Katoh T, Suguro Y, Nakajima R, Kazama T, Ikeda K
Department of Anesthesiology and Critical Care Medicine, Hamamatsu University School of Medicine.
Br J Anaesth. 1992 Sep;69(3):259-62. doi: 10.1093/bja/69.3.259.
We studied 16 healthy ASA physical status I patients (aged 13-71 yr for sevoflurane and 22-74 yr for isoflurane) to determine maximum blood concentrations on awakening (MBCawake) from sevoflurane and isoflurane anaesthesia, and determined if age and duration of anaesthesia significantly influenced MBCawake. After operation, the end-tidal concentration of anaesthetics was decreased gradually. During recovery from anaesthesia, patients were asked repeatedly to open their eyes. We obtained blood samples to measure the anaesthetic concentration when patients first opened their eyes. MBCawake of sevoflurane and isoflurane (ml of anaesthetic gas per ml of blood) were 0.40 (SE 0.04)% and 0.53 (0.04)%, respectively. MBCawake values of sevoflurane and isoflurane correlated significantly with age (P < 0.05) but not with duration of anaesthesia. Blood:gas partition coefficients of sevoflurane and isoflurane were 0.65 (SD 0.05) and 1.36 (0.09), respectively. There was no significant correlation between age and blood:gas partition coefficient for sevoflurane and isoflurane. Awakening alveolar concentrations (MACawake) calculated from MBCawake were 0.61 (SE 0.05)% for sevoflurane and 0.39 (0.02)% for isoflurane, and correlated significantly with age. The ratios of awakening alveolar concentration to MAC were reasonably constant--0.33 for sevoflurane and 0.33 for isoflurane.
我们研究了16例健康的美国麻醉医师协会（ASA）身体状况I级患者（七氟醚组年龄为13 - 71岁，异氟醚组年龄为22 - 74岁），以确定七氟醚和异氟醚麻醉苏醒时的最大血药浓度（MBCawake），并确定年龄和麻醉持续时间是否显著影响MBCawake。术后，麻醉药的呼气末浓度逐渐降低。在麻醉恢复过程中，反复要求患者睁眼。当患者首次睁眼时，我们采集血样以测量麻醉药浓度。七氟醚和异氟醚的MBCawake（每毫升血液中麻醉气体的毫升数）分别为0.40（标准误0.04）%和0.53（0.04）%。七氟醚和异氟醚的MBCawake值与年龄显著相关（P < 0.05），但与麻醉持续时间无关。七氟醚和异氟醚的血/气分配系数分别为0.65（标准差0.05）和1.36（0.09）。七氟醚和异氟醚的年龄与血/气分配系数之间无显著相关性。由MBCawake计算得出的苏醒肺泡浓度（MACawake），七氟醚为0.61（标准误0.05）%，异氟醚为0.39（0.02）%，且与年龄显著相关。苏醒肺泡浓度与MAC的比值相当恒定——七氟醚为0.33，异氟醚为0.33。
