睡眠呼吸暂停综合征患者持续气道正压通气治疗前后微觉醒的变化及意义

目的探讨微觉醒的发生机制、临床意义及其在睡眠呼吸障碍性疾患诊断治疗中的应用价值。方法270例打鼾者均按国际标准方法进行多导睡眠呼吸监测（PSG），据此计算睡眠呼吸暂停低通气指数(AHI)、睡眠潜伏期(SL)、每小时氧减饱和度4%以上的次数(ODI4)及每小时微觉醒的次数(MAI)。其中28例患者应用持续气道正压通气(CPAP)同时复查PSG，在治疗前后均填写Epworth睡眠问卷(ESS)以评价患者嗜睡的改善程度。结果270例鼾症患者中，247例符合睡眠呼吸暂停低通气综合征(SAHS)的诊断，其AHI、ODI4、MAI及SL平均值分别为(43±27)次/h，(44±23)次/h，(29±16)次/h，(12±17)分。AHI与MAI，ODI4与MAI均呈正相关(r均为0.38，P均<0.001)。MAI与SL显著负相关(r=-0.15，P=0.02)，AHI与SL、ODI4与SL均无相关性(r分别为-0.09，-0.02，P均>0.1)。经CPAP治疗，28例患者的呼吸暂停基本消失，ODI4由(48±25)次/h降至(4±9)次/h，MAI由(27±18)次/h减至(15±9)次/h，主观(ESS)及客观(SL)评价均显示白天嗜睡改善。结论应用专门的计算机软件辅助分析SAHS患者睡眠状态下的脑电变化，可以判读最短持续时间达3秒的微觉醒。MAI可以作为白天嗜睡的重要指标，在SAHS诊断和CPAP疗效判断方面与AHI具有互补性。

Changes of microarousal in OSAS patients during CPAP

OBJECTIVE: To study the mechanism of microarousal, its clinical meaning and value in the diagnosis and treatment of sleep apnea-hypopnea syndrome (SAHS). METHODS: 270 snorers (218 men, 58 women) mean aged 48 years underwent standard polysomnography (PSG), from which AHI, sleep latency (SL), number of oxygen desaturation >/= 4% per hour (ODI(4)) and microarousal index (MAI) were calculated. The overnight PSG recordings were also repeated during nCPAP in 28 patients, who have filled in the Epworth Sleep Score (ESS) before and after the treatment to evaluate the improvement of daytime sleepiness. RESULTS: Of the 270 snorers, there were 247 SAHS patients.Their AHI, ODI(4), MAI and SL were (43 +/- 27)/h, (44 +/- 23)/h, (29 +/- 16)/h and (12 +/- 17) min, respectively. AHI and MAI, ODI(4) and MAI were both positively correlated (r = 0.38, both P < 0.001). MAI and SL were negatively correlated (r = -0.15, P = 0.02), while AHI and SL, ODI(4) and SL were not correlated (r = -0.09, -0.02, P > 0.1). Of the 28 patients after CPAP, ODI(4) decreased from (48 +/- 25)/h to (4 +/- 9)/h, MAI decreased from (27 +/- 18)/h to (15 +/- 9)/h. The ESS and SL indicated that subjective and objective sleepiness improved. CONCLUSIONS: Microarousals with at least 3 seconds EEG changes can be scored by computerized EEG analysis. MAI can reflect the severity of daytime sleepiness. MAI is complementary to AHI in the diagnosis and treatment of SAHS. After nCPAP, the patients' MAIs decreased and daytime sleepiness improved.