右美托咪定对老年患者围术期心血管事件发生的影响

Effect of dexmedetomidine on development of perioperative cardiovascular events in elderly patients

目的评价右美托咪定对老年患者围术期心血管事件发生的影响。方法择期全麻下行腹部或下肢手术老年患者48例，ASA分级Ⅱ或Ⅲ级，性别不限，年龄65～85岁，体重指数19.5～25.3 kg/m^2。采用随机数字表法分为2组（n＝24）：全麻组（G组）和右美托咪定＋全麻组（D组）。D组于麻醉诱导前静脉泵注右美托咪定，负荷剂量0.25 μg/kg，泵注时间10 min，以0.2 μg·kg^－1·h^-1持续泵注至术毕前30 min；G组静脉泵注等容量生理盐水。术前1 d、术后1和2 d时行动态心电图监测心率变异性，包括全部窦性R-R间期的标准差（SDNN）、每5 min R-R间期均值标准差（SDANN）、正常相邻R-R间期差值均方根（RMSSD）。记录术中心血管事件的发生情况及血管活性药物的使用情况；记录术后2 d内心血管事件的发生情况。结果与G组比较，D组术后1和2 d时SDNN和SDANN、术后2 d时RMSSD升高，术中心血管事件总发生率及血管活性药物总使用次数降低，术后2 d内心血管事件总发生率降低（P〈0.05）。结论右美托咪定可减少老年患者围术期心血管事件的发生。

Objective To evaluate the effects of dexmedetomidine on the development of perioperative cardiovascular events in elderly patients.Methods Forty-eight patients of both sexes, aged 65-85 yr, with body mass index of 19.5-25.3 kg/m^2, of American Society Anesthesiologists physical status Ⅱ or Ⅲ, scheduled for elective abdominal or lower limb surgery under general anesthesia, were divided into 2 groups（n=24 each）using a random number table： general anesthesia group（group G）and dexmedetomidine plus general anesthesia group（group D）. In group D, dexmedetomidine was intravenously infused in a loading dose of 0.25 μg/kg over 10 min and then continuously infused at 0.2 μg·kg^-1·h^-1 until 30 min before the end of surgery.The equal volume of normal saline was intravenously infused instead in group G. At 1 day before surgery and 1 and 2 days after surgery, dynamic electrocardiogram was used to monitor heart rate variability including standard deviation of normal-to-normal intervals, standard deviation of the average 5-min normal-to-normal intervals, and root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals.The development of intraoperative cardiovascular events and requirement for vasoactive drugs were recorded, and the development of cardiovascular events within 2 days after surgery was also recorded.Results Compared with group G, standard deviation of normal-to-normal intervals and standard deviation of the average 5-min normal-to-normal intervals at 1 and 2 days after surgery and root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals at 2 days after surgery were significantly increased, the total incidence of intraoperative cardiovascular events and requirement for vasoactive drugs were decreased, and the total incidence of cardiovascular events within 2 days after surgery was decreased in group D（P 〈0.05）.Conclusion Dexmedetomidine can reduce the development of perioperative cardiovascular events in elderly patients.