t₃)均显著短于对照组,高剂量组t₁、t₂、t₃ 时间均显著短于低、中剂量组,差异有统计学意义(P< 0.05).右美托咪定低、中、高剂量组感觉、运动阻滞时间,腰麻作用时间均显著长于对照组,且高剂量组长于低、中剂量组,差异有统计学意义(P< 0.05).大剂量组麻醉后15、30、60 min 时Ramsay 评分最高,显著高于其他3 组(P< 0.05).大剂量组患者心动过缓、低血压发生率最高,而寒战、恶心呕吐、头痛等发生率比较差异无统计学意义.结论 5、10、15 μg 右美托咪定复合布比卡因均能缩短感觉、运动阻滞起效时间,延长其阻滞维持时间,提供较好的麻醉效果.但15 μg 右美托咪定引起术中患者心动过缓、低血压的几率较高,需在密切监护下应用.

Objective To observe the effect of dexmedetomidine with different doses combined with bupivacaine on arthroscopic surgery in patients with subarachnoid block. Methods Patients (80 cases) who accepted arthroscopic surgery in Shengli Oilfield Central Hospital from January 2013 to January 2015 randomly divided into control, dexmedetomidine low-, mid-, and high-dose groups (20 cases in each group). Subarachnoid puncture was through the lumbar line 3-4 clearance, patients in the control group were given 0.75% bupivacaine 11.25 mg, the patients in the low-, mid-, and high-dose groups were respectively given Dexmedetomidine Hydrochloride Injection 5, 10, 15 μg on the basis of the control group. The sensory and motor block effect and maintain time, reached time of highest sensory blockade plane, maintain time of lumbar hemp, blood pressure, heart rate, consciousness change of different time in perioperative, and occurrence of adverse events in four groups were observed. Results The reached time of feel plane to T10 (t₁), reached time of highest sensory blockade plane (t₂), and reached time of motion block up to level 3 (t₃)in low-, mid-, and high-dose groups were significantly shorter than those in the control group. The t₁, t₂, and t₃ in the high-dose group were significantly shorter than those in the low-, mid-dose group, with significant difference (P < 0.05). Sensory and motor block time, lumbar hemp duration in the low-, mid-, and high-dose groups were significantly longer than those in the control group, and those observational indexes in high-dose groups were significantly longer than the low-, mid-dose group, with significant difference (P < 0.05). Ramsay score in the high-dose group was highest in 15, 30, and 60 min after anesthesia, which was significantly higher than those of other three groups (P < 0.05). The incidence of bradycardia and hypotension in the high-dose group was highest, and the incidence of chills, nausea and vomiting, and headache in four groups had no statistically significant difference. Conclusion Dexmedetomidine with 5, 10, 15 μg combined with bupivacaine can shorten the work time of sensory and motor blocked, and can extend the maintain time of block, which can provide good anesthetic effect. But the incidences of bradycardia and hypotension were high in patients with 15 μg dexmedetomidine, which should be applied under close monitoring.