Do you wake feeling refreshed after a night’s sleep?
If you do not it is very likely you are the victim of poor sleep.
If you, or someone else suspects that your poor sleep may be due to sleep apnoea you should first see your doctor to arrange a polysomnography (sleep study).
A sleep study maps the architecture of your sleep giving you and your doctor a reasonably accurate picture of the quality and quantity of your sleep. Importantly the study records any apnoea or hypopnea you experienced and their duration.
An apnoea occurs when you cease breathing for 10 seconds or more. A hypopnea occurs when there is a reduction in airflow or shallow breathing which is not normal.
But even before you have a sleep study you can assess if you are sleeping poorly if any of the following symptoms occur regularly:
Of course, some of your symptoms need to be observed by someone else. However, if you sleep alone and often wake with a dry mouth and you experience some of the daytime symptoms a sleep study is highly recommended.
What changes occur to the oxygen and carbon dioxide (CO₂) levels during an apnoea?
During the onset of an apnoea, the CO₂ level in the tiny air sacs within our lungs (alveoli) has decreased due to the sleeper having exhaled an excess amount of CO₂. The CO₂ deficit in the alveoli, in turn, results in a CO₂ deficit in the arterial blood level.
Consequently, the oxygen in the blood (which has bound itself to the haemoglobin to form oxyhaemoglobin) is not released to the tissues and cells. When the baseline level of CO₂ is too low, the oxygen is not fully unloaded resulting in an oxygen deficiency in the tissue.
The apnoea occurs to prevent further loss of CO₂. Once an adequate amount of CO₂ has accumulated in the lungs and in the blood, it triggers the medulla region of our brain to activate an inhalation.
Buteyko Breathing as a remedy
Buteyko Breathing teaches us to normalize our breathing.
The symptoms of sleep apnoea are a manifestation of dysfunctional breathing. Regularly breathing large amounts of air when not exercising, especially through the mouth, and relying on the upper chest muscles to move large volumes of air in and out of our lungs is dysfunctional.
By breathing in this manner, we perpetuate an entrenched habit of over breathing or hyperventilating. If we regularly hold our breath, sigh and yawn these are also hallmarks of dysfunctional breathing.
A consequence of dysfunctional breathing is that we expel too much CO₂. This has a detrimental effect upon the balance of our blood gases and pH of bodily fluids.
Breathing and the pH of our blood are reliant on each other as breathing assists in regulating the pH of the blood and the pH of the blood regulates our breathing. It is vital to maintain a balanced pH within 7.35 – 7.45 otherwise it will become too alkaline or too acidic.
The importance of CO₂ cannot be overstated. Apart from regulating our breathing and maintaining of pH it is involved with the:
As CO₂ comprises only .04% of the air outside our lungs it is a timely reminder that CO₂ is metabolically produced within our lungs. The optimum partial pressure of CO₂ within the alveoli is 40 mmHg (or millimetres of mercury). It comprises about 5.5% of the alveolar air whereas oxygen comprises about 14%. This amount of oxygen contrasts with oxygen comprising 21% of the air outside our lungs.
Therefore, any loss or retention of CO₂ within our lungs depends upon how we breathe. Put simply if we hold our breath or reduce our inhale CO₂ pressure increases, and when more CO₂ is exhaled than is being produced, the pressure decreases.
Buteyko breathing recommends exclusive nasal breathing except where strenuous exercise warrants large amounts of air being quickly inhaled through the mouth into the lungs. Nasal breathing will ensure that a smaller amount of air is inhaled and at a lower speed so that it is humidified and cleaned before it enters the lungs.
The anti- bacterial properties found in the nose do not exist in the mouth and throat. Consequently, mouth breathers inhale large amounts of dry unfiltered and cold air into the lungs. By way of a response, excess mucus will form as a protective measure against inflammation.Significantly nasal breathing creates a pressure difference between the lungs and the atmosphere.
This difference results in an improved airflow and a greater uptake of 10-20% oxygen into the bloodstream.
Nasal breathing engages the diaphragm enabling an automatic rhythm or breathing pattern to be established. It also
ensures a greater circulation of oxygenated blood to the vital organs and not merely to the upper chest area.
Nitric oxide (NO) is produced within the paranasal cavity and not in the mouth or throat. NO has numerous benefits including its
relaxant effect in dilating blood vessels resulting in:
NO has been scientifically found to assist in releasing oxygen to the tissues.
CPAP as a remedy
If the Sleep Technologist finds that your sleep study results show that you have either moderate or severe sleep apnoea you will be recommended to be treated with the assistance of a respiratory aid which provides Continuous Positive Air Pressure (CPAP).
There are two types of sleep apnoea, namely, obstructive sleep apnoea and central sleep apnoea.
Obstructive sleep apnoea occurs where the walls of the throat (pharynx) narrow and collapse thereby preventing you from taking the next breath.
Central sleep apnoea occurs where the brain temporarily ceases to send signals to the respiratory muscles thereby preventing you from taking the next breath.
CPAP forces air (which may be humidified) into the mouth or nostrils at a regulated rate and rhythm.
Many people do not tolerate CPAP (as many as 50% of users) and it can be restrictive and claustrophobic. However, it can provide urgent relief. Many users are clearly content with it as a form of sleep treatment.
But it is only treating the symptoms of sleep apnoea in that it is forcing the airways open so that an apnoea does not occur. Unfortunately, CPAP does not resolve the problem of over breathing. In fact this condition is perpetuated during the night and the person’s dysfunctional breathing will continue during the day.
So the continual use of CPAP is effectively masking (no pun intended) the problem of over breathing without addressing the underlying cause of this type of breathing disorder.