右美托咪定混合低浓度罗哌卡因用于腹横肌平面阻滞的有效性及安全性

Dexmedetomidine mixed with low concentration of Ropivacaine in transversus abdominis plane block is safe and effective

目的观察右美托咪定混合低浓度罗哌卡因用于腹横肌平面阻滞的有效性及安全性。方法选择在全身麻醉下行腹腔镜结直肠癌根治术患者60例,所有患者术毕送麻醉恢复室(PACU)后在超声引导下行双侧腹横肌平面阻滞。采用随机数字表法,分成3组:0.19%罗哌卡因+生理盐水(19R组)、0.19%罗哌卡因+50μg右美托咪定(19RD组)及0.25%罗哌卡因+生理盐水(25R组),每组分别于两侧腹横肌平面注射药液各30 ml。所有患者术后均使用舒芬太尼静脉自控镇痛(PCIA)。比较3组患者术后2(T1)、4(T2)、8(T3)、12(T4)及24 h(T5)的Ramsay镇静评分、静息及咳嗽时疼痛评分(VAS评分);记录术后3组患者第1次需求PCIA距离手术结束时间(T);24 h镇痛泵PCIA请求与给药次数;不良反应发生的例数、术后镇痛满意度评分及发生局部麻醉药中毒的症状的例数。结果 3组患者不同时点的Ramsay镇静评分比较差异无统计学意义(P>0.05);与25R组比较,19R组静息时VAS评分在T1、T2、T3及T4时较高,19R组咳嗽时VAS评分在T1、T2及T3时较高,两组比较,差异有统计学意义(P<0.05)。19R组患者第1次镇痛泵PCIA请求距离手术结束时间(T)(16.9±13.1)h较25R组的(26.1±15.5)h缩短,差异有统计学意义(P<0.05);19R组患者24 h舒芬太尼PCIA总消耗量(V)、PCIA给药次数(D1)与PCIA请求次数(D2)与25R组比较,差异有统计学意义(P<0.05),19R组均高于25R组;19R组患者镇痛满意度评分与25R组比较,差异有统计学意义(P<0.05),19R组低于25R组;而19RD组与25R组比较,差异无统计学意义(P>0.05)。3组均未见腹横肌平面阻滞穿刺引起的不良反应或局部麻醉药中毒症状。结论超声引导下50μg右美托咪定混合低浓度(0.19%)罗哌卡因可安全有效地用于腹横肌平面阻滞,达到与0.25%罗哌卡因相当的镇痛效果,对腹腔镜结直肠癌根治术患者能提供有效镇痛,并能减少局部麻醉药中毒的风险。

Objective To evaluate the efficacy and safety of Dexmedetomidine as an adjuvant mixed with low concentration of Ropivacaine in transversus abdominis plane block in order to reduce the dose and the toxicity of the local anesthetics.Methods Sixty patients undergoing laparoscopic radical resection of colorectal cancer were enrolled in this prospective,randomized,double-blind controlled clinical study.The patients were randomly allocated to three groups(20 in each)and underwent bilateral transversus abdominis plane block under ultrasound guidance after surgery with 30 ml of different local anesthetic compounds:0.19%Ropivacaine and saline in group 19R,0.19%Ropivacaine plus 50μg Dexmedetomidine in group 19RD and 0.25%Ropivacaine with saline in group 25R.Patient-controlled intravenous analgesia(PCIA)with Sufentanil was provided to all the patients.The pain score of Visual Analogue Scale(VAS)at rest and at cough,and Ramsay sedation score were evaluated at 2,4,8,12 and 24 h after operation.The time from the end of surgery to the first demand of PCIA,the total demand and delivery of Sufentanil within 24 h after operation were recorded.The patient satisfaction and the adverse reactions were also recorded.Results Ramsay sedation scores of the three groups at different time points were not significantly different(P>0.05).Comparing to the group 25R,VAS score at rest was significantly higher at 2,4,8 and 12 h after surgery in the group 19R(P<0.05),and VAS score during coughing was higher at 2,4 and 8 h after surgery in the group 19R(P<0.05).The time from the end of surgery to the first PCIA demand after surgery was significantly shorter in the group 19R comparing to that in the group 25R[(16.9±13.1)h vs.(26.1±15.5)h,P<0.05].The consumption of Sufentanil within 24 h after operation,PCIA administration times and demand in the group 19R were all significantly higher than those in the group 25R(P<0.05).But comparing these between the group 19RD and the group 25R,there were no significant differences(P>0.05).The incidence of postoperative nausea and vomiting was not significantly different among the three groups.There were no complications associated to transversus abdominis plane block or local anesthetic toxicity in any group.Conclusions Mixed with 50μg Dexmedetomidine,low concentration(0.19%)of Ropivacaine provides as effective block as 0.25%Ropivacaine in ultrasound-guided transversus abdominis plane block,and might reduce the risk of toxicity of Ropivacaine by reducing its dose for post-operative analgesia in patients receiving laparoscopic colorectal surgery.