Lévy P, Pépin J L, Ferretti G
Service de pneumologie, CHRU de Grenoble, France.
Neurophysiol Clin. 1994 Jun;24(3):227-48. doi: 10.1016/s0987-7053(05)80187-x.
Obstructive sleep apnea results from a pharyngeal collapse. Upper airway can be investigated using either static or dynamic methods during wakefulness or when the patient is sleeping. Somnofluoroscopy is one of the dynamic methods allowing a visualization of the upper airway during sleep. A lateral projection of the pharynx is obtained during fluoroscopic examination which allows visualization of the upper airway dimensions and the bone structures (hyoid bone, cervical spine, mandible). Standard polygraphic parameters (EEG, EOG, flow rate, thoracic and abdominal movements) and fluoroscopic image are simultaneously acquired on the same videotape. Using this technique, we have described the typical pattern of events occurring during an episode of apnea: 1-beginning of airway occlusion in the oropharynx with anterior or posterior hooking of the soft palate, 2-suction on the uvula downwards and complete occlusion of the oropharynx with further extension to the hypopharynx, 3-active movements of the cervical spine and hyoid bone as if the patient is choking, 4-overcoming of the occlusion usually accompanied by opening of the jaw and occurring either as a sudden event throughout the length of the pharyngeal airway or as a progressive reopening from the hypopharynx. In a recent study, we have investigated upper airway dynamics when a continuous positive pressure with one level (CPAP) or two levels of pressure (BiPAP) was applied. When using CPAP with pressure below the optimal pressure, uvula movements were the first changes we observed, preceding the pharyngeal collapse. Lowering the expiratory pressure alone lead to a significant reduction in pharyngeal dimensions starting at expiration and extending also to inspiration when the expiratory pressure is further reduced. Using BiPAP may lead to upper airway instability. The frequency and the variability of this phenomenon need further studies to be established.
阻塞性睡眠呼吸暂停是由咽部塌陷引起的。可以在清醒状态或患者睡眠时使用静态或动态方法对上气道进行检查。睡眠荧光透视检查是一种动态方法，可在睡眠期间对上气道进行可视化观察。在荧光透视检查过程中获得咽部的侧位投影，从而可以观察上气道尺寸和骨骼结构（舌骨、颈椎、下颌骨）。标准的多导睡眠图参数（脑电图、眼电图、流速、胸廓和腹部运动）和荧光透视图像同时采集在同一录像带上。使用这项技术，我们描述了呼吸暂停发作期间发生的典型事件模式：1-口咽部气道阻塞开始，软腭向前或向后钩挂；2-悬雍垂向下抽吸，口咽部完全阻塞，并进一步延伸至下咽；3-颈椎和舌骨的主动运动，就好像患者在窒息；4-阻塞的克服通常伴随着下颌张开，并且要么是整个咽部气道突然发生，要么是从下咽逐渐重新开放。在最近的一项研究中，我们研究了应用单水平持续气道正压通气（CPAP）或双水平压力（BiPAP）时的上气道动力学。当使用低于最佳压力的CPAP时，我们观察到的第一个变化是悬雍垂运动，并先于咽部塌陷。仅降低呼气压力会导致咽部尺寸从呼气开始显著减小，当呼气压力进一步降低时，吸气时也会减小。使用BiPAP可能会导致上气道不稳定。这种现象的频率和变异性需要进一步研究来确定。
