Obstructive Sleep Apnoea
Obstructive sleep apnoea (OSA) is a common disorder characterized by repetitive episodes of nocturnal breathing cessation due to upper airway collapse. OSA causes severe symptoms, such as excessive daytime somnolence, and is associated with a significant cardiovascular morbidity and mortality.
Snoring is a sound generated from upper airway obstruction during sleep. This is involuntary and can be due to obstruction from the nasal passages or oral passages. Up to 40% of
individuals snore. Some of these patients who snore may have associated serious medical conditions like obstructive sleep apnoea.
Obstructive Sleep apnoea is a condition whereby there is obstruction in the upper airway during sleep. As the body loses tone and partial control of the upper airway especially during the deeper stages of sleep, this leads to obstruction. The body’s oxygen level will start to drop and
subsequently the body will wake the individual up to a lighter stage of sleep. During this time the patient may not be awake, thus these are known as micro-awakenings. This can happen several times per hour of sleep and lead to disrupted and poor quality sleep. The patient can
feel tired and not well rested even after 8 hours of sleep.
The patient can also experience the following symptoms of sleep apnoea:
- Choking during sleep
- Daytime somnolence
- Falling asleep easily in the day
- Compensating fatigue with coffee intake
Associated medical conditions of sleep apnoea includes:
- Cardiac disease/ arrhythmias
- Fatty liver
- Increased chance of road traffic accidents
- Sudden death
Obstructive sleep apnoea occurs from obstruction. This can be from either the nasal passages
or oral passages.
1. Nasal Passages
- Deviated nasal septum
- Inferior turbinate hypertrophy
- Adenoid hypertrophy (usually in kids)
1. OralL Passages
- Large tongue
- Large soft palate
Sleep apnoea is usually diagnosed with a sleep test. In the past we used to perform it in a sleep
laboratory with one night admission in the hospital. The patient will have multiple leads attached
to the forehead, face and chest area. One problem was the issue of “first-night” effect. This
happens when the patient is unable to fall asleep normally during the sleep test.
Sleep apnoea only occurs only during sleeping. There will be no obstructions whilst the patient
is awake. So it is important that you can fall asleep normally during the sleep test itself.
Otherwise you may have to repeat the sleep test.
Another simpler way to do the sleep test would be to use the WATCHPAT. This can even be performed in the comfort of your own home or hotel and all we need is 4 hours of sleep time for accurate interpretation of the test results.
Picture of a patient with a WATCHPAT undergoing the sleep test
Depending on the severity, if you have moderate or severe sleep apnoea, it can lead to serious
CPAP: Continuous positive airway pressure. CPAP is an effective treatment for moderate to severe obstructive sleep apnea.
Patients with obstructive sleep apnea treated with CPAP wear a face mask during sleep which is connected to a pump (CPAP machine) that forces air into the nasal passages at pressures high enough to overcome obstructions in the airway and stimulate normal breathing. The airway pressure delivered into the upper airway is continuous during both inspiration and expiration.
Nasal CPAP is currently the preferred treatment for moderate to severe obstructive sleep apnea. CPAP is safe and effective, even in children. Daytime sleepiness improves or resolves. Heart function and hypertension also improve. And, importantly, the quality of life improves.
If you are unable to use CPAP, it is important to find out the reason before surgery. Sometimes
chronic rhinitis or nasal congestion can make it challenging to use CPAP. In this case, it is
important to pre-treat the nose to relieve the nasal congestion before doing CPAP therapy.
If a patient is really unable to use CPAP, surgery is an option that can help treat this condition.
Surgery is targeted at treating the areas of obstruction. For example, if a patient has large
tonsils, tonsillectomy can help treat this condition. If there are nasal causes of obstruction, a
septoplasty or turbinate reduction surgery can help treat the sleep apnoea too. The type of
surgery performed will be tailored to the individual patient and his site of obstruction so it can be
variable. Thankfully with the latest technologies, surgeries can now be performed in a minimally
invasive manner in a relatively painless manner.
Click here for Dr Dennis Chua article published in Business Times 2016 on Tackling Obstructing
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Feel free to drop us a message if you have concerns or symptoms pertaining to sleep apnoea.