围术期输注右美托咪定对全麻术后镇痛药吗啡用量的影响

Effects of Dexmedetomidine on Morphine Demanding during Postoperative Analgesia

目的:观察围术期输注右美托咪定(Dexmedetomidine,Dex)对全麻术后镇痛药吗啡用量的影响。方法:选择40例ASAⅠ～Ⅱ级,拟在全麻下行全子宫切除术的患者,随机分为对照组(NS组)和右美托咪定(DEX)组。DEX组术前静脉给予右美托咪定负荷剂量1μg/kg,继以4μg/h持续输注至术后48h。NS组给予同等容量的生理盐水以同样技术予以输注。术后应用吗啡静脉自控镇痛(PCIA),记录患者首次要求镇痛的时间(患者主观VAS评分大于4cm时),术后4、8、18、24、48h疼痛评分(VAS),镇静评分(OAA/S),吗啡用量及术后恶心呕吐情况。结果:从手术结束到患者首次要求镇痛的时间,DEX组[(31.45±6.25)min]比NS组[(21.00±4.36)min]显著延长(P<0.01)。DEX组术后48h内吗啡的总用量(24.50±2.77)mg,显著低于NS组(33.47±2.79)mg(P<0.01)。术后恶心呕吐的发生率DEX组与NS组分别为10%和25%(P<0.05)。结论:全麻下行子宫切除术的患者,围术期输注DEX可延长患者术后首次要求镇痛的时间,减少术后48h内吗啡的用量及术后恶心呕吐的发生率。

Objeetive..To observe effects of dexmedetomidine（Dex）on the morphine requiement during postoperative analgesia. Methods：Forty ASA Ⅰ-Ⅱ undergoing elective abdominal hysterectomy with general anesthesia adult pa- tients were randomly divided to 2 groups： group 1 normal saline group（NS）, n1=20, group 2 dexmedetomidine（DEX）, n2 = 20, the patients in group DEX received Dex 1μg/Kg before start of surgery and 4μg/h for the next 48h. The pa- tients in group NS received the same volume of saline. Postoperative patient-controlled intravenous analgesia（PCIA） with morphine started when subjective pain intensity （visual analog scale, VAS）was〉4cm. VAS and sedation status （OAA/S） were assessed at 4,8,18,24 and 48h during postoperative period. Morphine consumption and complications during 48h after operation were recorded. Results：Morphine consumption was significantly lower in group DEX（24.50 ±2.77）rag than that in group NS（33.47±2. 79）rag in 48h PCIA（P〈0. 01）. The mean time to initiation of PCIA was significantly longer in group DEX（31.45±6. 25）min than that in group NS（21. 00±4. 36）min（P〈0. 01）. The inci- dence of postoperative nausea and vomiting was significantly less in group DEX（P〈0. 05）. Conclusion： Perioperative use of Dex intravenously significantly reduces postoperative morphine consumption and incidence of nausea and vomi- ting in the patients given PCIA.