What is Sleep Apnoea?
Sleep apnoea (sleep apnea) is a condition that affects breathing when you are sleeping due to a narrowing or total closure of the airway, this results in disturbed sleep, although you will most likely be unaware of this disturbance, it leads to symptoms such as excessive daytime sleepiness.
Your partner may hear the tell-tale signs of sleep apnoea while you sleep - snoring followed by a period of silence, and then, perhaps, a loud snort or a gasp as you resume breathing. Once recognised and diagnosed, this condition is easily treated and can transform your quality of life and improve related health issues.
There 3 types of Sleep Apnoea
- Obstructive sleep apnoea occurs when the muscles that control the upper airway relax during sleep. If they relax too much, the upper airway becomes narrow and some people begin to snore. If the airway becomes too narrow, this may cause breathing difficulties. Sometimes, the airway becomes completely blocked and the person temporarily stops breathing, experiencing an "obstructive apnoea." This can last for ten seconds or more. It may happen frequently-even several hundred times a night
- Central sleep apnoea is different, as the airway remains open, but a person's respiratory drive has been affected in some way, and no effort is made to breath for a period of time
- Complex sleep apnoea is a combination of obstructive and central events during sleep
Obstructive Sleep Apnoea is the most common of these.
What happens in people with Obstructive Sleep Apnea?
The soft tissue at the back of the throat relaxes during sleep, lack of muscle tone and gravity then cause the airway to narrow resulting in vibration to cause snoring. If the airway continues to collapse an obstruction follows causing an apnoea.
Partial closure of the airway results in decreased airflow and shallow breathing, this is often referred to as a hypopnoea.
When the airway is totally closed, breathing stops. The person will wake up enough to regain control of the upper airway, breathe again, and then fall back to sleep. These episodes will be in excess of 10 seconds each. This happens from a few to hundreds of times per night for people with obstructive sleep apnea, but they usually don't remember waking.
- Each obstruction deprives the body of oxygen and forces it to retain carbon dioxide that it would normally breathe out
- As a result, the body's blood gases get out of balance, and the body is subjected to a 'toxic' environment
- When the body sets off 'alarms' that it needs more oxygen, the brain wakes the sleeper, breathing resumes, and the individual falls back to sleep until the next obstruction occurs
- These obstructions increase heart rate, raise blood pressure, and eventually blunt the body's automatic response system, resulting in increasingly more severe apnoeas and hypopnoea
- Continued disturbance to sleep diminish the quality of sleep, resulting in sleep deprivation
The number of Apnoeas and Hypopnoeas experienced determine the severity of the disorder (Apnoea Hypopnoea Index - AHI).