About Sleep Apnea diagnostics (Sleep Test)
Early diagnosis of sleep apnea can prevent complications and other health risks.
Sleep study is the best way to diagnose sleep apnea. Sleep study is non-invasive, with no pain and risk. It provides an accurate, comprehensive analysis for healthcare professionals.
Clinical diagnosis is required for suspecting sleep apnea. You can choose either full sleep study polysomnogram (PSG), wireless or portable sleep study device for your sleep study at Hospital or at HOME.
Most people choose to conduct the test at home because:
- Most people would sleep better at home
- Waiting queue is long and testing time is rigid in hospital
- Flexible in testing date and time
- Full report will be provide to the healthcare professionals directly
Types of Sleep tests
Level I/II
PSG / Wireless PSGA polysomnography (PSG) is an overnight laboratory-based sleep study completed by a qualified sleep technician. The study monitors and evaluates abnormalities of your sleep and/or wakefulness and other physiologic disorders that may have an impact on your sleep quality.
During sleep test, groups of sensors will be attached to your body to measure different sleep parameters. The following data would be included in a sleep study:
- Electroencephalogram (EEG)
- Electrocardiogram (ECG)
- Electromyogram (EMG)
- Electroculogram (EOG)
- Snoring Sound
- Body Position
- Oral Nasal Flow
- Leg Movement
- Chest, Abdominal Effort
- Oxygen Saturation Level (SaO2)
Level III
Portable devicesPortable devices provide you flexibility and mobility during sleep study test.
Level III
Self-monitoring testEasy to operate and can be conducted by yourself after a simple tutorial in our service centers.
How to Interpret the Results of the Sleep Study?
Learn more about Sleep Test
What do AHI numbers mean?
The Apnea Hypopnea Index (AHI) measures the severity of sleep apnea:
Less than 5 events per hour (or an AHI below 5) is considered normal sleep, whereas an AHI greater than 30 per hour suggests you have severe sleep apnea.
An apnea occurs when you stop breathing for 10 seconds or more and also have a drop in peripheral oxygen saturation or a drop in blood oxygen.
Hypopnea is a partial loss of breath for 10 seconds or more and is as severe as apnea (also has a drop in blood oxygen).
| Level of Severity | AHI |
| Normal | Less than 5 /hour |
| Mild | 5-15 /hour |
| Moderate | 16-30 /hour |
| Severe | More than 30 /hour |
How many stages of sleep are there?
Each sleep cycle contains 4 stages – known as N1, N2, N3 and REM (Rapid Eye Movement) sleep – you move through these stages multiple times during a typical night.
Sleep apnea can cause awakenings that prevent you from reaching the deepest sleep state (N3), you will likely wake up feeling tired and want to nap throughout the day.
Depending on where you reside, a Sleep specialist will be able to detect whether the stages of your sleep are disrupted by analyzing the data provided by monitoring your brain waves via electrocardiogram, which is a part of the polysomnography exam.
What is Oxygen saturation (SpO2)?
When your breathing pauses during sleep, it means you are not getting all the oxygen you need in your bloodstream. The percentage of your body's ability to inhale and absorb oxygen into your bloodstream is measured by your oxygen saturation (SpO2).
In cases of severe sleep apnea, the oxygen level can drop very low – in severe cases, it can reach 60% or less during sleep. This means that just over half of the oxygen you need to function is being absorbed.
If the saturation drops below 90%, your body and brain are deprived of oxygen. This can lead to brain damage and serious cardiovascular problems.
What is CPAP Titration?
Based on the results of your sleep study, your medical professional or sleep specialist may recommend another study or the use of associated CPAP treatment for the purpose of performing pressure titration (cmH2O).
CPAP Titration may be recommended to ensure the proper airway pressure is set for your needs.