中文摘要：

目的评价阻塞性睡眠呼吸暂停低通气综合征（OSAHS）患者肌松时上气道平面塌陷的特点。方法接受悬雍垂腭咽成形术男性OSAHS患者30例，年龄20～59岁，BMI21～36kg／m2，ASA分级Ⅱ或Ⅲ级，呼吸暂停低通气指数28—102次／h。静脉注射咪达唑仑1mg和舒芬太尼5μg，慢诱导，完成经鼻气管内插管后静脉注射异丙酚0．5mg／kg和维库溴铵0．08mg／kg。靶控输注异丙酚和瑞芬太尼维持麻醉。完全肌松后使用连接图像工作站的纤维鼻咽喉镜，定标测量阻塞段长度和记录咽腔不同气道平面的塌陷情况。给予咽腔内正压（3—20cm H2O），逐步增加压力（每次增加1cm H2O），记录随压力升高不同气道平面的截面积和软腭后区的临界开放压力。结果完全肌松后，硬腭平面完全塌陷的1例（3％），软腭悬雍垂平面完全塌陷30例（100％），舌咽平面完全塌陷23例（77％）。1例患者硬腭平面阻塞；其余患者均为软腭后区气道阻塞，阻塞段长度16±9mm。咽腔内压力每增加1cmH2O，硬腭平面截面积增加（10±4）mm2，软腭悬雍垂平面截面积增加（28±18）mm2.临界开放压力范围3～18cm H2O，90％患者临界开放压力≤15cm H2O。结论软腭悬雍垂平面是OSAHS患者肌松时上气道最易塌陷的部分，90％患者的临界开放压力不超过15cm H2O。

英文摘要：

Objective To investigate the characteristics of upper airway collapse in patients with obstruc- tive sleep apnea-hypopnea syndrome （OSAHS） when muscle is fully relaxed.Methods Thirty male ASA Ⅱ or Ⅲ 2 patients with OSAHS aged 20-59 yr with body mass index 21-36 kg/m and apnea-hypopnea index （AHI） of 28-102 times/h were studied. The patients were sedated with iv midazolam 1 mg and sufentanil 5 μg. Nasotracheal intuba- tion was then performed under topical anesthesia with 1% dicaine. After confirmation of correct position of nasotra- cheal tube, anesthesia was induced with propofol 0.5 mg/kg and vecuronium 0.08 mg/kg and maintained with tar- get-controlled infusion of propofol and remifentanil. BIS was maintained at 40-60. Fiberopticnasopharyngoscope and pressure transducer were inserted via contralateral nasal cavity and connected with imaging workstation. The site and length of the obstruction were measured and calibrated. Positive pressure was applied to the pharyngeal cavity and gradually increased in increments of 1 cm H2O until 20 cm 1-12 O. The change in cross-section area and critical opening pressure at different planes in pharyngeal cavity were recorded.Results Complete obstruction occurred at the plane of hard palate in one patient （3%）. The soft palate and Uvula completely collapsed in all 30 patients （ 100 % ）. The collapse occurred at tongue level in 23 patients （77 % ）. Every 1 cm H20 increase in pressure pro- duced increase in cross-section area by （ 10 ± 4 ） mm2 at the level of hard palate and by（ 28 ± 18） mm2 at the lev- el of soft palate and uvula. The critical opening pressure ranged from 3 to 18 cm H2O and was ≤15 cm H2O in 90% patients. Conclusion Soft palate and uvula collapse in all patients with OSAHS when muscle is fully re- laxed. The critical opening pressure is ≤15 cm H20 in 90% patients.