History

Snoring is the primary complaint of children presenting to the otolaryngologist; the prevalence has been reported as 3–12% in children,² although some studies suggest that the rate may be as high as 27%.³ Primary snoring has implications with associated morbidity of elevated blood pressure and reduced arterial distensibility.⁴ Approximately 40% of children who snore have more significant manifestations with obstructive sleep apnea (OSA). Additional complaints may include mouth-breathing, breath-holding, and gasping.⁵ Sleep is disrupted by episodic arousals resulting from partial obstruction of the upper airway. Manifestations include morning headache, dry mouth, halitosis, and behavioral and neurocognitive disorders less commonly sleepwalking, parasomnoliloquy, enuresis, night terrors, or bruxism.^5,6 Dysphagia may occur with significant tonsil enlargement. Children may avoid certain foods that are more difficult to swallow. Major predisposing factors identified in upper airway obstruction include: anatomic narrowing, abnormal mechanical linkage between airway dilating muscles and airway walls, muscle weakness, and abnormal neural regulation.⁷ Complications related to severe OSA include cor pulmonale, right ventricular hypertrophy, congestive heart failure, hypoventilation, pulmonary hypertension, pulmonary edema, and failure to thrive.⁸ History alone is insufficient to diagnose OSA. Symptoms often worsen during REM sleep when parental observation is absent.⁹ A polysomnogram (PSG) is the gold standard in differentiating between the spectrum of snoring, increased upper airway resistance, and OSA.

Infants with upper airway obstruction can present with stridor. This worsens with activity or feeding. Inspiratory or biphasic stridor may indicate laryngomalacia, vocal fold dysfunction (VCD), or supraglottic lesions.¹⁰ Biphasic or expiratory stridor may indicate VDC, a lower airway lesion such as subglottic stenosis or tracheobronchomalacia.¹⁰ Concerning symptoms include retractions observed apneic episodes, cyanosis, and failure to thrive. Previous history of intubation and prematurity are specific risk factors for obstructive airway lesions.¹¹

Other factors may place a child at risk (Table 33.1). Obesity is a risk factor that may cause fatty infiltration of the pharyngeal soft tissues, which narrows the upper airway and contributes to airway resistance and reduced lung volume.^12,13 The prevalence of OSA in children with Down syndrome ranges between 31% and 100%,¹⁴ and may be related to hypotonia, relative macroglossia, midfacial and mandibular hypoplasia, a narrow nasopharynx, and a shortened (high-arched) palate.¹⁵ Children with other craniofacial syndromes and abnormalities also have a higher prevalence of OSA. Robison and Otteson¹⁶ found that 172 out of 459 (37.5%) children with nonsyndromic cleft palate had symptoms of OSA, and that 39 (8.5%) had a positive PSG. Children with Apert, Crouzon, Nager, and Pfeiffer syndromes have a high rate of OSA.^17,18 Other medical conditions with a high risk for the development of OSA include mucopolysaccharide disease, vascular malformations of the head and neck, and children with neuromuscular disorders.

OSA may exacerbate underlying medical conditions such as congenital heart disease, pulmonary disease, and sickle cell disease (SCD). In SCD, adenotonsillar hypertrophy or recurrent tonsillitis is frequently linked with an increased risk of OSA, cerebrovascular ischemia, or frequent pain episodes, and often require an adenoidectomy and/or tonsillectomy.¹⁹ Adenotonsillectomy has been demonstrated to be cost-effective for treating obstructive sleep apnea and preventing cerebrovascular ischemia without increasing vaso-occlusive pain episodes or long-term acute service costs in routine clinical practice settings.

Physical Examination

The general appearance of the child provides a great deal of information. An open mouth posture and stertorous or sonorous breathing may indicate upper airway resistance. Examination of the craniofacial skeleton may reveal deformities such as midface hypoplasia or mandibular hypoplasia. Some children present with failure to thrive due to difficulty in coordinating feeding and breathing or dysphagia related to tonsillar hypertrophy.

On routine examination, nasal mucosa, turbinates, septum, and nasal cavity may demonstrate septal deviation, inflamed, edematous mucosa, and inferior turbinate hypertrophy. The nasal passages should be inspected for masses or polyps. No single feature defines OSA in children.

Oral cavity examination should include evaluation of the tonsils, tongue and palate. Tonsil grading is typically on a scale of 0 (surgically absent) to 4 (tonsils touching each other) (Figure 33-1). The static pressure and/or area relationships of the passive pharynx were endoscopically measured in 14 children with obstructive sleep apnea and in 13 healthy children under general anesthesia with complete paralysis; it was determined that children with obstructive sleep apnea closed their airways at the level of enlarged adenoids and tonsils at low positive pressures, whereas healthy children required subatmospheric pressures to induce upper airway closure.²⁰ The cross-sectional area of the narrowest segment was significantly smaller in children with obstructive sleep apnea and particularly in the retropalatal and retroglossal segments. Thus, both congenital and acquired anatomic factors clearly play a significant role in the pathogenesis of pediatric obstructive sleep apnea. Macroglossia, such as in the case of Down syndrome or Beckwith–Wiedermann, may be contributory to upper airway obstruction. The appearance of the palate should be noted, as an elongated palate may also play an important role in obstruction, particularly after adenotonsillectomy (Figure 33-2).

Flexible endoscopy is an important tool that can allow for comprehensive evaluation of the upper airway in infants and children. This may be performed in the office in an awake child or with anesthesia. Lidocaine is used for topical anesthesia and oxymetazolone for decongestion to increase the comfort for this examination. Sites of obstruction may occur anywhere from the tip of the nose to the glottis. Therefore endoscopy can be used to visualize the nasal passages, nasopharynx, oropharynx, hypopharynx, and larynx. Nasal patency is assessed for nasal septal deviation, turbinate hypertrophy, polyps, or masses. Choanae are evaluated for stenosis or atresia. Adenoids may be visualized for hypertrophy. Oropharyngeal and hypopharyngeal examination provides a view of the posterior aspect of the tonsils and base of tongue. Tonsils may appear normal during an oral cavity exam. However, the tonsil pole may be elongated or posteriorly displaced and occupy a significant portion of the hypopharynx. Base of tongue enlargement may result in effacement of the vallecular with compression and displacement of the epiglottis posteriorly. Enlargement of the lingual tonsils at the tongue base is increasingly recognized as a treatable cause of OSA. Obese children have a high frequency of enlargement of the lingual tonsils with a significantly higher prevalence in those with previous tonsillectomy,²¹ as demonstrated by MRI. Flexible endoscopy with the child in a supine position may further highlight narrowing at the level of the hypopharynx. Collapse of the lateral pharyngeal walls during inspiration with a closed airway (mouth shut and nostrils occluded) may be noted. The supraglottic structures are evaluated for laryngomalacia, as identified with epiglottis and/or arytenoids prolapse over the glottis. The vocal folds are assessed for mobility and masses.

Polysomnogram

Although history, physical examination, and flexible endoscopy of the airway are important tools, these cannot fully simulate the complexity of airway dynamics during sleep. Polysomnogram (PSG) is a valuable asset in assessing breathing. Indications for PSG have been outlined in the Clinical Practice Guideline developed by the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS).²² Children with complex medical conditions such as obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or mucopolysaccharidoses may benefit from preoperative PSG. PSG may be indicated in children for whom the need for surgery is uncertain, such as in the case of tonsillar hypertrophy and lack of sufficient history or when significant symptoms are present in the face of a negative physical examination.²² Prior to surgical intervention and anesthesia induction, the results of the study should be relayed to the anesthesia team. Inpatient admission after surgery should be considered for children under the age of 3 years or with severe OSA by PSG (apnea–hypopnea index of 10 or more obstructive events/hour, oxygen saturation nadir less than 80%, or both).^23,24 Intensive care unit monitoring may be warranted in a child with very severe OSA, medical comorbidities that cannot be managed on the floor, and those who demonstrate significant airway obstruction and desaturation in the initial postoperative period that requires interventions beyond repositioning and/or oxygen supplementation.²²

Imaging

Plain radiography with a high-kilovoltage lateral neck film may be used to evaluate for adenotonsillar hypertrophy in a child who is difficult to examine or when a caregiver defers flexible endoscopy. Adenoid hypertrophy visualized by lateral neck radiograph correlates well with flexible nasopharyngoscopy.²⁵ Most techniques focus on the size of the nasopharyngeal stripe, which indicates the amount of airflow through the nasopharynx. When the nasopharyngeal stripe is half the size of the soft palate, significant obstruction occurs. However, the actual size of the adenoid pad is not as relevant as the amount of obstruction caused by hypertrophy.

Anterior–posterior high-kilovoltage neck films evaluate the laryngeal suprastructure and subglottis. Cephalometry and computed tomography are useful in evaluating children with craniofacial disorders. Research suggest that there are evident and early changes in facial growth and development among children with OSA, characterized by increased total and inferior anterior heights of the face, as well as a more anterior and inferior position of the hyoid bone.²⁶ Chest radiography may help identify evidence of pulmonary hypertension or right ventricular hypertrophy in a child with severe OSA.²⁷

Cine magnetic resonance imaging is a useful radiographic adjunct to the physical examination because it allows the clinician to screen for and to observe airway collapse in three planes (axial, coronal and sagittal).28,29 This is particularly helpful in isolating anatomic sites of airway obstruction in children who have persistent apnea after adenotonsillectomy (Tonsillectomy and Adenoidectomy).

Additional Testing

Patients with severe OSA or abnormal electrocardiogram findings on PSG warrant a complete electrocardiogram. Electrocardiographic findings are not specific for pulmonary hypertension or right ventricular hypertrophy but may include voltage or axis abnormalities, a t-wave pattern (strain pattern), or mixed criteria. On occasion, a normal electrocardiogram may occur even with echocardiographic findings of pulmonary hypertension.²⁷ Laboratories are not routinely ordered prior to Tonsillectomy and Adenoidectomy unless a history is concerning for a bleeding disorder.³⁰ Patients who have a history of easy bruising and prolonged bleeding warrant a CBC/PT/T. Arterial blood gas analysis in conjunction with PSG may demonstrate hypoxemia or hypercarbia. Chronic hypercarbia may be associated with a compensatory metabolic alkalosis.²⁷

Intranasal Steroids

Intranasal steroids may be helpful if adenoid hypertrophy is the predominant cause of mild OSA in children. Decreases of 29% in adenoid size and 82% in symptom scores were noted in one study.³² Another study assessed a 6-week course of intranasal steroids,³³ reporting a significant improvement of the AHI post-treatment compared to the placebo group. Results may be maintained 8 weeks after completion of active treatment.³⁴ Intranasal steroids have not been found to impact tonsil size.³³

Twenty-four children with residual OSA (AHI >1 and <5/hour) were treated with montelukast and intranasal budesonide aqueous solution for 12 weeks.³⁵ This combined anti-inflammatory therapy effectively improved and/or normalized respiratory and sleep disturbances in children with residual SDB after adenotonsillectomy.

Systemic steroids have been tried in non-acute adenotonsillar hypertrophy. A short-term decrease in tonsil size has been noted, but long-term improvement and avoidance of surgery are usually not seen.³⁶ Although there is indication that intranasal steroids and monteleukast may be helpful in mild OSA, pharmacologic agents have no significant and persistent effect in the treatment of moderate to severe OSA in children.

Oral Appliances

Villa et al. randomized children with OSA and dysgnathia to either a personalized jaw-positioning oral appliance for 6 months or no intervention.³⁷ The authors reported that the AHI in the intervention group decreased significantly from 7.1 to 2.6/h. The oral appliance significantly lowered parent-reported snoring and apnea. A few of the patients had excessive salivation that subsided spontaneously. A Cochrane review (2007) on oral appliances and functional orthopedic appliances for OSA in children 15 years old or younger reported that there is insufficient evidence to state that oral appliances or functional orthopedic appliances are effective in the treatment of OSA in the majority of children. However, they may be helpful in the treatment of children with craniofacial anomalies that are risk factors of apnea.³⁸