Current Treatment for Childhood Obstructive Sleep Apnea Li-Ang Lee, Yu-Shu Huang,

Transcription

Current Treatment for Childhood Obstructive Sleep Apnea Li-Ang Lee, Yu-Shu Huang,
REVIEW ARTICLE
Current Treatment for Childhood Obstructive Sleep
Apnea
Li-Ang Lee,1,2 Yu-Shu Huang,1,3 Kin-Sun Wong,1,4 Cheng-Hui Lin,1,5 Ning-Hung Chen,1,6
Hsueh-Yu Li1,2
Sleep Center, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan
Division of Pediatric Otolaryngology, Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan
3
Division of Child Psychiatry, Department of Psychiatry, Chang Gung Memorial Hospital, Chang Gung University,
Taoyuan, Taiwan
4
Division of Pediatric Pulmonology, Department of Pediatrics and Internal Medicine, Chang Gung Memorial
Hospital, Chang Gung University, Taoyuan, Taiwan
5
Division of Craniofacial Surgery, Department of Plastic and Reconstructive Surgery, Chang Gung Memorial
Hospital, Chang Gung University, Taoyuan, Taiwan
6
Division of Thoracic Medicine, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung
University, Taoyuan, Taiwan
1
2
Abstract
About 5% of children are affected by obstructive sleep apnea (OSA) and it has been the
most common disorders encountered at sleep centers. Snoring, mouth breathing, labored
breathing, and witnessed apnea are the core symptoms and signs of OSA in children.
The true mechanism of childhood OSA remains elusive and is probably multifactorial.
Adenotonsillar hypertrophy, nasal obstruction, craniofacial anomaly, obesity, and
neuromuscular disorder are possible reasons. An overnight polysomnography confirms
the diagnosis of OSA when apnea-hypopnea index >1 episodes/h. OSA are associated
with inattention, hyperactivity, learning problem, elevated blood pressure, inadequate
somatic growth and nocturnal enuresis. Weight control, anti-inflammatory therapy,
nasal continuous positive airway pressure, oral appliance, rapid maxillary expansion,
supraglottoplasty, craniofacial reconstruction, and tracheostomy have been proven
effective for the treatment of pediatric OSA; however, adenotonsillectomy continues to
be the primary treatment of childhood OSA. Despite snoring and respiratory difficulty
are greatly reduced by adenotonsillectomy, residual disease is common. This evidencebased article provides a systemic review of the literature regarding indications, timing,
postoperative management, and complications of OSA therapy in children, and we
propose a clinical guideline on the treatment for childhood OSA at a tertiary sleep center.
(J Pediatr Resp Dis 2012;8:98-111)
Key words: obstructive sleep apnea, prevalence, polysomnography, treatment,
adenotonsillectomy.
INTRODUCTION
Childhood obstructive sleep apnea (OSA) is
a common disease characterized by intermittent
Correspondence: Hsueh-Yu Li, MD, FACS.
Address: Department of Otolaryngology, Chang Gung
Memorial Hospital, No. 5, Fu-Shin Street, Kweishan,
Taoyuan, Taiwan. Tel: 886-3-3281200 ext 3968. Fax:
886-3-3979361. E-mail: [email protected].
Received: October 26, 2012. Accepted: November 26,
2012.
snoring and respiratory disturbance during sleep. In
the past, most parents perceived that OSA as serious,
however only a small percentage (15%) of them
considered themselves to be “very knowledgeable”
or “knowledgeable”, particularly about symptoms,
consequences, and treatment.1 In one of our recent
unpublished studies, we performed an internet-based
survey (http://www.pollster.com.tw/; study period:
October 20, 2011-November 2, 2011; total 766
mothers with snoring sleep partners interviewed): 37%
Journal compilation © 2012 Taiwan Society of Pediatric Pulmonology
Lee LA, et al.
of mothers had at least one child who present with
snoring, and 21% of pediatric snorers had habitual
snoring. Unfortunately, about 90% of mothers with
snoring children did not consider snoring as a sign of
OSA and they were casually related with obesity. This
highlights the importance that sleep physicians need to
educate both clinicians and parents more proactively.
Primary snoring and OSA are the most common
manifestations of sleep-disordered breathing (SDB),
whereas upper airway resistance syndrome and
obstructive hypoventilation were unusual. The
epidemiology, symptoms and signs of OSA in children
are not well defined and they are different from the
adult population. According to a systematic review by
Marcus et al., an estimated population prevalence of
OSA was 1 to 5%.2 Moreover, OSA is more prevalent
among obesed boys than girls.
Nocturnal sleep study by polysomnography
(PSG) is the golden standard of diagnosis, and has
been recommended for all children with snoring.2
Notably, there are many co-existing predisposing
factors of OSA, such as adenotonsillar hypertrophy,
allergic rhinitis, obesity, craniofacial anomalies,
laryngomalacia, neuromuscular disease, and hereditary
genetic disorders.2-4 Moreover, intermittent hypopnea
and obstructive apnea impair ventilation during sleep,
while changes in sleep architecture and long-term upper
airway obstruction may lead to significant morbidities
such as systemic elevation of arterial blood pressure,
cardiovascular disease, metabolic morbidity, growth
failure, attention deficit/hyperactivity (ADHD), poor
learning, and nocturnal enuresis. More importantly,
these morbid complications will follow with longlasting consequences without timely diagnosis and
intervention, which can cause marked increases in
healthcare-related costs.
Pathophysiology
The definite pathophysiologic mechanism of
pediatric OSA is still not well understood. Obstructive
cycling, increased respiratory effort, flow limitation,
tachypnea, and/or gas exchange abnormalities resulting
variable abnormal respiratory effort and disturbance
of sleep homeostasis. Imbalance neuromuscular
activation, ventilatory control, and arousal threshold
99
cause the instability of the upper airway. Hypertrophy
of the tonsils and adenoid are frequently encountered
in childhood OSA, and adenotonsillectomy reduces
adverse respiratory events defined by PSG and
decrease risks of related morbidities.5 However,
residual morbidity after adenotonsillectomy indicates
that there were other factors need to be implicated for
OSA to develop. For example, obesity increases airflow
resistance and pharyngeal collapsibility, particularly
in obesed children.6 Craniofacial deformities increase
upper airway resistance which may be decreased by
craniofacial reconstruction..2-4 Accordingly, OSA is
the consequence of one or more disorders with comorbid diseases that mandate further evaluation and
management.
Diagnosis
Coexisting medical disorders are frequently present
in children with OSA.2-4 Accordingly, information
such as clinical indicators of childhood OSA, such
as symptoms, signs, anatomical and physiologic
characteristics, and family history (Table 1), and
underlying diseases and morbidities (Table 2) should
be obtained.
The most commonly applied tool to quantify the
symptoms and quality of life in childhood OSA is the
OSA-18 questionnaire.7 For the children with OSA,
this structured questionnaire, scored by parents or
caregivers, is valid, reliable, and easy-to-administer
for the evaluation of child’s quality of life at baseline
and after treatment.8 The items cover sleep disturbance,
physical suffering, emotional distress, daytime
problems, caregiver concerns and total quality of life
(Table 3). Each symptom frequency is rated from
‘none’’ to ‘‘all of the time’’ by a 7-point ordinal scale
and thereby, the OSA-18 survey score is between 18 and
126. The total scores less than 60 have been suggested
to be a small impact on OSA child’s quality of life,
scores between 60 and 80 suggest a moderate impact,
and scores above 80 suggest a large impact.7 Although
OSA-18 questionnaire has been originally designed for
measuring the quality of life, the “sleep disturbance”
subscale including loud snoring, witnessed apnea,
labored breathing, and restless sleep are important
clinical indictors for childhood OSA.8 For example,
Current treatment for childhood OSA
Table 1. Clinical indicators of childhood obstructive sleep apnea
Symptoms and signs
Anatomical and physiological characters
Snoring
Underweight or overweight
Witnessed apnea
Tonsillar hypertrophy
Labored breathing
Adenoidal hypertrophy
Restless sleep
Allergic rhinitis
Mouth breathing
Micrognathia/retrognathia
Impaired behavior
High-arched palate
Nasal blockage
Laryngomalacia
Sweating during sleep
Neuromuscular disorder,
Cyanosis
Prematurity
Daytime sleepiness
Failure to thrive
Family history
Hypertension
Obstructive sleep apnea
Table 2. Medical conditions associated with childhood obstructive sleep apnea
Underlying disease
Morbidities
Obesity
Cardiovascular disorder
Allergic rhinitis or asthma
Elevated systolic and diastolic blood pressure (> 95%),
pulmonary hypertension, cor pulmonale
Craniofacial problem
Growth problem
Mild abnormal structures
Inadequate somatic growth, failure to thrive
Neurocognitive problem
Small mandible ± mandibular malpositioning
Narrow nasomaxillary complex ± high and narrow
Attention deficit hyperactivity disorder, poor learning
hard palate
(decreasing cognitive and academic functions), mental
retardation
Urinary dysfunction
Marked midface (nasomaxillary) deficiency
Apert syndrome, Crouzon syndrome, Pfeiffer
Nocturnal enuresis
syndrome, repaired cleft palate
Metabolic syndrome
Marked mandibular hypoplasia
Pierre Robin sequence, severe juvenile rheumatoid
Insulin resistance, dyslipidemia
arthritis, Treacher Collins syndrome, Nager syndrome,
Stickler syndrome
Neuromuscular disorder
Ear problems
Cerebral palsy, Duchenne muscular dystrophy
Recurrent otitis media
Complex disease
Oral-motor dysfunction
Down
syndrome,
achondroplasia,
Prader-Willi
Phonological impairment
syndrome, Mucopolysaccharidoses
100
Lee LA, et al.
Table 3. Quality of life survey questionnaire for children with obstructive sleep apnea (OSA-18)7
hardly
a good
none of
a little of some of
most of
any of
bit of the
the time
the time
the time
the time
the time
time
Sleep Disturbance
During the past 4 weeks, how often has your child had…
…loud snoring?
1
2
3
4
5
6
…breath holding spells or pauses
1
2
3
4
5
6
in breathing at night?
…choking or gasping sounds while
1
2
3
4
5
6
asleep
…restless sleep or frequent
1
2
3
4
5
6
awakenings from sleep?
Physical symptoms
During the past 4 weeks, how often has your child had…
…mouth breathing because of
1
2
3
4
5
6
nasal obstruction?
…frequent colds or upper
1
2
3
4
5
6
respiratory infections?
…nasal discharge or runny nose?
1
2
3
4
5
6
…difficulty swallowing foods?
1
2
3
4
5
6
Emotional distress
During the past 4 weeks, how often has your child had…
…mood swings or temper
1
2
3
4
5
6
tantrums?
…aggressive or hyperactive
1
2
3
4
5
6
behavior?
…discipline problems?
1
2
3
4
5
6
Daytime function
During the past 4 weeks, how often has your child had…
…excessive daytime drowsiness or
1
2
3
4
5
6
sleepiness?
…poor attention span or
1
2
3
4
5
6
concentration?
…difficulty getting out of bed in
1
2
3
4
5
6
the morning?
Caregiver concerns
During the past 4 weeks, how often have the problems described above…
…caused you to worrying about
1
2
3
4
5
6
child’s general health?
…caused concern that your child is
1
2
3
4
5
6
not getting enough air?
…interfered with your ability to
1
2
3
4
5
6
perform daily activities?
…made you frustrated?
1
2
3
4
5
6
all of the
time
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
For each question above, parents or caregivers rated symptom frequency during the previous 4 weeks using a 7-point
ordinal scale.
101
Current treatment for childhood OSA
habitual-snoring-group (scales 6-7) is associated with
3.5 times higher risk for AHI >1 episode/h comparing
to never-snoring-group (scale 0).8 However, the OSA18 questionnaire does not accurately detect OSA, and
all children with snoring and symptoms/signs of OSA
should undergo PSG studies.2 Mouth breathing, night
enuresis, sleeping in a seated position or with the neck
hyperextended, cold sweating, cyanosis, headaches on
awakening, daytime sleepiness, ADHD, and learning
problems are other important clinical indictors of
OSA.2-4 Family history of OSA is also a clue to indicate
OSA.
At first clinic visit, anatomical abnormalities of
the upper airway and predisposing factors of OSA
should be carefully identified. Recommended items of
physical examination include underweight/overweight,
tonsillar hypertrophy, adenoid facies, allergic shiners,
micrognathia/retrognathia, high-arched palate, and
stridor should be identified.2-4 Direct inspection of the
mid-face, nose, tonsil, teeth, mandible, maxilla can be
easily performed. Tests for allergic rhinitis and asthma,
x-ray examinations of the head, and neck, and flexible
fibro-optic endoscopy of the upper airway should be
considered individually. Neuromuscular disorder (e.g.,
cerebral palsy, and Duchenne muscular dystrophy),
prematurity, failure to thrive, and hypertension should
be evaluated by physical examination. Moreover,
history of OSA-related medical conditions should be
taken.
Should a pediatric patient with habitual snoring has
any clinical indicator of OSA (Table 1), pediatricians
should obtain a PSG study or refer the patient to a sleep
specialist or otolaryngologist for a more extensive
evaluation..2 However, extremely long waiting periods
of PSG studies frequently stop clinicians and parents
to undergo this examination. Therefore, a quick PSG
arrangement may be made for (1) a child snores
habitually and has any of the OSA-associated medical
condition (Table 2), and (2) a snoring child has some
clinical indicators that suggest a high index of suspicion
for moderate-severe OSA. A regular arrangement may
be suitable for snoring children having equivocal
history and physical examinations.
Overnight in-laboratory PSG studies assess
respiratory and sleep distrubances objectively and
quantitatively.. However, the criteria of interpretation
for PSG have varied over time. The most recent
diagnosis criteria and equipment requirements for PSG
have been summarized in the American Academy of
Sleep Medicine (AASM) Manual in 2007.9 Apnea is
a pause in breathing lasting at least two respiratory
cycles with no airflow detected. An obstructive apnea
exhibits persistent respiratory effort present on the
chest or abdominal belt sensor. A central apnea exhibits
no effort present on the chest or abdominal sensor,
whereas a mixed apnea shows a combination of the
two. For clinical research, the AASM currently defines
a hypopnea as a respiratory event lasting at least two
respiratory cycles with either a 50% reduction in
the airflow amplitude compared to baseline, and
accompanied by desaturation ≥3%, an awakening, or an
arousal. The AASM hypopnea rules for adults include a
respiratory event lasting at least 10 seconds with (rule
A) ≥4% desaturation or (rule B) ≥3% desaturation or
arousal. Use of adult rule A results in fewer children
fulfilling the criteria for OSA, whereas both pediatric or
adult criteria rule B can be used in adolescents without
significant change diagnostic category between these
two criteria.10 Finally, AHI is defined as the mean
number of apneas and hypopneas per hour of total sleep
time.
If PSG data are available, diagnosis and severity
of childhood OSA can be confirmed and other SDB
disorders can be managed immediately. Moreover,
priority for treatment and step-wised therapy should be
decided according to the severity of PSG findings and
OSA-associated morbidities. Recently, the American
Academy of Otolaryngology-Head and Neck Surgery
Foundation issued a clinical practice guideline to
arrange a PSG for SDB prior to tonsillectomy in
children.11 These recommendations include: (1) Before
determining the need for tonsillectomy, the clinician
should refer children with SDB for PSG if they exhibit
certain complex medical conditions. (2) Clinicians
should advocate for PSG prior to tonsillectomy for
SDB in children without any of the comorbidities for
whom the need for surgery is uncertain or when there
is discordance between tonsil size and the severity of
SDB. (3) Clinicians should communicate PSG results to
the anesthesiologist prior to the induction of anesthesia
before operation. (4) Clinicians should admit children
with OSA documented on PSG for inpatient, overnight
monitoring after tonsillectomy if they are younger
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Lee LA, et al.
than age 3 or have severe OSA (AHI ≥10 episodes/h,
oxygen saturation nadir <80%, or both). (5) In children
for whom PSG is indicated to assess SDB prior to
tonsillectomy, clinicians should obtain laboratorybased PSG, when available.
Treatment
Adenotonsillectomy is recommended as the firstline treatment of OSA patients with adenotonsillar
hypertrophy. Although snoring and obstructed
episodes are greatly reduced by adenotonsillectomy,
residual morbidity is common. Meanwhile, nasal
continuous positive airway pressure (CPAP) is
currently recommended as the first-line treatment
for OSA children with additional co-morbidity
or complex disease.2-4 Weight control, antiinflammatory therapy, CPAP, oral appliance, rapid
maxillary expansion, supraglottoplasty, craniofacial
reconstruction, and tracheostomy are adjuvant
therapies to adenotonsillectomy in varying conditions.
For providing a brief scheme for the management of
childhood OSA, we categorize these treatments into
(A) first-line treatment (adenotonsillectomy, nasal
CPAP) and (B) second-line treatment (weight control,
anti-inflammatory therapy, oral appliance, rapid
maxillary expansion, supraglottoplasty, craniofacial
reconstruction, and tracheostomy).
Moreover, the studies of “treatment benefits”
and “treatment harms” are categorized in levels of
evidence according to the “The Oxford 2011 Levels
of Evidence”.12 A systematic review of randomized
trials or n-of-1 trials (level 1) is generally better than an
individual randomized trial or observational study with
dramatic effect (level 2). Non-randomized controlled
cohort/follow-up studies provide level 3 evidences.
Case-series, case-control studies, or historically
controlled studies are graded as “level 4”. Mechanismbased reasoning is graded as “level 5”.
Figure 1. Scheme for adenoidectomy, tonsillectomy, and adjunctive surgical procedures in childhood
obstructive sleep apnea
103
Current treatment for childhood OSA
(A)First-line treatment
Adenotonsillectomy
Adenotonsillectomy continues to be the firstline and principle treatment at our sleep center
because the most common cause of childhood OSA
is adenotonsillar hypertrophy. Adenotonsillectomy
is simple and efficient and has low morbidity for the
therapy of OSA. Adenotonsillectomy is associated
with a low complication rate (5% to 10%) in general
population, but its complication rate is significantly
higher in patients with OSA (18% to 34%; level 3).2
Accordingly, pre-surgical PSG has been suggested
to be necessary in guiding the intraoperative and
postoperative management in children undergoing
adenotonsillectomy. Patients with younger age
(<2 years), AHI >24 episodes/h, intra-operative
laryngospasm requiring treatment, oxygen saturations
<90% on room air in PACU, PACU stay >100
min, or OSA-associated morbidities are at risk for
postoperative complications (level 4).13 Common
post-adenotonsillectomy
complications
include
wound pain, poor oral intake, bleeding, infection,
anesthetic complications, respiratory decompensation,
velopharyngeal incompetence, and death; perioperative
complications should be prevented and managed
carefully.
Of note, a significant proportion of patients are left
with persistent OSA after adenotonsillectomy despite
improvement of polysomnographic parameters; that
is, the majority of moderate-severe OSA children
become mild OSA following adenotonsillectomy.5 Two
meta-analyses (level 1) suggest that the postoperative
AHI <5 episodes/h are frequently observed (range,
66.2%-82.9%).14,15 Friedman et al. demonstrated
that the pooled cure rate (i.e. postoperative AHI
<1 episode/h) of adenotonsillectomy was 59.8%.15
However, Bhattacharjee et al. found that the cure rate
was 27.2% in a larger multicenter retrospective study
(level 3).5 Marked differences in cure rates among
these outcome studies may be resulted from the
usage of published hypopnea definitions differently..
Moreover, approximate 13% of subjects who had been
successfully treated with adenotonsillectomy may have
recurrence of OSA at adolescence (level 3).16
Therefore, a combination of adenoidectomy,
tonsillectomy, and/or adjunctive surgical procedures
should be considered according to patient’s age,
obstructive sites, and OSA severity at our sleep center
(Fig. 1). Adenoidectomy is unlikely to be the sole
treatment of childhood OSA because it does not change
oropharyngeal obstruction that may be related to the
tonsils, and we recommend adenoidectomy as the
initial treatment for an infant (<1 year) with OSA and its
associated conditions since nasal breathing is obligatory
or at least strongly preferential in infants. Even relatively
small tonsils may rotate medially and superiorly to
obstruct the retropalatal airspace and narrow upper
airway (level 4).17 Moreover, childhood tonsillectomy
is related to neither the increasing frequency nor
the prolonged duration of upper respiratory tract
infection comparing with age-matched controls (level
3).18 Accordingly, simultaneous tonsillectomy and
adenoidectomy in cases of documented OSA seems to
be more rationale comparing to single adenoidectomy
in OSA patients older than 1 year.
Partial tonsillectomy has been more favoring
than before because of its relative low morbidity
comparing to traditional tonsillectomy.2 Microdebrider
intracapsular adenotonsillectomy, using a 10otonsillar
blade (Medtronic ENT, FL, USA), spares a portion
of tonsil to cover the musculature of the tonsillar
fossa and decreases the morbidity associated with
traditional tonsillectomy, seems to be as effective as
total tonsillectomy in treatment of childhood OSA as
validated by PSG (level 4).19 There exists a risk of
tonsillar regrowth and the patients with residual or
relapsing OSA may need a revised total tonsillectomy.
Accordingly, we recommend younger children
(<5 years) with mild-moderate OSA to undergo
adenoidectomy and partial tonsillectomy.
Several new techniques for alleviating the morbidity
associated with total tonsillectomy have gained
increasing use in recent years. Bipolar radiofrequency
dissection tonsillectomy a radiofrequency bipolar
forceps (El lman International, New York, USA) seems
to be associated with shorter operating time and minimal
intra-operative blood loss when compared to the
conventional cold dissection tonsillectomy in a level 2
study.20 A different bipolar radiofrequency-based plasma
device (Coblation®, ArthroCare Corp, CA, USA) also
proves its advantages (less intraoperative bleeding
and pain, similar minimal postoperative bleeding)
over cold dissection with sutures for the treatment of
104
Lee LA, et al.
children with OSA (level 2).21 In addition, coblation
total tonsillectomy in children is further confirmed to
be a reliable and safe procedure with a relatively low
incidence of intraoperative and postoperative bleeding
(level 3).22 In our institute, we recommend children (≥5
years) with high grade tonsillar hypertrophy and mildmoderate OSA to undergo complete adenotonsillectomy
with electrocautery or coblation.
Residual OSA is present in a large proportion of
children after adenotonsillectomy, particularly among
older (>7 years) or obese children (level 3).5 Friedman
et al.23 found that traditional adenotonsillectomy plus
pharyngoplasty with suturing the muscle layer of the
tonsillar wound to reduce the collapsibility of the
pharynx is associated with an insignificantly increasing
cure rate comparing to traditional adenotonsillectomy in
a randomized control trial with minor limitations (level
2). For these reasons, we recommend adenoidectomy
and total tonsillectomy with pharyngoplasty for
young OSA children. In some cases such as obese
adolescents or children with complex disease, modified
uvulopalatopharyngoplasty including removal of parts
of supratonsillar mucosa and adipose tissue may be
more suitable. Although the use of electrocautery is
not associated with an increase incidence of wound
dehiscence compared with cold dissection, we
observed tonsillar pillar dehiscence rate is particularly
high in coblation pharyngoplasty in pediatric subjects.
Recently, a randomized control trial (level 2) compared
the effectiveness of plasma knife, bipolar electrocautery,
and cold dissection, and concluded that the use of plasma
knife (PEAK PlasmaBlade™, Medtronic ENT, FL,
USA) reduces intraoperative blood loss and provides
a fast tonsillectomy with acceptable morbidity.24 The
sharp cutting edge incised by plasma knife looks like
that by cold knife, and allows surgeons to suture the
tonsillar pillar easily and precisely, and may prevent
from early wound dehiscence, pain, and bleeding.
Currently, we prefer to undergo adenotonsillectomy plus
pharyngoplasty or relocation pharyngoplasty (modified
uvulopalatopharyngoplasty)25 using electrocautery or
plasma knife for a child with OSA who has older age at
operation (>7 years), severe severity, obesity, or OSAassociated (co-morbidities).
Nasal CPAP
Currently, nasal CPAP is recommended for OSA
105
children unable to undergo adenotonsillectomy or
patients with residual OSA following other treatment
modalities (Table 4). 2-4 Stenting the pharyngeal lumen
by nasal CPAP in order to reduce the obstructive effects
caused by increasing upper airway resistance, raised
pharyngeal collapsibility, decreased pharyngeal dilator
muscle tone, and more negative intraluminal pressure
is indicated for all OSA patients. However, adherence
to CPAP treatment in childhood OSA is very poor
despite its high efficacy. Poor adherence to nasal CPAP
is a leading cause of therapeutic failure. Accordingly,
if adenotonsillectomy is an option to treat childhood
OSA, nasal CPAP can be reserved as a second-line
therapy.
Two level 2 study (randomized trial with low power)
assessed two different sleep respiratory therapies (CPAP
vs. bilevel positive airway pressure26 or CPAP vs.
bilevel positive airway pressure with pressure release
technology27), and found both treatment modalities can
improve the patients’ snoring, AHI, and arterial oxygen
saturation. About 39%-80% of patients adhere to nasal
CPAP therapy (levels 2-3).26-28 If the caregivers accept
nasal CPAP as a major treatment, behavioral techniques
may help to improve its adherence. The most frequently
endorsed barriers to CPAP were similar for parents and
their children: almost half of the families reported “not
using CPAP when away from home” as a top barrier.28
Of note, CPAP pressures and fitness of mask should
be periodically reassessed because various changes of
growth and development in children. In our institute,
a highly motivated team approach consisting of
physicians, nurses, psychologists, and sleep technicians
work jointly in corroboration is proposed to maintain
a CPAP adherence to promote high success rate of
management.
(B)Second-line treatment
Weight loss
Childhood OSA seldom resolves spontaneously but
may deteriorate gradually (level 4).29 The severity of
airway inflammation and sleep associated gas exchange
abnormalities increase with progressive obesity in older
children with OSA (level 3).30 Accordingly, weight
control should be stressed in the temporal management
of childhood OSA, particularly in elder children.
Anti-inflammatory treatment
The prevalence of OSA increases markedly among
Current treatment for childhood OSA
Table 4. Modalities of possibly curative treatment of childhood OSA
Levels of
Indications
evidence*
Reduce upper airway narrowing and its resistance:
Adenotonsillectomy 1-4
1. Adenotonsillar
hypertrophy
Modality
Reduce upper airway resistance and its collapsibility:
Nasal CPAP
2-4
1. OSA associated
with severe
complex (co-)
morbidities
2. Residual OSA after
adenotonsillectomy
3. OSA associated
with (co-)
morbidities that
fail to response
to other treatment
modalities
Supraglottoplasty
4
1. Laryngomalacia
Suggestions
1. Perioperative complications should be prevented
and managed carefully.
2. Residual disease is common.
3. Recurrent disease is not unusual.
1. Nasal CPAP should be prescribed as the first-line
treatment for children with complex disease or as
an adjuvant treatment following other treatment
modalities.
2. Poor adherence of nasal CPAP is common and
should be overcome by behavior modifications
and team approach.
3. CPAP pressures and fitness of mask should be
periodically reassessed.
1. Infant or young children with moderate
laryngomacia may have OSA.
2. Supraglottoplasty for laryngomalacia may also
improve co-existing OSA severity.
Reduce upper airway resistance and improve efficacy of neuromotor function
Oral appliance
2-4
1. Small mandible
1. Mandibular advancement devices and rapid
2. Retrognathesia
maxillary expansion can help to change the
narrowing upper airway and can be used to treat
Rapid maxillary
2-4
1. High narrow
mild-moderate OSA.
expansion
maxilla
2.
Distraction osteogenesis is usefully applied in
Distraction
4
1. Mandibular
congenital micrognathia or midface hypoplasia.
osteogenesis of
hypoplasia
3.
Consistent follow-up and management are
the mandible and
2. Midface deficiency
needed to increase clinical success rates in dental
midface
or craniofacial treatment of OSA.
Bypass the upper airway obstruction
Tracheostomy
4
1. Intractable OSA
1. Tracheostomy is the most effective treatment for
2. Maintaining airway
severe and intractable OSA.
patency before
2. This modality is also the last choice reported by
surgery
parents.
OSA: obstructive sleep apnea. CPAP: continuous positive airway pressure.
*The studies of “treatment benefits” are categorized in levels of evidence according to the “The Oxford 2011 Levels of
Evidence”.60
106
Lee LA, et al.
children with history of allergic rhinitis, wheezing,
and poorly controlled asthma (level 3).31,32 Moreover,
viral respiratory infections may induce inflammation
and oxidative stress in the allergic airway enhancing
leukotrienes within pharyngeal lymphoid tissues,
which promote adenotonsillar enlargement and OSA.31
Appropriate treatment of allergic rhinitis regularly
can prevent the occurrence of OSA and reduce the
severity of existing OSA. Of note, intranasal steroids
may ameliorate mild-moderate OSA and provide a
short-term benefit effect (level 2) 33 but be not used
as the primary treatment of moderate or severe OSA.2
Because the long-term effects of intranasal steroids
are not known, it can use to be a short-term treatment
of OSA and follow-up evaluation is needed to ensure
that the OSA does not recur and to monitor for adverse
effects (level 1).34 In the past, montelukast have been
reported to induce significant reductions in adenoid size
and respiratory-related sleep disturbances in a small
level 3 study,35 but it has not been recommended to be a
single treatment of OSA because of insufficient data.34
In the most recent randomized control trial, a 12-week
treatment with montelukast effectively reduced the
magnitude of the underlying adenoidal hypertrophy and
the severity of OSA (obstructive apnea index decreased
by >50% in 65.2% of treated children) comparing with
placebo in children with mild-moderate OSA (level
2).36
Supraglottoplasty
Most children with laryngomalacia have breathing
disturbance in daytime, but some children may
present normal breathing while awake but stridor and
increased work of breathing during sleep. PSG should
be considered in the initial evaluation of infants with
moderate laryngomalacia to rule out OSA (level 4).37
Moreover, laryngomalacia may contribute significantly
to OSA in children older than 12 months (level 4).38
Drug-induced sleep endoscopy under light sedation
can help to diagnose state-dependent laryngomalacia.
When children with laryngomalacia and OSA is
diagnosed, a supraglottoplasty can be an effective
procedure and may significantly improve symptoms
of OSA in three level 4 studies.37-39 The primary
complications after supraglottoplasty are dysphagia,
postoperative coughing, and throat clearing, those are
transient in most children (level 4).39
107
Oral appliance
Children with malocclusion and OSA have a narrow
upper airway at the level of the mandible, tongue, and
soft palate. Using an oral jar-positioning appliance
to reposition these structures resulted from the small
mandible or retrognathesia can help to maintain the
patency of the upper airway during sleep. A randomized
control trial (level 2) have shown that an oral appliance
is more effective than observation only to treat OSA
in children.40 The most frequent reasons why patients
discontinued wear are uncomfortable, having little or
no effect, or switching to nasal CPAP; side effects,
such as dry mouth and tooth and/or temporomandibular
joint discomfort are frequently reported (level 4).41
We recommend the oral appliance as a therapeutic
alternative in children with mild to moderate OSA.
Consistent follow-up and management are needed to
increase clinical success rates in oral appliance therapy
for OSA.
Rapid maxillary expansion
Rapid maxillary expansion to correct the narrowed
maxilla and malocclusion has been used to treat
childhood OSA for many years. AHI and arousal
index can be reduced by rapid maxillary expansion
significantly in the first year and may persist 24 months
after the end of treatment (level 4).42 However, rapid
maxillary expansion may fail as a mono-therapy for
OSA in patients with both adenotonsillar hypertrophy
and narrowed maxillary complex. The orthodontic goal
for these patients should include strategies to improve
the narrowing upper airway while still achieving a
functional occlusion. Guilleminault and his coworkers
have undergone a randomized control trial to compare
the outcomes of adenotonsillectomy followed by rapid
maxillary expansion and rapid maxillary expansion
followed by adenotonsillectomy (level 2).43 They
found the differences in outcomes between both groups
were statistically insignificant and continued clinical
symptoms and abnormal PSG results frequently
persisted in overall patients. Accordingly, mandibular
advancement devices are recommended to be used for
mild to moderate OSA.
Distraction osteogenesis of the mandible and
midface
A high degree of suspicion in the population
craniofacial anomalies is necessary to rule out the
Current treatment for childhood OSA
existence of OSA in a given pediatric patient. Childhood
OSA associated with craniofacial anomalies frequently
is refractory to traditional treatment modalities.
Severe mandibular hypoplasia and midface deficiency
can cause extreme narrowing of the upper airway
and may be managed by tracheostomy in the past.
Distraction osteogenesis of the mandible and midface
can enable mandibular and midfacial lengthening
and relieve severe upper airway obstruction; these
surgical approaches may lead to earlier decannulation
and treat abnormal sleep breathing. When comparing
newborns and early infant patients, treatment success
rates and the occurrence of complications following
distraction osteogenesis seems to be similar; however,
older pediatric patients may have no treatment failures
and tend to have fewer postoperative complications
compared to younger patients (level 4).44
Successful mandibular advancement can increase
mandibular volume by an average of 28% and increase
upper airway volume with a mean of 72%, and also can
improve apnea index and arterial oxygen saturations
(level 4).45 Le Fort III osteotomy with midface
distraction osteogenesis can significantly improve the
upper airway space above the uvula level in the cases
of syndromic craniosynostosis and may ameliorate the
severity of childhood OSA (level 4).46 Despite midface
advancement, long-term dependence on, or indication
for, CPAP or tracheostomy may be maintained in near a
half of this population.47
Tracheostomy
Childhood OSA complicated by congenital
craniofacial malformations is frequent rigorous, which
in severe cases leads to tracheostomy dependence. A
tracheotomy can bypass upper airway obstruction and
is extremely effective at treating OSA. However, this
surgical approach is associated with increased morbidity
and is typically a last resort if CPAP and other treatments
fail to improve for a child who has severe OSA.2-4 Even
in OSA children with syndromic craniosynostosis,
adenotonsillectomy can avoid of tracheostomy in three
of five patients (level 4).48 Distraction osteogenesis
may be a useful method to improve the airway, to avoid
the tracheostomy, or to lead decannulation. However,
decannulation rate of the permanent tracheostomy
following mandibular distraction osteogenesis seems
to be varied differently in tracheotomized patients with
complex congenital syndromes (13%-100%).46,49
Follow-up
There are many treatment modalities to date, but
there is no “one-size-fits-all” approach due to the
multifactorial nature of childhood OSA. Even though
adenotonsillectomy is the first-line treatment, residual
OSA (AHI ≥5 episodes/h) may have frequently existed
in 8%-34% subjects in previous meta-analyses.14,15
The BMI gain soon after operation6 and may result in
recurrence of OSA.16 Accordingly, we recommend a
period of observation following adenotonsillectomy is
imperative even for younger OSA children.
Of note, an average prevalence of residual OSA has
reported to be 73% in a large multi-centric retrospective
study5 when using an postoperative AHI ≥1 episodes/h.
To our knowledge, obstructive apneas are frequently
reduced by adenotonsillectomy, whereas hypopneas
often persist postoperatively and result in residual OSA.7
Despite different definitions of hypopnea and residual
OSA, skeletal abnormalities such as craniofacial
anomalies, minor stenosis, or neuromuscular disorders,
obesity, a high preoperative AHI (≥20 episodes/h), as
well as an old age at surgery (>7 years) are important
risk factors of persistent OSA.5 It is important to realize
that adenotonsillectomy often does not achieve desired
results in childhood OSA. Therefore, a longitudinal
follow-up of OSA children with the risk factors
listed above is able to reveal residual of respiratory
disturbance after adenotonsillectomy and to suggest reevaluation of OSA-associated (co-)morbidities.
Amin et al. have performed serial PSGs, BMI, and
blood pressure examinations after adenotonsillectomy
during the first 1 year.16 They found that AHI reduced
from 9.2±14 episodes/h at baseline to 1.4±2 episodes/h
at 6 weeks after surgery and their AHI increased
gradually overtime. At 1 year postoperatively, the
recurrence of OSA (AHI ≥3 episodes/h) seems to be
associated with an accelerated BMI gain, obesity, and
African American. Moreover, allergic rhinitis, regrowth
of adenoid, craniofacial anomaly with abnormal
bite, and lingual tonsil hypertrophy are also related
to persistent or recurrent OSA. Noticeably, complete
resolution of OSA in patients with complex disease
such as Prader-Willi syndrome is difficult to obtain with
adenotonsillectomy alone.50 OSA patients identified
with Prader-Willi syndrome should be referred for
adenotonsillectomy and/or CPAP therapy, and then
108
Lee LA, et al.
reassessed for residual airway obstruction and/or OSA
prior to instituting growth hormone therapy.
Absence of symptoms such as snoring postoperatively
is reassuring but may not be 100% specific for complete
resolution of OSA. By contrast, postoperative reports
of snoring and witnessed apneas correlate well with
persistence of OSA after adenotonsillectomy.51 It
may therefore be advisable to obtain a postoperative
PSG in (1) very high-risk children even in the
absence of reported persistent snoring or (2) patients
with persistent or recurrent symptoms and signs of
OSA. Nevertheless, “surgical success” should be
defined not only by PSG but also by resolution of
clinically relevant outcomes, such as cardiovascular
function, neurocognition, behavior, and quality of
life.7,52 Therefore, establishment of standardized data
collection procedures, establishment of equipoise,
and approaches for minimizing unblinding of selected
key personnel are major elements in the design and
implementation of a fine controlled trial for a widely
used “standard practice” surgical intervention in a
pediatric OSA population.
CONCLUSION
Childhood OSA is a prevalent disease in the world.
Clinical indicators can help pediatricians to decide
whether or not a child is at risk for childhood OSA.
Early consultations for a pediatric dentist, craniofacial
surgeon, neurologist, cardiologist, or psychiatrist are
particular important for intensive management of
OSA-associated underlying disease and morbidities.
Timely diagnosis and treatment of orthodontic
problem, craniofacial anomaly, neuromuscular
disorder, cardiovascular disorder, or ADHD are
imperative because these diseases may trigger the
occurrence of OSA or also may be aggravated by OSA.
The true mechanism of childhood OSA is probably
multifactorial and differentiation of the primary and
secondary aspects enables clinicians to pinpoint the
essentials of childhood OSA. To date, standard PSG is
the “golden standard” diagnostic method for pediatric
SDB and adenotonsillectomy continues to be the best
and most acceptable treatment for childhood OSA.
Despite there are many other treatment modalities such
as nCPAP, weight loss, anti-inflammatory treatment,
109
supraglottoplasty, oral appliance, rapid maxillary
expansion, distraction osteogenesis, and tracheostomy
for childhood OSA, residual disease is quite common
after any mono-therapy. Of note, persistence or
recurrence of OSA is not unusual and therefore indicates
a necessity of a personalized re-evaluation.
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