 Basic
Facts
- Prevalence - between 1 and 11%
- Simple snoring is more common than sleep apnea
and thought to be without any adverse effects.
- Majority of the children with snoring do not
have sleep apnea.
- African-Americans are more prone to this condition
when compared to Caucasians.
- Sleep disordered breathing in children includes:
- Obstructive sleep apnea (OSA)
- Upper airway resistance syndrome (UARS)
- Primary snoring
What is the cause?
Obstructive sleep apnea in children is usually due to swelling
of the tonsils and adenoids. The volume of this tissue in the
upper airway increases from around six months of age up to puberty,
with the maximum proliferation occurring in the preschool years.
This age coincides with the peak incidence of OSA in children.
Obesity as a cause of OSA is increasing in frequency, especially
in school age children.
Abnormal craniofacial developments such as Pierre Robin sequence,
Treacher Collin's, Apert's and Crouzon's syndromes and neuromuscular
abnormalities such as cerebral palsy and anoxic encephalopathy
have a much higher incidence of severe OSA. Children with allergies
are more likely to have habitual snoring. The swelling of the
nasal mucosa along with increased secretions causes airway obstruction
during sleep.
What happens in obstructive sleep apnea?
There is cyclical upper airway obstruction causing hypoxia (lowering
of oxygen saturation in blood) and hypercapnea (retention of
carbon dioxide). This usually occurs during deeper levels of
sleep and results in an arousal causing fragmentation and disruption
of normal sleep.
What
are the possible adverse effects of OSAS?
- Mouth breathing and hyponasal speech with articulatory
errors
- Decreased school performance in children.
- Hyperactivity, attention deficit, aggression
and other behavioral disorders
- Higher blood pressures
- Nocturnal enuresis (bedwetting)
- Failure to thrive due to a combination of poor
appetite, impaired growth hormone secretion and/or increased
work of breathing
Severe cases may progress to cardiopulmonary
dysfunction.
What tests are available and do they have to be done?
Sleep studies remain the gold standard for the diagnosis of
OSA in adults and children.
However, a good history and physical examination by a skilled
clinician can identify most cases of sleep apnea in children.
Sleep studies are generally used in very young children and when
in doubt about the diagnosis.
Overnight PSG can be performed at home or in
the sleep laboratory. Daytime "nap studies" and nighttime pulse
oximetry have fair positive predictive value, but cannot exclude
the presence of significant sleep apnea.
Audio and/or video recordings and their analyses may be able
to confirm severe sleep apnea but cannot differentiate mild OSA
from primary snoring. Soft tissue radiographs of the nasopharynx
have limited use in assessing adenoid enlargement when compared
to flexible endoscopy.
What values would be considered abnormal in a pediatric
sleep study?
- Apnea index of >1
- Oxygen desaturation of >4% more than three
times an hour or associated with a >25% change in heart
rate
- Oxygen desaturation <92%
- Elevation of end-tidal CO2 to >50mm/hg
for >8%
of total sleep time or 45mm/hg for >60% of sleep time
What
is the treatment? Medical
therapy with nasal steroids may help some, especially those
with allergies. Adenotonsillectomy remains the mainstay
of treatment for pediatric obstructive sleep apnea. Sometimes
an adenoidectomy alone or a tonsillectomy alone may help relieve
obstruction.
At
what age is it safe to perform these procedures?
No age is a contraindication for surgery if the conditions that
require it exist.
The usual age at which a tonsillectomy and adenoidectomy is
performed is between 4 and 7 years. Surgery in very young children
should preferably be performed in an institution that has facilities
for pediatric intensive care.
Should
children be monitored in hospital overnight after a tonsillectomy
for sleep apnea?
Most can go home if they meet hospital discharge
criteria. Very young children and those considered as being in
the high risk category (your doctor will tell you) are usually
observed overnight.
What are the common complications of this procedure?
- Airway obstruction due to swelling of the tissues
or excessive drowsiness
- Dehydration especially in young children
- Bleeding - early and delayed
- Change in voice
- Nasal regurgitation
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