Basic research for preventing pulmonary aspiration during intravenous sedation

静脉镇静在口腔外科的一般管理中被广泛使用。这种技术最常见的并发症之一是肺吸入。咳嗽反射是一种气道保护性反射，可防止肺吸入。目前还不清楚反射通路的哪一部分受到静脉麻醉剂的影响。本研究旨在探讨GABA能对口面区血管扩张副交感神经反射的调节作用。口面区血管扩张副交感神经反射与咳嗽反射具有相似的反射途径。微量注射GABA、GABA_A受体激动剂或GABA_B受体激动剂均能显著抑制下唇的副交感神经反射性血管舒张反应，而这一反应可被各受体拮抗剂所阻断。

Intravenous sedation is widely used during the general management of oral surgery. One of the most common complications of this technique is the pulmonary aspiration. Cough reflex is an airway protective reflex that prevents the pulmonary aspiration. It has been unclear which part of the reflex pathway is affected by the intravenous anesthetics. In the present study, we evaluated the GABAergic modulation on the parasympathetic reflex vasodilatation in orofacial area, which has the similar reflex pathway to cough reflex. Microinjection of either GABA, GABA_A receptor agonist, or GABA_B receptor agonist significantly inhibited the parasympathetic reflex vasodilatation in the lower lip, which were blocked by each receptor antagonists.