Obstructive Sleep Apnoea (OSA) is a sleep disorder in which you have irregular breathing at night, characterised by repeated collapse of the upper airways during sleep, causing breathing to stop. The brain automatically reacts by waking you up to restart breathing.
What happens during sleep apnoea?
When breathing stops (known as apnoea), the levels of oxygen in the blood begin to drop. After a few seconds the lack of oxygen causes a reflex response. This forces open the airways causing you to produce a loud snort, a series of gasping breaths and often loud snoring. Sometimes, during this period of ‘arousal’, there may also be kicking and flailing of the arms and legs.
You may be totally unaware of your symptoms and, unless you sleep alone, your sleep partner may also end up with a disturbed night’s sleep.
What causes the airway to collapse during sleep?
Several factors can cause the airway to collapse. For example:
- Extra tissue in the back of the throat, such as large tonsils or large uvula
- A decrease in the tone of the muscles holding the airway open
- A blocked nose