Carpenter R L, Eger E I, Johnson B H, Unadkat J D, Sheiner L B
Anesth Analg. 1986 Jun;65(6):575-82.
To determine the relative washin and washout characteristics of isoflurane, enflurane, halothane, and methoxyflurane, we administered all four anesthetics simultaneously (total = 1.1 MAC) to nine healthy patients for 2 hr. Concentrations of anesthetics in end-tidal gases were measured during washin and for 5-9 days during washout. Multiexponential (multicompartment) models were fit to the washin and washout curves using least-squares analysis. Slowly equilibrating compartments could only be identified during washout. For 27 of the 36 data sets, five-compartment models fit the washout curves significantly better than four-compartment models. The time constant for our first compartment is consistent with that predicted for washout of the lungs. Time constants for the second, third, and fifth compartments were consistent with current data for blood flows and solubilities of vessel-rich, muscle, and fat tissue groups, respectively. The fourth compartment has a time constant that lies between the time constants predicted for muscle and fat.
为了确定异氟烷、恩氟烷、氟烷和甲氧氟烷的相对吸入和洗出特性，我们对9名健康患者同时给予这四种麻醉剂（总量 = 1.1MAC），持续2小时。在吸入期间以及洗出期间的5 - 9天内，测量呼气末气体中麻醉剂的浓度。使用最小二乘法分析，将多指数（多室）模型拟合到吸入和洗出曲线。仅在洗出期间才能识别出平衡缓慢的室。在36个数据集中的27个，五室模型对洗出曲线的拟合明显优于四室模型。我们第一个室的时间常数与预测的肺洗出时间常数一致。第二、第三和第五个室的时间常数分别与目前关于富含血管组织、肌肉组织和脂肪组织组的血流和溶解度的数据一致。第四个室的时间常数介于预测的肌肉和脂肪的时间常数之间。
