Chesson A L, Anderson W M, Walls R C, Bairnsfather L E
Department of Neurology, Louisiana State University, Shreveport.
Am Rev Respir Dis. 1993 Dec;148(6 Pt 1):1592-8. doi: 10.1164/ajrccm/148.6_Pt_1.1592.
A method of recording cumulative nocturnal oxygen desaturation was utilized to develop a quantitative index of nocturnal hypoxemia (SIT index) to provide reference values and distributional properties for apneic and nonapneic sleep-disordered patients. The SIT indices were compared in patients with varying degrees of obstructive sleep apnea (OSA) as determined by traditional methods of counting apneas and hypopneas. We studied 298 patients who were divided into five groups based on the presence and frequency of apnea or sleep-related respiratory deterioration. SIT indices for patient groups and individual patients were compared with the respiratory disturbance index (apneas + hypopneas x 60/total sleep time = RDI) using scatter plots, Kruskal-Wallis analysis of variance, and Mann-Whitney U tests. The OSA and non-respiratory-impaired patient groups had mean SIT values that were significantly different (p < 0.05). Subjects with severe apnea differed (p < 0.05) from subjects with mild and moderate apnea at SIT index thresholds < baseline, < 90, < 80, and < 70% SaO2, but subjects with mild and moderate apnea did not differ statistically from each other at any threshold. In individual patients with similar RDI values, considerable variation in SIT index can be seen, and the reverse is also true. This suggests that using both RDI and SIT may provide complementary information in assessing the severity of OSA.
一种记录夜间累积氧饱和度下降的方法被用于开发一种夜间低氧血症的定量指标（SIT指数），以提供呼吸暂停和非呼吸暂停睡眠障碍患者的参考值和分布特性。通过传统的呼吸暂停和低通气计数方法确定不同程度阻塞性睡眠呼吸暂停（OSA）的患者，对其SIT指数进行比较。我们研究了298名患者，根据呼吸暂停或睡眠相关呼吸恶化的存在和频率将其分为五组。使用散点图、Kruskal-Wallis方差分析和Mann-Whitney U检验，将患者组和个体患者的SIT指数与呼吸紊乱指数（呼吸暂停 + 低通气×60/总睡眠时间 = RDI）进行比较。OSA组和无呼吸功能损害的患者组的平均SIT值有显著差异（p < 0.05）。在SIT指数阈值 < 基线、< 90%、< 80%和 < 70% SaO2时，重度呼吸暂停患者与轻度和中度呼吸暂停患者存在差异（p < 0.05），但在任何阈值下，轻度和中度呼吸暂停患者之间无统计学差异。在RDI值相似的个体患者中，可以看到SIT指数有相当大的差异，反之亦然。这表明使用RDI和SIT在评估OSA严重程度时可能提供互补信息。
