Lijowska A S, Reed N W, Chiodini B A, Thach B T
The Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
J Appl Physiol (1985). 1997 Jul;83(1):219-28. doi: 10.1152/jappl.1997.83.1.219.
Infants are prone to accidental asphyxiation. Therefore, we studied airway-defensive behaviors and their relationship to spontaneous arousal behavior in 41 healthy sleeping infants (2-26 wk old), using two protocols: 1) infant was rebreathing expired air, face covered by bedding material; and 2) infant was exposed to hypercarbia, face uncovered. Multiple measurements of respiratory and motor activities were recorded (video, polygraph). The infants' response to increasing hypercarbia consisted of four highly stereotyped behaviors: sighs (augmented breaths), startles, thrashing limb movements, and full arousal (eyes open, cry). These behaviors occurred abruptly in self-limited clusters of activity and always in the same sequence: first a sigh coupled with a startle, then thrashing, then full arousal. Incomplete sequences (initial behaviors only) occurred far more frequently than the complete sequence and were variably effective in removing the bedding covering the airway. In both protocols, as inspired CO2 increased, incomplete arousal sequences recurred periodically and with increasing frequency and complexity until the infant either succeeded in clearing his/her airway or was completely aroused. Spontaneous arousal sequences, identical to those occurring during hypercarbia, occurred periodically during sleep. This observation suggests that the infant's airway-defensive responses to hypercarbia consist of an increase in the frequency and complexity of an endogenously regulated, periodically occurring sequence of arousal behaviors.
婴儿容易发生意外窒息。因此，我们采用两种方案研究了41名健康睡眠婴儿（2至26周龄）的气道防御行为及其与自发觉醒行为的关系：1）婴儿呼吸呼出的空气，面部被床上用品覆盖；2）婴儿暴露于高碳酸血症，面部未覆盖。记录了呼吸和运动活动的多次测量结果（视频、多导仪）。婴儿对逐渐增加的高碳酸血症的反应包括四种高度刻板的行为：叹息（增强呼吸）、惊跳、肢体剧烈运动和完全觉醒（眼睛睁开、哭泣）。这些行为以自我限制的活动簇突然出现，并且总是按相同顺序出现：首先是一声叹息并伴有惊跳，然后是剧烈运动，然后是完全觉醒。不完全序列（仅初始行为）出现的频率远高于完整序列，并且在清除覆盖气道的床上用品方面效果各异。在两种方案中，随着吸入二氧化碳的增加，不完全觉醒序列会周期性地反复出现，且频率和复杂性不断增加，直到婴儿成功清理气道或完全觉醒。与高碳酸血症期间出现的自发觉醒序列相同，在睡眠期间也会周期性出现。这一观察结果表明，婴儿对高碳酸血症的气道防御反应包括内源性调节的、周期性出现的觉醒行为序列的频率和复杂性增加。
