Learn about Sleep Apnea

What is Sleep Apnea?

Sleep disorders such as insomnia, nocturia and bruxism are common among people nowadays. Sleep apnea is one of sleep disorders characterized by pauses in breathing or period of shallow breathing during sleeping. Each time of breath pause can persist from a few seconds to a few minutes. Patients may have hypoxia and sleep quality beomes poor.

Common Signs and Symptoms of Sleep Apnea are:

  • Snoring
  • Nap during reading, conference and watching television
  • Pause in breathing during sleeping
  • Breath with mouth during sleeping
  • Headache in the morning
  • Fatigue, dozing off, difficulty in concentration
  • Emotional problem
  • Decreased memory
  • Sexual dysfunction


Classification of Sleep Apnea

Obstructive sleep apnea

Obstructive sleep apnea may be caused by blockage in airway by excessive subcutaneous tissues or enlarged tonsils.


Central sleep apnea

The airway is not blocked but the brain fails to signal lungs and muscles of respiration due to instability in the respiratory control center. This problem is more common in patients with stroke or brain injury. This can lead to intermittent apnea.


Mixed sleep apnea

Patients suffer from both obstructive sleep apnea and central sleep apnea.


High Risk Factors

  1. Being over age 40
  2. Being male
  3. Being overweight
  4. Having large tonsils, large tongue, or a small jaw bone
  5. Having large neck size (17 inches or above in men and 16 inches or above in women)
  6. Smoking
  7. Drinking alcohol
  8. Use of hypnotics
  9. Gastroesophageal reflux, or GERD
  10. Having a family history of sleep apnea


Health Problems Associated with Sleep Apnea

  1. Hypertension
  2. Stroke
  3. Heart failure
  4. Heart disease
  5. Fatigue-relate traffic accidents


Apnea Hypopnea Index(AHI)

Severity of sleep apnea is determined by Apnea Hypopnea Index(AHI)(= number of apnea and hypopnea per hour).

None/Minimal: AHI < 5 per hour

Mild: AHI ≥ 5, but < 15 per hour

Moderate: AHI ≥ 15, but < 30 per hour

Severe: AHI ≥ 30 per hour



If you have doubt, please consult doctor.  The preliminary screening includes doctor consultation and nasoendoscopy in addition to home sleep test (PSG) and sleep endoscopy to understand the severity of sleep apnea and the location and constriction of blocked airway that allow doctor to tailor treatment plans or surgeries.


Common examinations for sleep apnea involve sleep study, flexible laryngoscopy & Müllers’ maneuver and sleep endoscopy.


Sleep study is highly effective in diagnosing sleep apnea. It is a test using electronic devices to record physical activities during sleep. It is a risk-free, painless, non-invasive and accurate sleep analysis. Apart from doing sleep study in hospital, people now can choose doing sleep study at home.


Parameters measured in sleep study include:

  1. Brain Waves (EEG)
  2. Heart Rates and Rhythms(ECG)
  3. Blood Oxygen Levels
  4. Breathing Rates and Patterns
  5. Apnea-Hypopnea Index
  6. Eye Movements
  7. Snoring and Noises Made While Sleeping
  8. Body Positioning
  9. Leg Movements 
  10. Unusual Movements or Behaviours
  11. Sleep Stages


Müllers’ maneuver is a procedure needs to create a negative pressure in upper respiratory tract and insert a flexible laryngoscope to investigate any blockage of airway.


Sleep endoscopy is performed with insertion of an endoscope through the nose to assess the severity of structural obstruction or narrowing of the upper airway with patients under sedation.




Inflammation can make uvula enlarged. The enlarged tissues will obstruct the airway. Influence on breathing and snoring will be more serious when people lie down to sleep since uvula will fall down to airway. Therefore, doctor will suggest uvulopalatopharyngoplasty to treat obstructive sleep apnea caused by enlarged ovula and relieve condition of snoring. This surgical procedure is used to remove tissue and/or remodel tissue in the throat. It involves removal or remodeling of the posterior surface of the soft palate and the uvula. The uvula is then folded to the soft palate and sutured together. The procedure can enlarge airway and resume breathing of patient, resulting in improved sleep quality.

Radiofrequency tongue base reduction

This is minimally invasive surgery is to treat obstructive sleep apnea caused by enlarged tongue base. The enlarged tongue base may occupy larynx and disturb breathing.The surgery uses radiofrequency to produce heat energy which heats enlarged tongue base. Protein in tongue base is destroyed and mass of tongue base reduces, resulting in improved patency of airway. This procedure is relatively safe. 


Other treatment options

  1. Sleep Devices
  2. Oral Appliance
  3. Positional therapy
  4. Modification of lifestyle such as weight reduction and smoke and alcohol cessation
  5. Avoid drinking alcohol before sleeping