腰硬联合麻醉下术中静脉右美托咪啶对术后硬膜外镇痛的影响

目的：观察腰硬联合麻醉下术中静脉持续输注0．5μg·kg-1．h-1的右关托咪啶对腹式全子宫切除术病人术后吗啡硬膜外自控镇痛（PCEA）的影响及相关不良反应发生的情况。方法：选择ASAI或II级、择期行腹式全子宫切除术病人50例，腰硬联合麻醉成功后，随机分为Ⅰ组（右关托咪啶组）和Ⅱ组（盐水对照组），每组25例，术后镇痛采用硬膜外镇痛。观察患者术后第一疼痛出现时间，术后24h和术后24--48h吗啡用量、PCEA泵按压次数和有效次数，VAS评分法评估患者术后不同时点的疼痛程度；记录围术期血流动力学的变化和血管活性药物的使用情况；记录镇痛期间恶心呕吐及皮肤瘙痒等不良反应的发生情况。结果：患者术后第一疼痛时间Ⅰ组较Ⅱ组延长（P〈0．05）；术后24小时吗啡用量、PCEA泵按压次数及有效按压次数Ⅰ组较Ⅱ组显著减少（P〈0．05），24---48小时两组病人无差异（P〉0．05）；病人术后0．5小时、6小时静息和运动VAS评分Ⅰ组较Ⅱ组显著减低（P〈0．05），其余时点无差异（P〉0．05）；麻醉后15min时Ⅰ组较Ⅱ组心率下降（P〈0．05），其余各时点比较无差异（P〉0．05），各时点平均动脉压两组无差异（P〉0．05）；阿托品和麻黄碱Ⅰ组使用量较Ⅱ组增多（P〈0．05）；恶心的发生率Ⅰ组较Ⅱ组降低（P〈0．05）。结论：腰硬联合麻醉下行腹式全子宫切除术，术中静脉持续输注0．5μg·kg-1．h-1的右美托咪啶可在术后24小时内减轻患者的疼痛反应，减少硬膜外镇痛吗啡的用量，且无明显不良反应。

The Effect of Intraoperative Infusion Dexmedetomidine for the Postoperative Epidural Analgesia

Objective： To investigate the effect of intraoperative infusion dexmedetomidine 0.5 μg-kg-1 .h1 to patient-controlled epidural analgesia （PCEA）. Methods： After the the spinal and epidural combined anesthesia succeed, 50 ASAⅠ - Ⅱ patients who were undergoing the total abdominal hysterectomy were randomized into group Ⅰ（dexmedetomidine group） and groups Ⅱ （placebo group）. All the patients achieved the patient-controlled epidural analgesia. The time to first administration ofpostoperation analgesia; The total mor- phine requirements, the number of unsatisfied demand and successfully delivered doses of PCEA during the first 24h and the second 24h was recorded. Postoperation pain was assessed using VAS. Hemodynamic,the dose of atropine and ephedrine used and the adverse reac- tion such as nausea, vomiting, pruritus were recorded. Results： The time to first administration ofpostoperation analgesia was longer in group Ⅰ than in group Ⅱ （P〈0.05）. The total morphine requirement, the number of unsatisfied demand and successfully delivered doses of PCEA in the first 24h was significantly less in group I than in group Ⅱ （P〈0.05）, while there were not different in the second 24h （P〉0.05）. The rest and motion VAS at 0.5 h and 6h was significantly lower in group I than in group Ⅱ （P〈0.05）, the other time points were not different （P〉0.05）. The heart rate, group I was slower than group Ⅱ in 15rain after anesthesia（P〈0.05 ）, there was on different in the other time point （P 〉0.05）. There was no different of blood pressure in every time points （P 〉0.05）; the dose of atropine and ephedrine used, group I was more than in group Ⅱ （P〈0.05）, group I were significant lower than group Ⅱ in the incidence of nausea （P〈0.05）. Conclusion： Undergone the spinal and epidural combined anesthesia ,for the total abdominal hysterectomy, in, intraoperative intravenouse dexmedetomidine 0.5μg. kg-1h-1 can reduce pain reaction and have the morphine-sparing effect in the first 24h period, and not significant adverse reaction.