Richardson B, Patrick J, Homan J, Carmichael L, Brien J
Research Institute, St. Joseph's Hospital, London, Ontario, Canada.
Am J Obstet Gynecol. 1987 Dec;157(6):1496-502. doi: 10.1016/s0002-9378(87)80250-8.
Cerebral oxidative metabolism and cotylendonary blood flow were measured in 10 unanesthetized fetal sheep (127 to 132 days' gestation) during a control period, after the first, third, and fourth infusions of four doses of 0.5 gm of ethanol per kilogram of maternal body weight infused into the ewe during 5 hours, and 24 hours after ethanol infusion. Preductal arterial and sagittal vein blood samples were analyzed for oxygen content, blood gases, pH, and ethanol. Cerebral and cotylendonary blood flow were measured with a radioactive microsphere technique. Fetal blood gases and pH changed little with the ethanol infusions, although PaO2 and oxygen content decreased 24 hours after ethanol infusion. Cotylendonary blood flow, which was decreased after the third and fourth ethanol infusions, did not account for these delayed hypoxemic changes. Similarly, cerebral oxidative metabolism was decreased when measured after each of the ethanol infusions, with no dose response or tolerance evident. This noted fall in fetal cerebral oxidative metabolism appears to be a direct depressant effect that was maximal at rather low fetal ethanol levels, which, if prolonged, might well affect cerebral growth and development. Recovery of cerebral metabolic function appeared complete by 24 hours. However, relative fetal hypoxemia was evident at this time, the mechanism of which remains to be determined.
在10只未麻醉的胎羊（妊娠127至132天）中，于对照期、在母羊5小时内每千克体重输注4剂0.5克乙醇的首次、第三次和第四次输注后以及乙醇输注24小时后，测量了脑氧化代谢和绒毛膜血流。分析了导管前动脉和矢状静脉血样中的氧含量、血气、pH值和乙醇含量。采用放射性微球技术测量脑和绒毛膜血流。尽管乙醇输注24小时后动脉血氧分压（PaO2）和氧含量降低，但胎羊血气和pH值随乙醇输注变化不大。第三次和第四次乙醇输注后绒毛膜血流减少，但这并不能解释这些延迟的低氧血症变化。同样，每次乙醇输注后测量时脑氧化代谢均降低，未显示出剂量反应或耐受性。所观察到的胎羊脑氧化代谢下降似乎是一种直接抑制作用，在相当低的胎羊乙醇水平时最大，如果持续下去，很可能影响脑的生长和发育。脑代谢功能在24小时时似乎完全恢复。然而，此时胎羊相对低氧血症明显，其机制尚待确定。
