Sleep Disorders 167the sleep phase is only two or three hours delayed, it is possible to let
the adolescent sleep in for a few days and then move wake-up time about
15 minutes earlier per day – bedtime will naturally move earlier too. When
sleep phase is delayed by three or four hours or more, it is usually better to
push it even later, with the adolescent staying awake an extra two or three
hours each night until the normal phase is re-established, for example,
moving forward 18 hours over a week instead of trying to move backwards
six hours. The shift is aided by bright lights while awake and darkness
while asleep. High levels of parental input and motivation are essential.
Obstructive sleep apnoea
Muscle tone in the upper airways decreases during sleep, so if the airways
are already partly blocked, sleep can lead to under-ventilation. Whereas
most adults with this condition are obese, the same only applies to
about 20% of affected children. The commonest cause in childhood is
enlargement of tonsils and adenoids. Children with Down syndrome are
also at high risk.
There is chronic loud snoring and parents may notice cyclical ob-
struction, involving repeated episodes when the child stops breathing or
struggles for breath. The child may wake up distressed after obstructive
episodes, or there may be frequent brief arousals that disrupt sleep quality
without parents noticing. Even when the child sleeps a normal number
of hours, the poor quality of sleep can lead to daytime sleepiness (or
hyperactivity, poor concentration, impulsiveness and irritability). Treat-
ment options include surgical removal of enlarged tonsils and adenoids, or
weight loss if obese. Tricyclic medication is sometimes used for adults with
obstructive sleep apnoea, but does not appear to be effective for children.
Night terrors, sleepwalking and confusional arousals
These all involve partial arousal (without waking) out of deep non-REM
sleep (see Box 20.1). They are therefore most likely to occur in the
first couple of hours of sleep when deep non-REM is concentrated (see
Box 20.1). They may occur more commonly when the child or adolescent
is living with anxiety, for example, after a break-in to the house.
Confusional arousalsare common among infants and toddlers: the child
cries, calls out or thrashes around, and does not respond when talked to.
If left alone, the child calms down and resumes peaceful sleep after about
5–15 minutes. Trying to wake the child generally increases agitation and
prolongs the episode.
Sleepwalkingoccurs in up to 17% of children, with 4–8 years being
the peak age. For up to ten minutes or so, the child wanders around
with eyes wide open and a glassy stare, and may then return to bed
or sleep elsewhere. Urination may occur in inappropriate places. There
is a significant risk of injury, for example, falling down stairs. The
environment needs to be made as safe as possible. Trying to restrain
or wake the child generally make things worse.