右美托咪定对老年人髋部手术后认知功能障碍的影响

摘要

目的：观察硬膜外麻醉复合不同剂量右美托咪定对老年人髋部手术后循环和认知功能障碍（POCD）的影响。方法选择2013年6月—2014年9月，65岁以上髋部手术患者120例，行硬膜外麻醉联合右美托咪定静脉泵注，按右美托咪定的泵注量不同，分为A组0.2μg·h-1·kg-1，B组0.4μg·h-1·kg-1和C组0.6μg·h-1·kg-1，每组40例。观察并记录3组患者入室时（T0）、用药后10 min（T1）、用药后20 min（T2）、停药即刻（T3）、停药后10 min（T4）以及手术完毕时（T5）的心率（HR）、平均动脉压（MAP）、血氧饱和度（SpO2）。应用简易智力状态量表（MMSE）测试3组患者术前24 h（t1）、术后12 h（t2）、术后24 h（t3）及术后72 h（t4）认知功能。结果3组患者在T0时MAP、HR及SpO2比较差异无统计学意义；C组T2、T3时HR和MAP均较A组、B组明显下降（均P<0.05）。3组术前MMSE评分差异无统计学意义，B组t2、t3时的MMSE评分均明显高于A组和C组（P<0.05）；B组POCD发生率明显低于A组和C组（P<0.05）。结论硬膜外麻醉复合右美托咪定以0.4μg·h-1·kg-1静脉泵注对老年患者的循环干扰小，可减少老年患者围手术期认知功能障碍的发生。%Objective To observe the effect of a variety dosage of dexmedetomidine on circulatory and cognitive func⁃tions in elderly patients who underwent hip orthopedic surgery. Methods A total of 120 patients who underwent hip ortho⁃pedic surgery, with age over 65 years old were recruited from 06/2013 to 09/2014 and were administered intravenously dex⁃medetomidine after epidural anesthesia. Based on the dosage of dexmedetomidine, patients were randomly divided into 3 groups with 40 cases in each group:Group A were given 0.2μg·h-1·kg-1 dexmedetomidine;Group B were given dexmedeto⁃midine 0.4μg · h-1 · kg-1, and group C were given 0.6μg · h-1 · kg-1. The heart rate (HR),mean arterial pressure (MAP), and pulse oxygen saturation (SpO2) were recorded at 6 time points, including the time entering operating room (T0), 10 min (T1), 20 min (T2) after drug administration, the time of drug withdrawal (T3), 10 min after drug withdrawal (T4) and the terminal time of surgery (T5) respectively. Cognitive function was evaluated by mini-mental state examination (MMSE) at the time points of 24 hours before surgery (t1), 12 hours (t2), 24 hours (t3), and 72 hours (t4) after surgery. Results All 3 groups of pa⁃tients show no significant difference of MAP, HR and SpO2 at T0 (P>0. 05).A significant decrease in MAP and HR were ob⁃served in Group C at T2 and T3 time points compared to those in Group A or Group B (P<0.05). There was no significant dif⁃ference in MMSE at time point T1 among all three groups (P > 0.05). However, compared to that in group A or group C, MMSE increased significantly at time point T2, T3 in group B (P<0.05). In addition, compared to group A or group C, the pa⁃tients in group B exhibited lower incidence of postoperative cognitive function disorder (P < 0.05). Conclusion Continu⁃ous intravenous infusion of Dexmedetomidine can be used in elderly patient who underwent hip orthopedic surgery at the dose of 0.4μg·h-1·kg-1 safely with little interference to circulatory and cognitive function in perioperative period.