老年病人术前靶控输注异丙酚镇静不同监测指标的比较

Comparison between Parameters used to Estimate the Depth of Anesthesia during Propofol Sedation with Target Controlled Infusion in Elderly Patients Peroperation

目的：观察在无手术刺激状态下,老年患者靶控输注异丙酚不同镇静程度与效应部位血药浓度（CE）、脑电双频指数（BIS）、平均动脉压（MAP）及心率（HR）的相关性。方法：择期老年手术患者18例,年龄65～78岁,ASAⅠ～Ⅱ级,所行手术不限。全麻诱导前行异丙酚靶控输注（TCI）镇静,靶浓度由0.5 mg/L开始,递增梯度为0.5 mg/L,间隔时间为5 min,直至镇静评分（OAA/S）为0后5 min停止。试验中,监测并记录患者的BIS、MAP、HR值,间隔20 s行OAA/S镇静评分。记录靶控输注系统预测的效应部位浓度值（CE）,每变化0.5 mg/L时的数值及时间。结果：①镇静深度的变化与CE、BIS、MAP呈线性回归关系：与CE呈负相关（r=-0.925,P〈0.01）,与BIS、MAP呈正相关（r=0.858,r=0.564;P均〈0.01）。相关性的程度依次为CE〉BIS〉MAP。HR与OAA/S的变化无显著相关性（P〉0.05）。②BIS能很好反映患者镇静深度的变化,可作为其监测的敏感指标。结论：效应部位的异丙酚浓度决定镇静程度的深浅及OAA/S评分的大小,作为新的麻醉镇静深度监测指标,BIS可很好地反映靶控输注异丙酚对老年患者的镇静程度,而作为传统的监测指标,MAP、HR受各种因素的影响较大,灵敏度较差。

Objective：To compare the relationship between the level of consciousness , the effect compartment concentration（Ce）,bispectral index （BIS）,MAP and HR during a step-by-step TCI of Propofol in the elderly patients before operation. Methods： Eighteen patients aged 65-78 year with ASA Ⅰ-Ⅱ who underwent elective surgery were studied. Patients with severe cardiovascu- lar disease and hearing disturbances were excluded. Premeditation consisted of Atropine 0. 01 mg/kg im 30 min before operation. The patients were sedated with Propofol given by TCI before general anesthesia. The target concentration （Ct） of Propofol was increased step-by-step with 0.5 mg/L each step until OAA/S sedation score became zero. At each step, Ct increased by 0.5 mg/L and the interval between the two steps was 5 min. During the test, the parameters were monitored and recorded simultaneously and correlated with OAA/S sedation every twenty. Results： The OAA/S score assumes the linear return relation with CE,BIS,MAP,assumes CE negative correlation（r=-0. 925,P〈0.01） ,with BIS/MAP positive correlation（r：0. 858,r=0. 564;P〈0.01）. The relevant degree is in turn CE〉 BIS〉MAP. There was not an obvious correlation between HR and OAA/S score. BIS was able to predict the depth of sedation and the sensitive index monitoring. Conclusion：The effect compartment concentration could decide the depth of sedation and OAA/S score. As a new type of monitoring indicator,BIS could reflect well on TCI in patients with the degree of sedation whereas the traditional indicators for monitoring, for example MAP and HR,subject to the influence of various factors larger, less sensitivity.