Sleep apnoea (also spelled apnea) is a condition that belongs to a family of sleep disorders called sleep disordered breathing. Sleep apnoea can further be subdivided into Obstructive Sleep Apnoea, Central Sleep Apnoea,Mixed Sleep Apnoea and Complex Sleep Apnoea. Apnea is defined as a period in which a person stops breathing for 10 seconds or more. Obstructive Sleep Apnoea is caused by an obstruction in the airway.
During this period there is a dramatic decrease of oxygen levels in the blood. This causes the body to secrete adrenalin which temporarily raises the heart rate and blood pressure to compensate for the low oxygen levels. This is a rescue reflex but unfortunately leads to fragmented sleep architecture which results in a lack of deep sleep.