Relationship between REM density, duty cycle, and obstructive sleep apnea in children.

Study Objectives: The pattern and distribution of rapid eye movement (REM) sleep changes during development, yet there have been few studies of REM density in children. Although children with obstructive apnea syndrome (OSAS) obstruct primarily during REM sleep, the relationship between REM density and obstructive apnea has not been established for this population. We hypothesized that (i) REM density and REM cycle duration increases over the course of the night in children, (ii) the duty cycle (inspiratory time divided by respiratory cycle time) increases over the course of the night in children with suspected OSAS, and (iii) the increase in REM density over the course of the night is associated with increased severity of obstructive apnea.

Upper airway dynamic responses in children with the obstructive sleep apnea syndrome.

Normal children have a smaller upper airway than adults, but, nevertheless, snore less and have less apnea. We have previously shown that normal children have an upper airway that is resistant to collapse during sleep. We hypothesized that this resistance to collapse is due to preservation of upper airway neuromotor responses during sleep.

Reliability of scoring arousals in normal children and children with obstructive sleep apnea syndrome.

Study Objectives: Scoring of arousals in children is based on an extension of adult criteria, as defined by the American Sleep Disorders Association (ASDA). By this, a minimum duration of 3 seconds is required. A few recent studies utilized modified criteria for the study of children, with durations as short as 1 second.

Developmental changes in upper airway dynamics.

Normal children have a less collapsible upper airway in response to subatmospheric pressure administration (P(NEG)) during sleep than normal adults do, and this upper airway response appears to be modulated by the central ventilatory drive. Children have a greater ventilatory drive than adults. We, therefore, hypothesized that children have increased neuromotor activation of their pharyngeal airway during sleep compared with adults.

Night-to-night variability of polysomnography in children with suspected obstructive sleep apnea.

Objectives: To determine whether a single polysomnographic night was a valid measure of obstructive sleep apnea syndrome (OSAS) in children with symptoms of sleep-disordered breathing.

Study Design: The night-to-night variability of respiratory and sleep parameters was measured prospectively in 30 snoring children aged 1.6 to 11.