关节腔注射右美托咪定联合罗哌卡因对膝关节镜术后镇痛剂量效应的前瞻性随机对照研究

目的 探讨膝关节镜术后关节腔内注射不同剂量的右美托咪定联合罗哌卡因的镇痛效果。方法 采用前瞻性随机双盲对照研究,纳入2015年6月—2016年12月在蚌埠医学院第一附属医院择期行膝关节镜手术患者90例,其中男56例、女34例,年龄18~63岁;膝关节游离体54例,半月板损伤36例。按数字表法随机分为三组,每组30例。手术结束时关节腔分别注射镇痛药:罗哌卡因组(R组)为0.25%罗哌卡因14 mL+生理盐水1 mL;低剂量右美托咪定联合罗哌卡因组(RD1组)为0.25%罗哌卡因14 mL+右美托咪定0.5 μg/kg加入生理盐水配成1 mL;高剂量右美托咪定联合罗哌卡因组(RD2组)为0.25%罗哌卡因14 mL+右美托咪定1.0 μg/kg加入生理盐水配成1 mL。记录和比较患者术后1、2、4、6、8、12、24 h静息时和运动时VAS,术毕至首次使用镇痛药时间,术后24 h内地佐辛用量以及相关不良反应。结果 三组患者的性别、年龄、体质量、身高、手术时间、手术方式等差异均无统计学意义(P值均>0.05)。静息和运动状态下,三组患者VAS术后1 h最低,逐渐升高,在术后8 h达高峰;各组术后不同时间VAS差异均有统计学意义(F=178.116、90.791,P值均<0.01);不同组间差异均有统计学意义(F=21.258、23.521,P值均<0.01);不同时点RD2组VAS均低于RD1组,RD1组均低于R组,其中术后1、2、4、6 h时点的VAS差异均有统计学意义(P值均<0.05),但术后8、12、24 h差异均无统计学意义(P值均>0.05)。RD1、RD2组患者术后首次使用镇痛药时间长于R组(P值均<0.05),RD2组术后首次使用镇痛药时间长于RD1组(P<0.05);24 h内总的地佐辛用量RD1、RD2组少于R组(P值均<0.05),RD2组少于RD1组(P<0.05)。三组患者术后24 h内,均无嗜睡、心动过缓、低血压、低氧血症及恶心呕吐等不良反应的发生。结论 关节腔内注射右美托咪定联合罗哌卡因对膝关节镜术后镇痛比单独使用罗哌卡因效果更佳,且镇痛效果与右美托咪定剂量有关。

Analgesic effect of intra-articular injection of dexmedetomidine combined with ropivacaine after arthroscopic knee surgery: a prospective,randomized and controlled trial

Objective To investigate the effect of intra-articular administration of dexmedetomidine combined with ropivacaine on postoperative analgesia after knee arthroscopy.Methods A prospective, randomized and controlled trial was conducted in 90 patients undergoing arthroscopic knee surgery from the First Affiliated Hospital of Bengbu Medical College from June 2015 to December 2016, including 54 patients of loose body of knee joint and 36 patients of meniscus injury. They were randomly divided into 3 groups, 30 patients in each group. At the end of the surgery, the analgesics were respectively injected into the articular cavity. Patients who were given the mixture of 14 mL of 0.25% ropivacaine and 1 mL normal saline served as the ropivacaine group (R group), and patients received the mixture of 14 mL of 0.25% ropivacaine and 0.5 μg/kg dexmedetomidine and 1 mL normal saline served as the low-dose dexmedetomidine and ropivacaine group (RD1 group), while patients received the mixture of 14 mL of 0.25% ropivacaine and 1.0 μg/kg dexmedetomidine and 1 mL normal saline served as the high-dose dexmedetomidine and ropivacaine group (RD2 group). Then the pain scores at rest and during movement were assessed with VAS at 1, 2, 4, 6, 8, 12, 24 h postoperatively. Moreover, the time to the first postoperative analgesic request, consumption of dezocine at 24 h after surgery and related adverse events were recorded and analyzed.Results There was no significant difference in gender, age, weight, height, operation time and the type distribution between the three groups (all P values>0.05). At rest and during movement, the VAS score of the three groups was the lowest at 1 h after the surgery and gradually increased, reaching the peak at 8 h after surgery; and the differences of VAS scores in different groups at different time points after surgery were statistically significant (F=178.116, 90.791, all P values<0.01); the differences between each two groups were statistically significant (F=21.258, 23.521, all P values<0.01). At different time points, VAS scores of RD2 group were lower than those of RD1 group, and RD1 group was lower than R group; meanwhile, the differences of VAS scores at 1, 2, 4, 6 h after surgery had statistical significance (all P values<0.05), but the difference at 8, 12, 24 h after surgery had no statistical significance (all P values>0.05). The time to the first postoperative analgesic request was longer in the RD1 group and RD2 group than that in the R group (all P values<0.05), and the RD2 group was longer than RD1 group (P<0.05). The consumption of dezocine at 24 h after surgery in the RD1 group and RD2 group was significantly less than that in the group R (all P values<0.05), and the RD2 group was less than the RD1 group (P<0.05). There was no adverse events, such as somnolence, bradycardia, hypotension, hypoxemia, nausea and vomiting, in the three groups within 24 h after surgery.Conclusions The analgesic effect of dexmedetomidine combined with ropivacaine on postoperative pain after arthroscopic knee surgery is better than that of ropivacaine alone, and the efficacy is in a dose-dependent manner.