Galland B C, Reeves G, Taylor B J, Bolton D P
Department of Paediatrics and Child Health, Otago Medical School, Dunedin, New Zealand.
Arch Dis Child Fetal Neonatal Ed. 1998 May;78(3):F189-94. doi: 10.1136/fn.78.3.f189.
To investigate and compare heart rate variability (HRV) and responses of heart rate and arousal to head-up tilting in infants sleeping prone and supine.
Thirty seven healthy infants aged 2-4 months were studied. HRV was measured for 500 beats while they were in a horizontal position. Subjects were then tilted 60 degrees head-up, and heart rate recorded over 1 minute and arousal responses observed. Data were collected during both quiet and active sleep for both prone and supine sleep positions.
HRV, as assessed by the point dispersion of Poincaré plots, was significantly reduced in the prone position for both sleep states. Sleep position did not influence the changes in heart rate seen during a head-up tilt. Full awakening to the tilt was common in active sleep but significantly less so in the prone position (15% of prone tests vs 54% supine). Full awakening to the tilt rarely occurred during quiet sleep in either sleep position.
This study provides some evidence that blunted arousal responses and/or altered autonomic function are a feature of the prone sleeping position. Decreased HRV may be a sign of autonomic impairment. It is seen in many disease states and in infants who later die of sudden infant death syndrome (SIDS).
研究并比较俯卧位和仰卧位睡眠的婴儿的心率变异性（HRV）以及心率和觉醒对抬头倾斜的反应。
对37名2至4个月大的健康婴儿进行研究。在他们处于水平位置时测量500次心跳的HRV。然后将受试者头部向上倾斜60度，记录1分钟内心率并观察觉醒反应。在安静睡眠和活跃睡眠期间，分别收集俯卧位和仰卧位睡眠姿势的数据。
通过庞加莱图的点离散度评估，两种睡眠状态下俯卧位的HRV均显著降低。睡眠姿势不影响抬头倾斜期间的心率变化。在活跃睡眠中，对倾斜完全觉醒很常见，但在俯卧位时明显较少（俯卧测试的15% 对仰卧的54%）。在任何一种睡眠姿势的安静睡眠期间，对倾斜完全觉醒很少发生。
本研究提供了一些证据，表明觉醒反应迟钝和/或自主神经功能改变是俯卧睡眠姿势的一个特征。HRV降低可能是自主神经功能受损的迹象。这在许多疾病状态以及后来死于婴儿猝死综合征（SIDS）的婴儿中都可见到。
