Effects of nitrous oxide on cerebral metabolic rate in rats anaesthetized with isoflurane.
Effects of nitrous oxide on cerebral metabolic rate in rats anaesthetized with isoflurane.
复制标题
一氧化二氮对异氟烷麻醉大鼠脑代谢率的影响。
DOI：
10.1093/bja/65.2.210
复制
发表时间：
1990
影响因子：
9.8
通讯作者：
McAllister,A
中科院分区：
文献类型：
--
作者：
Reasoner,DK;Warner,DS;Todd,MM;McAllister,A
在一些物种中已经证明，当在挥发性麻醉剂中加入一氧化二氮时，脑血流量（CBF）会显著增加。这种血流反应可能是由于脑代谢率的增加或氧化亚氮对脑血管的直接作用造成的。为了研究这一点，在接受异氟醚麻醉或不接受氧化亚氮麻醉的大鼠中，用放射自显像法测定了脑葡萄糖代谢率（CMRglu）。异氟醚麻醉深度从0.5增加到1.0 MAC， CMRglu显著降低(52 （SD11) μmol/100 gmin - 1vs 39 (8) μmol/100 gmin - 1）。相比之下，添加70%氧化亚氮（0.5 MAC）到0.5 MAC异氟醚麻醉（1 MAC）后，CMRglu保持不变（54 (4)μmol/100 g min−1）。我们得出结论，当给予0.5 MAC异氟醚时，70%氧化亚氮不会改变脑代谢率。由于CBF在非常相似的条件下显著增加，我们的数据表明，当与挥发性剂一起施用时，氧化亚氮对CBF的影响是直接的，并由脑代谢率变化以外的因素介导。
It has been demonstrated in several species that a significant increase in cerebral blood flow (CBF) occurs when nitrous oxide is added to a volatile anaesthetic. This blood flow response could result from an increase in cerebral metabolic rate or from a direct effect of nitrous oxide on cerebral vessels. To investigate this, the cerebral metabolic rate for glucose (CMRglu) was determined autoradiographically in rats receiving isoflurane anaesthesia with or without nitrous oxide. An increase in anaesthetic depth from 0.5 to 1.0 MAC achieved with isoflurane alone caused a significant reduction in CMRglu (52 (SD11) μmol/100 gmin−1vs 39 (8) μmol/100 g min−1). In contrast, the addition of 70% nitrous oxide (0.5 MAC) to 0.5 MAC isoflurane anaesthesia (1 MAC total) left CMRglu unchanged (54 (4) μmol/100 g min−1). We conclude that 70% nitrous oxide does not alter cerebral metabolic rate when administered with 0.5 MAC isoflurane. Because CBF increases substantially under very similar conditions, our data indicate that the CBF effects of nitrous oxide, when administered with a volatile agent, were direct and mediated by factors other than changes in cerebral metabolic rate.