Calzia E, Stahl W, Handschuh T, Marx T, Fröba G, Georgieff M, Rademacher P
Department of Anesthesiology, University of Ulm, Germany.
Anesthesiology. 1999 Mar;90(3):829-34. doi: 10.1097/00000542-199903000-00026.
During nitrous oxide (N2O) elimination, arterial oxygen tension (PaO2) decreases because of the phenomenon commonly called diffusive hypoxia. The authors questioned whether similar effects occur during xenon elimination.
Nineteen anesthetized and paralyzed pigs were mechanically ventilated randomly for 30 min using inspiratory gas mixtures of 30% oxygen and either 70% N2O or xenon. The inspiratory gas was replaced by a mixture of 70% nitrogen and 30% oxygen. PaO2 and carbon dioxide tensions were recorded continuously using an indwelling arterial sensor.
The PaO2 decreased from 119+/-10 mm Hg to 102+/-12 mm Hg (mean+/-SD) during N2O washout (P<0.01) and from 116+/-9 mm Hg to 110+/-8 mm Hg during xenon elimination (P<0.01), with a significant difference (P<0.01) between baseline and minimum PaO2 values (deltaPaO2, 17+/-6 mm Hg during N2O washout and 6+/-3 mm Hg during xenon washout). The PaCO2 value also decreased (from 39.3+/-6.3 mm Hg to 37.6+/-5.8 mm Hg) during N2O washout (P<0.01) and during xenon elimination (from 35.4+/-1.6 mm Hg to 34.9+/-1.6 mm Hg; P< 0.01). The deltaPaCO2 was 1.7+/-0.9 mm Hg in the N2O group and 0.5+/-0.3 mm Hg in the xenon group (P<0.01).
Diffusive hypoxia is unlikely to occur during recovery from xenon anesthesia, probably because of the low blood solubility of this gas.
在氧化亚氮（N₂O）排出过程中，动脉血氧分压（PaO₂）会因通常所称的弥散性缺氧现象而降低。作者质疑在氙气排出过程中是否会出现类似效应。
19只麻醉并麻痹的猪被随机使用含30%氧气与70% N₂O或氙气的吸入气体混合物进行机械通气30分钟。吸入气体被70%氮气和30%氧气的混合物取代。使用留置动脉传感器持续记录PaO₂和二氧化碳分压。
在N₂O排出期间，PaO₂从119±10毫米汞柱降至102±12毫米汞柱（均值±标准差）（P<0.01），在氙气排出期间从116±9毫米汞柱降至110±8毫米汞柱（P<0.01），基线与最低PaO₂值之间存在显著差异（P<0.01）（N₂O排出期间ΔPaO₂为17±6毫米汞柱，氙气排出期间为6±3毫米汞柱）。在N₂O排出期间PaCO₂值也降低（从39.3±6.3毫米汞柱降至37.6±5.8毫米汞柱）（P<0.01），在氙气排出期间（从35.4±1.6毫米汞柱降至34.9±1.6毫米汞柱；P<0.01）。N₂O组的ΔPaCO₂为1.7±0.9毫米汞柱，氙气组为0.5±0.3毫米汞柱（P<0.01）。
氙气麻醉苏醒期间不太可能发生弥散性缺氧，可能是因为该气体的血液溶解度低。
