Some factors modifying airway defensive reflexes

本研究的第一个目的是阐明持续刺激人的呼吸道黏膜所引起的呼吸道防御反射的模式，第二个目的是了解影响呼吸道反射的各种因素在调节呼吸道防御反射反应中的重要性。在这项研究中，我们建立了人类呼吸道防御反射的激发和评估的方法学。我们还研究了静脉麻醉剂(异丙酚)和麻醉剂(芬太尼)对呼吸道防御反射的影响。此外，还研究了吸烟习惯和七氟醚对呼吸道防御反射的影响。结果如下：1.喉部和气管刺激均可引起保护性反应，如咳嗽反射、呼气反射、2.麻醉深度的增加缩短了反应持续时间，但不影响反应的性质。3.单用异丙酚不可能抑制气道防御反射，但加用少量芬太尼可有效地抑制气道防御反射。4.吸烟习惯增强了气道反射，但只有机械刺激呼吸道粘膜时才明显。5.七氟醚对呼吸道刺激非常轻微，可能通过刺激鼻黏膜而引起气道防御反应。

The first purpose of this study is to elucidate patterns of airway defensive reflexes elicited by a constant stimulation of airway mucosa in humans and the second purpose is to see the importance of various factors influencing airway reflexes in modification of airway defensive reflex responses. In this study we established the methidoiogy of elicitation and eveluation of airway defensive reflexes in humans. We also investigated the effects of an intravenous anesthetic agent (propofol) and a narcotic (fentanyl) on airway defensive reflexes. In addition, the effects of smoking habit and the influence of a voltile agent (sevoflurane) on airway defensive reflexes were investigated. The results were summarized as follows :1.Both laryngeal and tracheal stimulation caused protective responses, such as cough reflex, expiration reflex, and spasmodic panting whereas bronchial stimulation caused little or no such responses.2.An increase in depth of anesthesia shortened the response duration but did not affect the nature of the elicited responses.3.It was impossible to suppress the airway defensive reflexes by administration of propofol alone but an addition of a small amount of fentanyl effectively depressed the airway defensive reflexes.4.Smoking habit augmented the airway reflex responses but this was evident only with mechanical stimulation of the airway mucosa.5.Sevoflurane which possesses a very mild airway-irritation may elicit airway defensive responses through the stimulation of the nasal mucosa.