Ishibe Y, Gui X, Uno H, Shiokawa Y, Umeda T, Suekane K
Department of Anesthesiology, Tottori University Faculty of Medicine, Japan.
Anesthesiology. 1993 Dec;79(6):1348-53. doi: 10.1097/00000542-199312000-00026.
In vitro studies have shown that isoflurane, enflurane, and halothane inhibit the hypoxic pulmonary vasoconstriction (HPV) with essentially the same potency. The aim of this study is to compare the effects of sevoflurane and isoflurane on HPV in constant-flow perfused rabbit lungs.
Constant-flow perfused lungs from Japanese white rabbits were tested. The lungs were divided into three groups: isoflurane alone (n = 6), sevoflurane alone (n = 6), and sevoflurane with ibuprofen pretreatment (n = 6). Baseline HPV responses were measured as the pulmonary arterial pressure increased after changing inspired oxygen concentration from 95% for 15 min to 3% (with 5% CO2) for 5 min without anesthetic administration. Next, three different concentrations of anesthetics were added to the inspired gas for 15 min in random order. The HPV response in the presence of anesthetic was expressed as a percentage of the pressor response in the absence of anesthetics, and dose-response relationships were calculated using the nonlinear least-squares method.
Isoflurane and sevoflurane both depressed the HPV response in a dose-related manner. The half-inhibition values (ED50) of HPV with isoflurane and sevoflurane were 0.85 +/- 0.22 MAC and 1.00 +/- 0.12 MAC (mean +/- SD), respectively, and were not statistically different. Ibuprofen pretreatment did not alter ED50 and slope of dose-response curve, although the absolute value of pressor response in the sevoflurane group with ibuprofen pretreatment was greater than that in the sevoflurane alone group at every concentration of sevoflurane.
Sevoflurane inhibits the HPV response in a dose-related manner, and its potency is similar to that of isoflurane in vitro. Cyclooxygenase products do not mediate the inhibition of HPV by sevoflurane.
体外研究表明，异氟烷、恩氟烷和氟烷抑制缺氧性肺血管收缩（HPV）的效力基本相同。本研究的目的是比较七氟烷和异氟烷对恒流灌注兔肺HPV的影响。
对日本白兔的恒流灌注肺进行测试。将肺分为三组：单独使用异氟烷组（n = 6）、单独使用七氟烷组（n = 6）和布洛芬预处理后使用七氟烷组（n = 6）。在未给予麻醉的情况下，将吸入氧浓度从95%持续15分钟改为3%（含5%二氧化碳）持续5分钟后，随着肺动脉压升高测量基线HPV反应。接下来，将三种不同浓度的麻醉剂随机添加到吸入气体中持续15分钟。麻醉状态下的HPV反应表示为无麻醉时升压反应的百分比，并使用非线性最小二乘法计算剂量-反应关系。
异氟烷和七氟烷均以剂量相关方式抑制HPV反应。异氟烷和七氟烷对HPV的半数抑制值（ED50）分别为0.85±0.22 MAC和1.00±0.12 MAC（平均值±标准差），且无统计学差异。布洛芬预处理未改变ED50和剂量-反应曲线的斜率，尽管在每个七氟烷浓度下，布洛芬预处理的七氟烷组升压反应的绝对值均大于单独使用七氟烷组。
七氟烷以剂量相关方式抑制HPV反应，其效力在体外与异氟烷相似。环氧化酶产物不介导七氟烷对HPV的抑制作用。
