Laryngocele and epiglottic cyst as rare causes of obstructive sleep apnea

Introduction  Upper airway pathologies have been reported to cause obstructive sleep apnea (OSA). Case report  We present two rare cases of OSA, one with laryngocele secondary to partial laryngectomy and the other with epiglottic cyst. Conclusion  In the management of cases with OSA symptoms, a detailed evaluation of upper airways, including endoscopic and radiological examinations as well as polysomnography, should be done.     

阻塞性睡眠呼吸暂停综合征与胰岛素抵抗相关性的荟萃分析

目的 通过荟萃分析总结阻塞性睡眠呼吸暂停综合征(obstructive sleep aponea syndrome,OSAS)和胰岛素抵抗(insulin resistance,IR)的相关性的循证医学证据.方法 检索中西文数据库,对入选文献做资料提取,并总结分析.结果 共有61篇文献入选,英文40篇,中文21篇.其中关于OSAS患者睡眠呼吸紊乱与糖尿病或IR相关性的流行病学调查或临床研究35项,25项研究认为OSAS严重程度与糖尿病或IR独立相关.此外,关于CPAP治疗是否能改善OSAS患者IR的临床研究共26篇,14项发现CPAP治疗后OSAS患者IR有所改善,但大部分研究未设对照组.结论 OSAS和IR之间存在独立相关性,CPAP治疗是否能改善OSAS患者IR有待大样本量的随机双盲对照研究来确认.     

急性脑血管病与睡眠呼吸障碍相关性的临床观察

和康复预后具有重要的意义.     

冠心病患者中睡眠呼吸暂停综合征的监测及其临床意义

目的:观察冠心病(CHD)患者中阻塞性睡眠呼吸暂停综合征(OSAS)的患病率,探讨OSAS与CHD的关系.方法:83例可疑CHD的患者行冠状动脉造影,依据造影结果分为CHD组(48例),冠状动脉造影阴性组(35例), 83例患者均行多导睡眠仪(PSG)监测,依据PSG监测得出的睡眠呼吸暂停低通气指数(AHI)分为轻度OSAS组(10≤AHI<20, 23例)、中重度OSAS组(AHI≥20,21例)和非OSAS组(对照组,AHI<10, 39例).3组均计算Gensini评分,用于评估冠状动脉粥样硬化病变的程度.用Logistic回归评估OSAS以及其他危险对CHD的影响.结果:CHD组中OSAS的患病率高于冠状动脉造影阴性组.轻度和中重度OSAS组,最低血氧饱和度低于对照组;CHD患病率高于对照组;冠状动脉病变单支受累百分率显著高于对照组,多支受累百分率高于对照组;中重度OSAS组的Gensini评分显著高于对照组.多因素Logistic回归得出OSAS、高血压以及脂蛋白(a)与CHD独立相关.结论:在冠状动脉造影证实的CHD患者中OSAS患病率较高,多因素回归发现OSAS与CHD独立相关,OSAS可能是导致冠心病的一个重要的独立危险因素.     

Motor unit recruitment in human genioglossus muscle in response to hypercapnia

Study Objectives:

Single motor unit recordings of the genioglossus (GG) muscle indicate that GG motor units have a variety of discharge patterns, including units that have higher discharge rates during inspiration (inspiratory phasic and inspiratory tonic), or expiration (expiratory phasic and expiratory tonic), or do not modify their rate with respiration (tonic). Previous studies have shown that an increase in GG muscle activity is a consequence of increased activity in inspiratory units. However, there are differences between studies as to whether this increase is primarily due to recruitment of new motor units (motor unit recruitment) or to increased discharge rate of already active units (rate coding). Sleep-wake state studies in humans have suggested the former, while hypercapnia experiments in rats have suggested the latter. In this study, we investigated the effect of hypercapnia on GG motor unit activity in humans during wakefulness.

Setting:

Sleep research laboratory.

Participants:

Sixteen healthy men.

Measurements and Results:

Each participant was administered at least 6 trials with P_etCO₂ being elevated 8.4 (SD = 1.96) mm Hg over 2 min following a 30-s baseline. Subjects were instrumented for GG EMG and respiratory measurements with 4 fine wire electrodes inserted subcutaneously into the muscle. One hundred forty-one motor units were identified during the baseline: 47% were inspiratory modulated, 29% expiratory modulated, and 24% showed no respiratory related modulation. Sixty-two new units were recruited during hypercapnia. The distribution of recruited units was significantly different from the baseline distribution, with 84% being inspiratory modulated (P < 0.001). Neither units active during baseline, nor new units recruited during hypercapnia, increased their discharge rate as P_etCO₂ increased (P > 0.05 for all comparisons).

Conclusions:

Increased GG muscle activity in humans occurs because of recruitment of previously inactive inspiratory modulated units.

Citation:

Nicholas CL; Bei B; Worsnop C; Malhotra A; Jordan AS; Saboisky JP; Chan JKM; Duckworth E; White DP; Trinder J. Motor unit recruitment in human genioglossus muscle in response to hypercapnia. SLEEP 2010;33(11):1529-1538.     

Deficits in involuntary attention switching in obstructive sleep apnea syndrome

Cognitive functions are altered in patients with obstructive sleep apnea syndrome (OSAS) and it has been proposed that vigilance and attentional deficits play a pivotal role in all aspects of these deficits. One way to assess attentional system integrity is the study of event-related-potentials (ERP), but only a few ERP studies have been conducted in patients with OSAS. The aim of the study was to use ERP to further assess attentional impairments in these patients. Thirteen OSAS patients and 13 age-matched controls underwent a night of polysomnographic recording. Each subject was also tested with an ERP paradigm where standard (95%, 1000Hz), high deviant (2.5%, 1250Hz) and low deviant (2.5%, 1050Hz) tones were presented. Subjects were asked to ignore the stimuli and read during the task. Mismatch negativity (MMN) and P3a amplitudes and latencies were measured. No between-group difference was observed for sleep stages, except a lower percentage of rapid eye movement (REM) sleep in patients with OSAS (p<0.01). Moreover, the OSAS group showed a higher micro-arousal index and more sleep transitions than the control group (p<0.05). A significant group effect was found for the amplitude of the P3a component (p<0.05) that was lower in patients with OSAS for both high and low deviant tones. No between-group difference was found for the MMN and the P3a latencies. In conclusion, patients with OSAS have specific alterations of the P3a component that reflects involuntary attention switching, but automatic auditory processing assessed by MMN appears to be preserved.