年龄对Diprifusor靶控输注用于椎管内麻醉清醒镇静的影响

The influence of age on conscioussedation with DiprifusorTCI system in patients under regional anesthesia

目的 观察Diprifusor靶控输注 (TCI)用于不同年龄组椎管内麻醉清醒性镇静作用。方法 4 5例ASAⅠ～Ⅱ级、择期硬膜外麻醉和 /或腰麻的病人 ,按照年龄分为三组 ,每组 1 5例 :成年组 1 9～ 4 5岁、中年组 4 6～ 6 4岁和老年组 6 5～ 80岁。术中以DiprifusorTCI系统行丙泊酚清醒性镇静 ,采用 5分镇静评分法 ,根据病人反应及所需镇静水平调节靶浓度 (Ct)。Ct初设值为 0 4 μg/ml,每次调节量为 0 1 μg/ml,时间间隙不小于 3min。 结果 老年组病人镇静评分为 2、3和 4时丙泊酚Ct的ED50 分别为 0 6 3μg/ml、0 94 μg/ml和 1 2 8μg/ml,低于成年组 1 0 0 μg/ml、1 34μg/ml和1 6 6 μg/ml(P <0 0 1 )和中年组 0 80 μg/ml、1 1 0 μg/ml和 1 5 1 μg/ml(P <0 0 5 )。成年组和中年组的丙泊酚Ct的ED50 比较无显著差异。老年组病人镇静评分达 4时 ,有 5例 (33.3% )出现低血压及心动过缓 ,3例 (2 0 % )出现呼吸抑制 ,都高于成年组和中年组的发生率。结论 DiprifusorTCI系统可以用于椎管内麻醉清醒性镇静。但随着年龄的增加 ,椎管内麻醉清醒性镇静所需丙泊酚Ct降低 。

Objective To investigate the influence of age on the pharmacodynamics of Diprifusortarget controlled infusion (TCI) system used for conscioussedation in patients under regional anesthesia. Methods Forty five ASAⅠ Ⅱ patients (25 male,20 female) scheduled for elective surgery under epidural and/or spinal anesthesia were assigned to one of three groups( n= 15): the adult group(aged from 19 to 45 y) , the middle aged group(46 64y) and the elderly group(65 80y). Sedation evaluation was based on a standard five point scoring scale.Target concentration of propofol (Ct) started at 0 4μg/ml and altered by adjustment of 0 1μg/ml after equilibrium between target and calculated concentrations at least 3 min, until desired level of sedation (often scored 4) was reached. Results The ED 50 of Ctfor sedation in the elderly group at sedation level 2(drowsy), 3(drowsy, respondsto verbal stimulation) and 4(responds to physical stimulation only) were 0 63μg/ml, 0 94μg/ml and 1 28μg/ml respectively, which were obviously lower than those in adult group (1 00μg/ml, 1 34μg/ml and 1 66μg/ml, P< 0 01) and the middle aged group (0.80μg/ml, 1 10μg/ml and 1 51μg/ml, P< 0 05). There was no significantcorrelation between the adult group and the middle aged group. At sedation level 4 in the elderly group, 5(33 3%) patients were found exhibitinghypotension and bradycardia, 3(20%) with respiratory depression. These numbers were higher than those in the other two groups. Conclusion The feasibility of Diprifusor TCI system of propofol for conscious sedation in patients under regional anesthesia is clinically acceptable. Target concentration of propofol needed for conscious sedation decreases with more adverse events as the age of patients increases.