Department of Biomedical Engineering, Fondazione S. Maugeri - IRCCS, Montescano, Italy.
J Sleep Res. 2014 Jun;23(3):347-57. doi: 10.1111/jsr.12109. Epub 2013 Nov 29.
Fluctuations in sleep-wake state are thought to contribute to the respiratory instability of Cheyne-Stokes respiration in patients with heart failure by promoting the rhythmic occurrence of central apnea and ventilatory overshoot. There are no data, however, on the relationship between vigilance state and respiratory events. In this study we used a novel method to detect the occurrence of state transitions (time resolution: 0.25 s, minimum duration of state changes: 2 s) and to assess their time relationship with apnoeic events. We also evaluated whether end-apnoeic arousals are associated with a ventilatory overshoot. A polysomnographic, daytime laboratory recording (25 min) was performed during Cheyne-Stokes respiration in 16 patients with heart failure. Automatic state classification included wakefulness and non-rapid eye movement sleep stages 1-2. As a rule, wakefulness occurred during hyperpnoeic phases, and non-rapid eye movement sleep occurred during apnoeic events. Ninety-two percent of the observed central apneas (N = 272) were associated with a concurrent wakefulness → non-rapid eye movement sleep → wakefulness transition. The delay between wakefulness → non-rapid eye movement sleep transitions and apnea onset was -0.3 [-3.1, 3.0] s [median (lower quartile, upper quartile); P = 0.99 testing the null hypothesis: median delay = 0], and the delay between non-rapid eye movement sleep → wakefulness transitions and apnea termination was 0.2 [-0.5, 1.2] s (P = 0.7). A positive/negative delay indicates that the state transition occurred before/after the onset or termination of apnea. Non-rapid eye movement sleep → wakefulness transitions synchronous with apnea termination were associated with a threefold increase in tidal volume and a twofold increase in ventilation (all P < 0.001), indicating ventilatory overshoot. These findings highlight that wakefulness → non-rapid eye movement sleep → wakefulness transitions parallel apnoeic events during Cheyne-Stokes respiration in patients with heart failure. The relationships between state changes and respiratory events are consistent with the notion that state fluctuations promote ventilatory instability.
睡眠-觉醒状态的波动被认为通过促进中枢性呼吸暂停的节律性发生和通气过度来导致心力衰竭患者的 Cheyne-Stokes 呼吸的呼吸不稳定。然而，关于警觉状态与呼吸事件之间的关系尚无数据。在这项研究中，我们使用了一种新的方法来检测状态转变的发生（时间分辨率：0.25s，状态变化的最小持续时间：2s），并评估它们与呼吸暂停事件的时间关系。我们还评估了终末呼吸暂停唤醒是否与通气过度有关。在心力衰竭患者的 Cheyne-Stokes 呼吸期间进行了一项多导睡眠图、日间实验室记录（25min）。自动状态分类包括觉醒和非快速眼动睡眠阶段 1-2。通常，觉醒发生在过度通气阶段，而非快速眼动睡眠发生在呼吸暂停事件中。观察到的 92%的中枢性呼吸暂停（N=272）与同时发生的觉醒→非快速眼动睡眠→觉醒转变有关。在觉醒→非快速眼动睡眠转变和呼吸暂停开始之间的延迟为-0.3[-3.1，3.0]s[中位数（下四分位数，上四分位数）；P=0.99 检验零假设：中位数延迟=0]，在非快速眼动睡眠→觉醒转变和呼吸暂停终止之间的延迟为 0.2[-0.5，1.2]s（P=0.7）。正/负延迟表示状态转变发生在呼吸暂停开始/终止之前/之后。与呼吸暂停终止同步的非快速眼动睡眠→觉醒转变与潮气量增加三倍和通气增加两倍有关（均 P<0.001），表明通气过度。这些发现强调了在心力衰竭患者的 Cheyne-Stokes 呼吸期间，觉醒→非快速眼动睡眠→觉醒转变与呼吸暂停事件平行。状态变化与呼吸事件之间的关系与状态波动促进通气不稳定的观点一致。
