实时监测下小流量和高浓度吸入麻醉给药方法的临床研究

Clinical study on inhalation anesthetic techniques with low-flow and high inspired concentration

目的 依据简单的数学公式和应用高精度的麻醉机和挥发罐 ,在监测下实施低流量吸入麻醉的方法。方法 随即选择 10例开颅、开胸、开腹手术的成年病人 ,气管内插管后 ,吸入异氟醚 ,挥发罐开在 5 % ,氧流量为 1L/min。连续监测吸入气 (F1)和呼出气 (FB)中的异氟醚浓度。每 10s由监测仪向微机传送一次数据并存入微机进行统计处理。吸药 10min后根据临床需要将FB 调控在某一水平。结果 吸入 10min后FB 可达 1 0 5 % ,并可用曲线或直线回归方程 :y =0 40 92 (Inx) +0 0 172 ,y =0 0 833x +0 1385 ,对此段时间内的实测值进行预测。曲线回归方程的预测精度讽刺地直线回归方程。但若采用分段直线回归方程 (y =0 0 6 87x +0 5 0 2 1)与 3min以后的曲线回归方程的预测精度相同。结论 采用低流量、高挥发罐输出可在 10min内完成吸入麻醉的诱导 ,并可根据简单的线性回归方程就可对呼出气中的药物浓度作出预测。

Objective Using accurate monitoring,and high precision anesthetic machine and vapourizer,and guided with a simple mathematics formula to implement low-flow inhaled anesthetic techniques.Methods Ten healthy patients under going craniotomy,thoracotomy or laparotomy were assigned to receive isoflurane by low-flor of fresh gas and high vapourizer output.After intubation,the vapourizer dial was set at 5% and the patients were delivered with 1L/min total fresh gas flow of oxygen.The expiratory(F E) and inspired(F 1) concentration of isoflurane were monitored continuously.The data were recorded with computer once every 10. The concentrations were plotted against the time and the predicted regression equation were calculated.Results The F E reached 1.05% 10 min after inhalation of isoflurane ,which could be predicted by curvilinear(y=0 4092(1nx)+0 0172) and lineal (y=0 083x+0 1385) regression equations from 1 to 10 min,The predicted concentration by curvilinear regression equation appeared to estimate the measured value more accurately than linear regression equation.However segmental lineal regression equation cluld predict the measured value as accurately as curvilinear regression equation.Conclusions The inhalation anesthetic induction can be completed within 10 min with low-flow of fresh gas flow and high output of vapourizer dial setting.The measured value of anesthetic can be predicted accurately.