C. Guilleminault et al., UPPER AIRWAY-RESISTANCE IN INFANTS AT RISK FOR SUDDEN-INFANT-DEATH-SYNDROME, The Journal of pediatrics, 122(6), 1993, pp. 881-886
To investigate the relationship between sudden infant death syndrome a
nd upper-airway-obstruction, we studied 14 term infants at a mean age
of 11 weeks who hod been identified as being at risk for sudden infant
death syndrome on the basis of clinical and family histories and poly
graphic monitoring. Respiratory efforts during sleep were investigated
by esophageal pressure monitoring (all 14 infants) and by monitoring
of flow with a pneumotachometer (6 infants). During apparently normol
sleep, increased respiratory efforts were shown by intermittent increa
ses in the magnitude of the negativity of esophageal pressure. Mild ch
anges in tidal volume occurred occasionally, always at the lowest moni
tored esophageal pressure of a breath sequence. These tidal volume dec
reases had no impact on oxygen saturation but led to o short arousal a
nd decreased respiratory efforts, followed by a return to normal breat
hing. Occasionally the abnormal increase in upper airway resistance di
d not lead to an immediate arousal but instead to a short obstructive
apnea that was then followed by an arousal. This investigation indicat
es the importance of arousal mechanisms in maintaining normal breathin
g during sleep. Any disruption of the arousal mechanisms during sleep
(including sleep fragmentation caused by repetitive arousals) may plac
e these infants with increased upper airway resistance at risk for obs
tructive apnea during sleep.