Logo for University of Iowa Health Care This logo represents the University of Iowa Health Care
New Addition: * Course Announcement - Pediatric Airway (Online August 6,7 2021)Click Here

Obstructive Sleep Apnea (OSA)

last modified on: Wed, 01/03/2018 - 15:13

Return:  Clerkship Objectives and Exam Topics Review

BACKGROUND: 

  • There are multiple etiologies for sleep apnea syndromes, the three main types are: obstructive, central, and mixed. This page will focus on obstructive sleep apnea
  • Affects approximately 4% of adult males and 2% of adult females
  • Characterized by airway obstruction leading to episodes of disrupted or shallow breathing known as apnea spells
    • Apnea spells cause a brief arousal from sleep, followed by restored breathing and return to sleep
    • This obstruction/arousal/sleep cycle repeats throughout the night
  • In adults,  obesity is the key risk factor with obstruction typically due to increased fat deposition in the soft tissues of multiple levels of the pharynx and hypopharynx
  • In children: Enlarged tonsils and adenoids are the most common source of airway obstruction in children and result in sleep-disordered breathing

 

Signs and Symptoms:

  • Observed obstruction or apnea spells commonly manifesting as choking and gasping for air during sleep
  • Daytime lethargy
  • Morning headaches
  • Mood changes: irritability, depression, anxiety, short temper
  • Behavioral problems: poor school performance and hyperactivity
  • Growth retardation
  • Nocturnal enuresis
  • Pulmonary and cardiac disease

 

Risk Factors:

  • Obesity
  • Down Syndrome: particularly severe OSA in this population
  • Nasal Obstruction (due to deviation, chronic sinusitis, enlarged turbinates, narrow nasal passages, etc.)
  • Adenoid and tonsillar hypertrophy
  • Macroglossia
  • Hypothyroidism

 

DIAGNOSIS:

  • Adults:
    • The gold standard is in-lab polysomnography (PSG)
      • Apnea is defined as cessation of airflow for 10 seconds
      • Hypopnea has been defined in different ways, but generally a >30% decreased airflow due to obstruction with an associated >4% desaturation
      • Apnea-Hypopnea Index (AHI) is calculated by adding the number of apneas and hypopneas in one hour
      • AHI 5-15= mild, 16-30=moderate, >30= severe
  • The AHI from the PSG is an important aspect of treatment decision making, but ultimately it is taken in the context of symptoms, sleep architecture, arousal indices, degree of desaturation, and examination of raw PSG data
     
  • Children:
    • Enlarged tonsils and adenoids are the most common source of airway obstruction in children and result in sleep-disordered breathing
    • History and physical examination is often sufficient for diagnosis of OSA in a child
    • Overnight pulse oximetry or formal PSG is occasionally used to aid in decision making 
      • AHI >1 is considered abnormal in a child

 

Long-Term Complications of OSA:

  • Adults: Hypertension, pulmonary hypertension, cor pulmonale, atherosclerosis, ischemic cardiovascular disease, glaucoma, and decreased seizure threshold.
  • Children: ADHD-like behavioral problems, delayed growth, nocturesis

 

Clinical Examination:

  • Examination for a patient with sleep apnea is important for exploring potential surgical treatment options
    • Nose: Nasal obstruction, deviated septum, turbinate size, allergic rhinitis
    • Oral Cavity: Tongue size, tonsil size, high-arched palate, redundant soft palate, uvula or tonsillar pillars
    • Mandible: Micrognathia or retrognathia
    • Drug-induced Sleep endoscopy (DISE) may be used to evaluate the airway to refine the surgical treatment plan

 

TREATMENT

  • Lifestyle modifications: weight management and avoidance of alcohol and sedatives
  • Continuous positive airway pressure (CPAP) therapy is the gold standard treatment
  • Mandibular advancement appliances
  • Surgical Options
    • Nasal obstruction may play a role in a given patient’s sleep apnea
    • Surgery (such as septoplasty) is effective at correcting the nasal obstruction, it rarely cures OSA. Rather it tends to improve CPAP tolerance
    • Uvulopalatopharyngoplasty (UPPP) was one of the first surgical treatments developed for obstructive sleep apnea. Results are mixed as patient selection is paramount to improved clinical outcome
    • Maxillomandibular Advancement in patients that have jaw deformity as cause of OSA. Demonstrated benefit from a mandibular advancement appliance increases likelihood of improved clinical outcome.
    • Currently, there are many available nasal, nasopharyngeal, oropharyngeal procedures aimed at improving air movement, however data is lacking for many of these procedures
    • Tracheotomy: Definitive treatment for uncontrolled severe cases of sleep apnea
  • Hypoglossal nerve stimulators is a relatively new device used to stimulate tongue extrusion when apnea events are detected
  • Children: Tonsillectomy and Adenoidectomy is the mainstay treatment

 

Post-operative monitoring:

  • Children <3 years old often require careful monitoring postoperatively with intensive care admission with continuous pulse oximetry
  • Special perioperative management may be needed in cases of children with morbid obesity, craniofacial deformities, down syndrome and children with neuromuscular disorders

 

REFERENCES/ SUGGESTED READING:

  • American Academy of Otolaryngology–Head and Neck Surgery Foundation. (2011). Primary Care Otolaryngology, Chapter 18: Pediatric Otolaryngology. Third Edition. Retrieved from: www.entnet.org. 
  • Epstein LJ, Kristo D, Strollo PJ, Jr., et al. Clinical guideline for the evaluation, management and long-term care of obstructive sleep apnea in adults. J. Clin. Sleep Med. Jun 15 2009;5(3):263-276