背景:各种佐剂,如吗啡,丁丙诺啡和芬太尼,可乐定,氯胺酮被用于麻醉实践,因为长期以来改善了脊柱麻醉后的围手术期镇痛。此类佐剂有助于诱导早期行走,但以其相关副作用为代价。因此,寻找有效的佐剂仍在进行中。目前右美托咪定,正在研究一种高选择性α2-肾上腺素受体激动剂在脊髓麻醉中的辅助作用。
目的:本研究旨在评估鞘内注射右美托咪定作为布比卡因的佐剂在脐下手术患者脊髓麻醉中的疗效。
方法:这是一个前瞻性的,在脊髓麻醉下进行脐下手术的60例患者的双盲研究。将患者随机分为2组(I组和II组),每组30例。第一组单独接受高压布比卡因(15mg),第二组接受高压布比卡因(15mg)和右美托咪定(5mcg)。感觉和运动阻滞的发病时间,感觉和运动阻滞的回归时间,镇痛持续时间,记录术中和术后的血流动力学参数。主要疗效参数是确定感觉阻滞的开始和持续时间,运动阻滞和术后镇痛持续时间。其次,还记录了任何相关的血流动力学变化和右美托咪定的不良反应。
方法:使用学生t检验和分类变量通过双尾Fisher精确检验或卡方检验分析连续数据。
结果:第二组感觉阻滞的发作时间为129.33±14.8秒,而第一组为208.33±19.18秒,第二组感觉阻滞的总持续时间为317.70±16.16分钟,第一组为188±11.86分钟。运动阻滞的发作时间分别为226.33±31.86分钟和320.33±29.81分钟,第II组和第I组的运动阻滞总持续时间分别为286.33±15.15分钟和166.5±12.11分钟。右美托咪定的镇痛时间为333.6±20.67分钟,布比卡因单药组的镇痛时间为193.67±7.06分钟。
结论:与单用布比卡因相比,在本研究中,右美托咪定作为佐剂显示感觉和运动阻滞的早期起效,镇痛持续时间和血流动力学稳定性更长。
BACKGROUND: Various adjuvants like morphine, buprenorphine and fentanyl, clonidine, ketamine are being used in anaesthetic practice since long for improvement of peri-operative analgesia following spinal anaesthesia. Such adjuvants have been helpful in induction of early ambulation but at the cost of their associated adverse effects. Therefore search for an effective adjuvant is still going on. Currently Dexmedetomidine, a highly selective α2-adrenoreceptor agonist is being studied for its adjuvant action in spinal anaesthesia.
OBJECTIVE: The present study aims to evaluate the efficacy of intrathecal Dexmedetomidine as an adjuvant to Bupivacaine in spinal anaesthesia in patients undergoing infra-umbilical surgeries.
METHODS: It was a prospective, double blind study among 60 patients undergoing infraumbilical surgeries under spinal anaesthesia. The patients were randomly allocated to 2 groups (Group I and Group II) of 30 each. Group I received hyperbaric bupivacaine (15 mg) alone and Group II received hyperbaric bupivacaine (15 mg) with Dexmedetomidine (5mcg). The onset time of sensory and motor block, regression time of sensory and motor block, duration of analgesia, haemodynamic parameters were recorded both intra and postoperatively. The primary efficacy parameters were to determine the onset and duration of sensory block, motor block and duration of postoperative analgesia. Secondarily any associated haemodynamic changes and adverse effects of Dexmedetomidine were also recorded.
METHODS: Continuous data were analysed using the Student\'s t-test and categorical variables by two-tailed Fisher-exact test or Chi-square test.
RESULTS: Onset of sensory block was 129.33±14.8 seconds in Group II as compared to 208.33±19.18 seconds in Group I with total duration of sensory block as 317.70±16.16 minutes in Group II and 188±11.86 minutes in Group I. Similarly, onset of motor block was 226.33±31.86 minutes and 320.33±29.81 minutes, with total duration of motor block as 286.33±15.15 minutes and 166.5±12.11 minutes in Group II and in Group I respectively. Duration of analgesia was 333.6±20.67 minutes with Dexmedetomidine but 193.67±7.06 minutes in bupivacaine alone group.
CONCLUSIONS: Dexmedetomidine as an adjuvant had shown early onset of sensory and motor block with longer duration of analgesia and haemodynamic stability in the present study as compared to bupivacaine alone.