TOTAL INTRAVENOUS ANESTHES IA FOR ORAL AND MAXILLOFACIAL SURGERY - A COMPARI SON BETWEEN NORMOTENSIVE AND HYPERTENSIVE SUBJECTS

在兔，电刺激精神神经后，收缩压(SBP)表现为双相(降压后升压)反应。降压反应，称为三叉神经降压反应，在低频刺激后显著。芬太尼抑制升压反应，可乐定、新斯的明和L苯异丙基腺苷抑制升压反应。在相同时间，可乐定和L-苯异丙基腺苷均能剂量依赖性地降低血压。相反，电刺激大鼠的脑神经后，SBP主要表现为升压反应。尽管芬太尼对SBP无影响，但可乐定在兔实验中可抑制升压反应，并呈剂量依赖性降低SBP。电刺激精神神经30秒以上可产生持续的SBP升高。芬太尼和可乐定可调节这些SBP反应。这些结果表明，在不同的伤害性机制部位，这些药物的适当组合可能会导致安全有效的口腔颌面外科全静脉麻醉。

In rabbits, systolic blood pressure (SBP) showedbiphagic (depressor followedby presjsor) responses following electrical stimulation of the mental nerve. Depressor response, known as the trigeminal depressor response, wasprominent after low frequency stimulations. Fentanyl inhibited depressor response, whereas clonidine, neostigmine and L-phenylisopropyladenosine inhibited pressor response. At t|ie sane time, clonidine and L-phenylisopropyladenosine produced a dose-dependent SBP reduction. In contrast, SBP mainly showed pressor responses following electrical stimulation of the mentalnerve in rats. Although fentanyl revealed no effects on SBP change, clonidine, as in the rabbit experiments, inhibited pressor response along witha dose-dependent SBP reduction.Electrical stimulation of the mental nerve for more than 30 sec produced sustained SBP elevation.Fentanyl and clonidine may modulate these SBP responses.These results suggest that appropriate combinations of these agents that act at different siteof the nociceptive mechanisms may result in safe and effective total intravenous anesthesi for oral and maxillofacial surgery.