We introduce the causes and clinical manifestations of obstructive sleep apnea hypoventilation syndrome (OSAHS) in children, describe the effects of OSAHS on the pediatric patient’s organism, propose the key points of clinical diagnosis and treatment principles of OSAHS, and evaluate the prognosis.
Obstructive sleep apnea hypoventilation syndrome (OSAHS) in adults has been more widely recognized, but OSAHS in children has not received sufficient attention.
The prevalence of OSAS in preschool children ranges from 1% to 3% and can be complicated by a variety of diseases. The etiology, clinical manifestations, polysomnographic features, prognosis and principles of diagnosis and treatment of OSAHS in children are different from those in adults.
I. Etiology of OSAHS in children
The most common cause of OSAHS in children is adenoid tonsillar hypertrophy, and obesity is uncommon in pediatric patients. Other less common causes are: nasal stenosis, posterior nostril closure, post-operative cleft palate, tongue enlargement, mandibular recession, small jaw, various diseases causing laryngeal stenosis, Down’s syndrome, etc.
Basic clinical manifestations
At night, snoring, labored breathing, abnormal chest and abdominal breathing, apnea, restless sleep, and urination are manifested. During the daytime, the symptoms are nasal congestion, open-mouth breathing, irritability and inability to concentrate, while drowsiness is not common.
Comparison of adult and pediatric OSAHS patients
Child patients
1. Generally continuous uniform snoring
2. Generally no daytime sleepiness
3. Generally no obesity
4.Growth retardation, low weight
5. Daytime open-mouth breathing is common
6. No gender difference in onset
7.Tonsillar adenoid hypertrophy is common
8, mainly hypoventilation
9. Hypoventilation is usually not accompanied by microarousal at the end of hypoventilation
10.Sleep disorders are uncommon
11, Complications: cardiovascular and respiratory system, developmental delay, abnormal behavior
12.Surgical treatment, i.e. adenoid tonsillectomy, is the main treatment, and continuous positive pressure ventilation is rarely used
Adult patients
1.Snoring is variable and intermittent
2.Daytime sleepiness is the main symptom
3.Usually have obesity
4.Not reported
5.Rarely seen open-mouth breathing during daytime
6.The ratio of male to female is 8-10/1
7.Tonsillar adenoid hypertrophy is uncommon
8.Apnea is the main cause
9.Apnea is usually accompanied by micro-awakening at the end of apnea
10, sleep disorders are common
11, Complications: cardiovascular and respiratory system
12.Select case surgery, continuous positive pressure ventilation treatment is important
13.Sleep death, cardiovascular disease
III. Diagnostic criteria
Polysomnography is the gold standard for definitive diagnosis. The American Academy of Pediatrics currently recommends that apnea in children be defined as greater than or equal to 2 respiratory cycles without oral and nasal airflow, while the criteria for hypoventilation are generally adopted for adults, i.e., a 50% drop in respiratory airflow for 10 seconds, accompanied by a 3% drop in oxygen saturation or microarousal. Pediatric patients have fewer apneic events and a shorter duration of maintenance, while partial upper airway obstruction occurs for a relatively long time.
OSAHS is diagnosed with an apnea index (AI) of ≥ 1 breath/h or an apnea hypoventilation index (AHI) of ≥ 5 breaths/h.
This diagnostic criterion is currently controversial.
The effects of OSAHS on the pediatric patient’s body
1. Cardiovascular system
Severe OSAHS can lead to pulmonary heart disease and congestive heart failure, and left heart failure has also been reported. After the development of pulmonary heart disease, the reasonable treatment of OSAHS can make the symptoms of pulmonary heart disease disappear. It has been reported that 37% of pediatric patients with OSAHS have decreased right ventricular ejection fraction.
However, the number of severe arrhythmias and hypertension associated with OSAHS in children is significantly less than that in adults.
2. Growth and development
Severe patients and patients with other comorbidities may have impaired growth. In general patients there can be organic developmental effects (increased growth rate after surgery), but no developmental disorders.
3.Cognitive function of the nervous system
Learning ability, attention and psychological aspects are significantly affected in children with OSAHS.
4.Impact on craniofacial development
Long-term open-mouth breathing causes open jaw, high arched palatal lid, and narrowed nasal cavity.
V. Basic principles of diagnosis and treatment of OSAHS in children
1. Diagnosis
History taking and physical examination are very important. However, the diagnosis cannot be made clearly based on history and physical examination alone. For example, severe snoring does not necessarily mean the presence of OSAHS, and enlarged tonsils and adenoids do not necessarily mean the presence of OSAHS.
Polysomnography (PSG) is still the gold standard for definitive diagnosis. PSG is recommended when available.
PSG is recommended for severe patients, especially those with other comorbidities, to clarify the severity of the condition and to fully understand the condition before treatment. However, if the patient’s condition is urgent, such as combined with respiratory or heart failure, it is not necessary to do PSG test first.
2.Treatment
Tonsil adenoidectomy is the most important treatment measure. The surgical cure rate is 75%-100%. It is recommended that surgery be performed under general anesthesia with transoral intubation, and that the adenoids be scraped out completely under direct nasal vision using a nasal endoscope or otoscope.
The risk factors for complications are: age less than 3 years, AHI ≥ 10 times/h, developmental disorders, combined pulmonary or neuromuscular diseases, and craniofacial developmental malformations.
Those who are not suitable for surgery or failed surgery can be treated with continuous positive pressure ventilation (CPAP). Some patients require orthodontic treatment.
Follow-up is performed after surgery, and PSG must be reviewed in severe patients.
VI. Research outlook
The research directions about OSAHS in children mainly include the following aspects: through a large number of epidemiological surveys, analysis of risk factors for complications arising from OSAHS in children and clear standardization of diagnostic criteria for OSAHS; improvement of diagnostic equipment, screening and diagnostic equipment should be economical, sensitive and practical; exploration of long-term differences between treated and untreated groups of children with primary snoring and OSAHS, and assessment of The long-term efficacy of various treatment measures.