Kaur Sarabjit, Attri Joginder Pal, Kaur Gagandeep, Singh Tejinder Pal
Department of Anesthesia, Government Medical College, Amritsar, Punjab, India.
Saudi J Anaesth. 2014 Oct;8(4):463-9. doi: 10.4103/1658-354X.140838.
Various adjuvant are being used with local anesthetics for prolongation of intra operative and postoperative analgesia in epidural block for lower limb surgeries. Dexmedetomidine, the highly selective α2 adrenergic agonist is a new neuroaxial adjuvant gaining popularity. The aim of the present study was to compare the hemodynamic, sedative and analgesia potentiating effects of epidurally administered dexmedetomidine when combined with ropivacaine.
The study was conducted in prospective, randomized double-blind manner in which 100 patients of American Society of Anesthesiologist Grade I and II in the age group of 20-65 years of either sex under going lower limb surgeries were included after taking informed consent. The patients were randomly allocated into two groups of 50 each. Epidural anesthesia was given with 150 mg of 0.75% ropivacaine in Group A (n = 50) and 150 mg of 0.75% ropivacaine with dexmedetomidine (1 μg/kg) in Group B (n = 50). Two groups were compared with respect to hemodynamic changes, block characteristics which included time to onset of analgesia at T10, maximum sensory analgesic level, time to maximum sensory and motor block, time to regression at S1 dermatome and time to the first dose of rescue analgesia for 24 h. At the end of study, data was compiled and analyzed statistically using Chi-square test, Fisher's exact test and Student t-test. P < 0.05 was considered to be significant and P < 0.001 as highly significant.
Significant difference was observed in relation to the duration of sensory block (375.20 ± 15.97 min in Group A and 535.18 ± 19.85 min in Group B [P - 0.000]), duration of motor block (259.80 ± 15.48 min in Group A and 385.92 ± 17.71 min in Group B [P - 0.000]), duration of post-operative analgesia (312.64 ± 16.21 min in Group A and 496.56 ± 16.08 min in Group B [P < 0.001]) and consequently low doses of rescue analgesia in Group B (1.44 ± 0.501) as compared to Group A (2.56 ± 0.67). Sedation score was significantly more in Group B in the post-operative period.
Epidural Dexmedetomidine as an adjuvant to Ropivacaine is associated with prolonged sensory and motor block, hemodynamic stability, prolonged postoperative analgesia and reduced demand for rescue analgesics when compared to plain Ropivacaine.
在下肢手术的硬膜外阻滞中，各种辅助药物正与局部麻醉药联合使用，以延长术中及术后镇痛时间。右美托咪定是一种高度选择性的α2肾上腺素能激动剂，是一种新的神经轴索辅助药物，正逐渐受到欢迎。本研究的目的是比较硬膜外给予右美托咪定与罗哌卡因联合使用时的血流动力学、镇静和镇痛增强效果。
本研究采用前瞻性、随机双盲方式进行，纳入100例年龄在20 - 65岁、美国麻醉医师协会分级为I级和II级、接受下肢手术的患者，均签署知情同意书。患者被随机分为两组，每组50例。A组（n = 50）给予150 mg 0.75%罗哌卡因进行硬膜外麻醉，B组（n = 50）给予150 mg 0.75%罗哌卡因加右美托咪定（1 μg/kg）。比较两组的血流动力学变化、阻滞特征，包括T10节段镇痛起效时间、最大感觉镇痛平面、最大感觉和运动阻滞时间、S1皮节恢复时间以及24小时内首次使用补救镇痛药物的时间。研究结束时，收集数据并使用卡方检验、Fisher精确检验和学生t检验进行统计学分析。P < 0.05被认为具有统计学意义，P < 0.001被认为具有高度统计学意义。
两组在感觉阻滞持续时间（A组为375.20 ± 15.97分钟，B组为535.18 ± 19.85分钟[P = 0.000]）、运动阻滞持续时间（A组为259.80 ± 15.48分钟，B组为385.92 ± 17.71分钟[P = 0.000]）、术后镇痛持续时间（A组为312.64 ± 16.21分钟，B组为496.56 ± 16.08分钟[P < 0.001]）方面存在显著差异，因此与A组（2.56 ± 0.67）相比，B组的补救镇痛药物剂量较低（1.44 ± 0.501）。术后B组的镇静评分显著更高。
与单纯罗哌卡因相比，硬膜外右美托咪定作为罗哌卡因的辅助药物，可延长感觉和运动阻滞时间，维持血流动力学稳定，延长术后镇痛时间，并减少补救镇痛药物的需求。
