Obstructive Sleep Apnea (OSA)

Definition

Obstructive sleep apnea (OSA) is a common pediatric disorder that classically presents with triad of snoring, evidence of breathing difficulties during sleep, and respiratory pause or apnea during sleep due to upper airway obstruction.

Diagnostic Criteria

(The Internation Classification of Sleep Disorders, Revised. American Academy of Sleep Medicine, 2005)

1. The patient (or parents of patient) has a complaint of excessive sleepiness or insomnia.  The patient may be unaware of clinical features that are observed by others.
2. Frequent episodes of obstructed breathing occur during sleep.
3. Associated features include:
   1. Loud snoring
   2. Morning headaches
   3. A dry mouth upon awakening
   4. Chest retraction during sleep in young children
4. Polysomnographic monitoring demonstrates:
   
   1. More than five obstructive apneas, greater than 10 seconds in duration per hour of sleep and one or more of the following:
      1. Frequent arousals from sleep associated with the apneas
      2. Bradytachycardia
      3. Arterial oxygen desaturation in association with the apneic episodes
   2. MSLT may or may not demonstrate a mean sleep latency of less than 10 minutes.
5. The symptoms can be associated with other medical disorders (e.g., tonsilar enlargement).
6. Other sleep disorders can be present (e.g., periodic limb movement disorder or narcolepsy).

Sub-types

There are typically two types of children who develop OSA:  Obese children who develop OSA secondary to their obesity, and non-obese children who develop OSA due to an anatomic anomaly.  It is possible a child could fall into both groups. 

Non- Obsese Group: Structural/neuromuscular abnormality causing upper airway obstruction

Etiology

1. Increased adenoid and tonsil tissue: The greatest incidence is from 2-5 years of age when the tonsil and adenoid tissue is relatively greatest in size and the frequency of URIs is highest
2. Midline craniofacial abnormalities-Aperts, Pierre Robin, Crouzon, Treacher Collins Syndromes
3. Large tongue or micrognathia
4. Congenitally narrowed airways, choanal narrowing, airway obstruction of any cause
5. Muscle weakness and hypotonia- Down Syndrome, Muscular Dystrophy, cranial nerve abnormalities, neuromuscular disorders, Arnold chiari Malformations.
6. Sedation and anesthetic agents

Clinical Features                                          

 Example 1        Example 2

1. History of restless sleep, increased respiratory efforts, gasping, and choking, and unusual sleep position
2. Daytime hyperactivity
3. Failure to thrive
4. Unusual sleeping positions to maintain patent airway
5. Symptoms may worsen with URI
6. Physical Findings
   
   1. Thin child
   2. Abnormal oropharnyx on exam, “mouth breathing at rest”
   3. Craniofacial abnormalities:
      
      1. Oropharngeal crowding
      2. Midface hypoplasia
      3. Macroglossia
      4. small jaw: high arching palate, overbite, crossing incisors
   4. Hyponasal speech, hoarse speech
   5. Poor muscle tone on cranial nerve exam
   6. Pectus excavatum

Treatment

1. Tonsil and adenoidectomy. May lead to cure but reoccurrence do happen especially if other risk factors like neuromuscular or craniofacial abnormalities exist. Must monitor carefully after surgery especially in younger patients and repeat sleep study. 
2. Nasal CPAP- compliance may be difficult at home
3. Upper airway surgery to repair anomalies
4. Tracheotomy may be necessary if CPAP doesn't work

OSA secondary to obesity: Pickwickian syndrome

Etiology:  Increased fat in nasopharynx requires more pressure to maintain airway while chest wall restriction leads to increased work of breathing.  Can present in any age group, usually greater than 5 years of age.  

Clinical Features

1. History of restless sleep, increased respiratory efforts, gasping, and choking, and unusual sleep position
2. Symptoms of daytime somnolence and restlessness (similar to adult OSA)
3. Symptoms may worsen with URI
4. Physical findings
   
   1. Obesity: BMI > 30 kg/m2
   2. May have evidence of airway obstruction while awake, “mouth breather”
   3. Hoarse voice or hyponasal speech

Treatment

1. Nasal CPAP- compliance may be difficult at home
2. Weight loss
3. Tracheotomy may be necessary if CPAP doesn't work

Lab findings in OSA

1. Polycythemia
2. Metabolic alkalosis
3. RVH, LVH on ECG

Complications in OSA

1. Growth failure
2. Pulmonary hypertension
3. Systemic Hypertension
4. Right heart failure and arrythmias
5. Behavioral and school problems secondary to sleep deprivation
6. Eneuresis

Differential Diagnosis of OSA

1. Other sleep disorder
2. GERD
3. Asthma
4. Persistent (day and night) upper airway obstruction (e.g Sub-glottic stenosis)
5. Nocturnal seizures

References

1. Man GCW. Obstructive Sleep Apnea: Diagnosis and Treatment. Medical Clinics of North America. 1996; 80(4):803-820.
2. Marcus, Carole. "Does your Child Snore?" Contemporary Pediatrics. Februrary 1998.
3. Corbo M, et al.  Snoring in 9 - 15 Year-Old Children:  Risk Factors and Clinical Relevance. Pediatrics Vol. 108 No. 5 Pg 1149.
4. American Academy of Pediatrics Clinical Practice Guideline: Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome. Pediatrics Vol. 109 No. 4 Page 704 April 2002
5. Matiz Adriana. Apnea. Pediatrics in Review January 2003
6. Goldstein NA.  Clinical Assessment of Obstructive Sleep Apnea. Pediatrics July 2004
7. Nixon G. Planning Adenotonsillectomy in Children With Obstructive Sleep Apnea: The Role of Overnight Oximetry. Pediatrics Jan. 2004;113 e119-e25
8. Gigante J. Tonsillectomy and Adenoidectomy.  Pediatrics in Review June 2005
9. Baugh et al. Clinical Practice Guideline: Tonsilectomy in Children.  Otolaryngol Head Neck Surg 2011 Jan ;144(Suppl)S1-S30
10. Goldbart AD. Montelukast for Children with Obstructive Sleep Apnea: a Doulble-blind Placebo Controlled Study.  Pediatrics July 2012
11. Marcus C. et al. Diagnosis and Management of Obstructive Sleep Apnea Syndrome. Pediatrics September 2012