Sharma Anshu, Varghese Nita, Venkateswaran Ramkumar
Department of Anaesthesiology, Kasturba Medical College, Manipal, Karnataka, India.
J Anaesthesiol Clin Pharmacol. 2020 Jul-Sep;36(3):381-385. doi: 10.4103/joacp.JOACP_323_17. Epub 2020 Sep 14.
Alpha-2 agonists such as dexmedetomidine when given intravenously or intrathecally as an adjuvant potentiate subarachnoid anesthesia. We studied the difference in subarachnoid anesthesia when supplemented with either intrathecal or intravenous dexmedetomidine.
Seventy-five patients posted for lower limb and infraumbilical procedures were enrolled for a prospective, randomized, double-blind, placebo-controlled study and divided into three groups: Group B ( = 25) received intravenous 20 mL 0.9%N aCl over 10 min followed by intrathecal 2.4 mL 0.5%bupivacaine + 0.2 mL sterile water; Group B ( = 25) received intravenous 20 mL 0.9%N aCl over 10 min followed by intrathecal 2.4 mL 0.5%b upivacaine + 0.2 mL (5 μg) dexmedetomidine; Group B ( = 25) received intravenous dexmedetomidine 1 μg/kg in 20 mL 0.9%N aCl over 10 min followed by intrathecal 2.4 mL 0.5%b upivacaine + 0.2 mL sterile water. Onset and recovery from motor and sensory blockade, and sedation score were recorded. Onset of sensory and motor blockade was assessed using Kruskal-Wallis test, whereas 2-segment regression and recovery was analyzed using ANOVA and Tukey's test to determine difference between the three groups. value <0.05 was considered statistically significant.
Although onset of sensory and motor block was similar in the three groups, motor recovery (modified Bromage scale 1) and two-segment sensory regression was prolonged in Group B > Group B > Group B ( < 0.001). Patients in Group B and Group B were sedated but easily arousable.
Intrathecal dexmedetomidine prolongs the effect of subarachnoid anesthesia with arousable sedation when compared with intravenous dexmedetomidine.
右美托咪定等α2激动剂在静脉或鞘内注射作为辅助用药时可增强蛛网膜下腔麻醉效果。我们研究了鞘内或静脉注射右美托咪定辅助蛛网膜下腔麻醉时的差异。
75例拟行下肢及脐下手术的患者纳入一项前瞻性、随机、双盲、安慰剂对照研究，分为三组：B组（n = 25）在10分钟内静脉输注20 mL 0.9%氯化钠溶液，随后鞘内注射2.4 mL 0.5%布比卡因+0.2 mL无菌水；B组（n = 25）在10分钟内静脉输注20 mL 0.9%氯化钠溶液，随后鞘内注射2.4 mL 0.5%布比卡因+0.2 mL（5μg）右美托咪定；B组（n = 25）在10分钟内静脉输注20 mL含1μg/kg右美托咪定的0.9%氯化钠溶液，随后鞘内注射2.4 mL 0.5%布比卡因+0.2 mL无菌水。记录运动和感觉阻滞的起效及恢复情况以及镇静评分。感觉和运动阻滞的起效采用Kruskal-Wallis检验评估，而采用方差分析和Tukey检验分析两阶段回归及恢复情况以确定三组之间的差异。P值<0.05被认为具有统计学意义。
尽管三组感觉和运动阻滞的起效相似，但B组> B组> B组运动恢复（改良Bromage评分1级）及两阶段感觉消退时间延长（P < 0.001）。B组和B组患者有镇静作用但易于唤醒。
与静脉注射右美托咪定相比，鞘内注射右美托咪定可延长蛛网膜下腔麻醉效果且具有可唤醒的镇静作用。
