In ‘obstructive sleep apnoea’, respiratory arrest is caused by so-called ‘obstructions’ or the closing of the upper airways. While you sleep, the body’s musculature, including pharyngeal muscles and soft palate, relax and the base of the tongue falls backwards, closing off the upper airways.
The brain, however, continues to send signals to our most important inhalation muscle, the diaphragm, and tells it to continue working. This gives rise to negative pressure in the airways, which causes them to narrow and then close off completely. |
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