What is Obstructive Sleep Apnea (OSA)?

What is Obstructive Sleep Apnea (OSA)?


 OSA is a sleep-related breathing disorder that occurs when the muscles relax and causes soft tissue in the back of the throat to collapse and block the upper airway during sleep. The condition causes breathing to be partially blocked, which known as “Hypopnea” or complete pauses, known as “Apneas” for at least 10 seconds during sleep. In for severe condition, a patient’s apnea may continue for more than one minute. As a result, it will lead to the decrease oxygen saturation below normal range. The brain send signal to the body in responds due to lack of oxygen that causes arousal from sleep which then help to restore a person’s breathing. This response will occur multiple times and causes individual to decrease quality of sleep and increase the level of daytime sleepiness. OSA patients commonly have the symptom of loud and frequent snoring, episodes of silence when the airway is block. In order to reopen their airway, they will make choking, snorting or gasping sounds. Apnea-hypopnea index (AHI) is a unit of measurement for sleep apneas to indicate the average occurrences of apneas and hypopneas in an hour during a person’s sleep.


  • Mild OSA: AHI fall between 5 – 15

People who tend to fall asleep during light activities like watching TV or reading

  • Moderate OSA: AHI fall between 15-30

People who tend to fall asleep during moderate activities like working or meetings.

  • Severe OSA: AHI occurs more than 30

People who tend to fall asleep even during activities that require them to stay alert like driving or talking.