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A sleep study is a medical test used to determine the nature and severity of a patient's sleep disordered breathing (SDB) condition. Otherwise known as 'diagnostic sleep studies' or 'polysomnograms', sleep studies may be done in the home or by staying overnight in a specialised sleep clinic.

What is a Sleep Study?

Known as a polysomnograph, or PSG, a sleep study involves being connected to a series of monitors and recording equipment used to measure important data that will help make a diagnosis about the severity of your OSA.

The description may conjure images of wires hanging from every possible centimetre of your body and while slightly exaggerated, the PSG is designed to measure oxygen levels, airflow through the mouth and nose, movement of the chest and abdomen and activity in the heart, brain, muscles and eyes.

If you are taking a sleep study at an external sleep clinic, you will be monitored by a trained professional who stays overnight. Results will then be given to you the next morning for you to take back and discuss with your dentist or health professional to make a diagnosis.

It is entirely possible, and preferred by many, to instead request a take home sleep test if you think it might be uncomfortable or awkward to sleep in a monitored clinic. If you choose to take the sleep test home, you will be shown by the sleep technician how to set up the measurement unit before you go to sleep. You will then need to schedule a time to take the equipment back to the clinic for analysis.

Who needs a sleep study?

It is not possible for the sleep physician or medical doctor to investigate whether or not you have a sleep problem while you are awake, hence a routine office visit is not sufficient for a proper sleep diagnosis. That is why you would need to undertake an overnight sleep study, which is a powerful diagnostic tool to help doctors assess the factors that may be keeping you from getting the restful sleep you need.

If you are experiencing symptoms like persistent and loud snoring or belong to the high-risk group – for example, males over the age of 65 – you are more likely to develop a sleeping disorder.

You may wish to talk to your sleep physician or medical doctor if you have the following symptoms: Loud and persistent snoring; choking and gasping for air during sleep (usually observed by a bed partner); frequent morning headaches; lethargy and lack of concentration during the day; loss of memory; and daytime sleepiness.

The issue is even more urgent if you belong to the high-risk group: Males over the age of 65; obese, smokers; drinkers, type 2 diabetes patients.

If you know someone who frequently snores and has two or more of these conditions in either category, there is a good chance the person may be suffering from a type of sleep-disordered breathing and would require a proper diagnosis.

Sleep apnea test - Why is sleep study done?

Before you can determine the potential solutions for your snoring issues, you must find out what kind of snorer you are. A variety of devices and therapies are available that address each of the different types of snoring problems. You can identify the type of snorer you are by taking the following simple tests:
Nasal Blockage Snorer

Close your mouth, press one nostril with your finger and breathe normally. If the other nostril collapses when you inhale, try holding it open with a cotton bud stick. Now try the same test with the other nostril. If your breathing eases when you prop the other nostril open, you are most likely a nasal sleeper. The aim of this test is to assess whether or not you have stuffed sinuses.

Prolonged nasal congestion can lead to headaches as it reduces the amount of oxygen that is supplied to your lungs. Nasal congestion increases your risk for sleep apnea.
Possible Solutions for Nasal Blockage Snorers:

Nasal strips: They work by holding your nostrils open for easier breathing.
Nasal dilators: Reduces snoring by supporting the nasal cavity and preventing it from collapsing during inspiration.
Nasal sprays: Improves Obstructive Sleep Apnea by helping to unblock the nose. Taking days or weeks to work, nasal sprays do not fully control OSA and tends to be ineffective if there is a permanent nasal blockage.

Tongue Base Snorer

Stick your tongue out and hold it gently between your teeth. Try to make a snoring sound. If it sound is markedly reduced when your tongue remains in this position, you are probably a tongue base snorer. That means that your tongue may be interfering with normal airflow when you breathe during sleep, because it is resting deep in the base of your mouth.
Possible Solution for Tongue Base Snorers:

Mandibular Advancement Device (MAD): This dental appliance works by repositioning the mandible such that it keeps your tongue from obstructing your airway during sleep. The mandible is the lowest facial bone that holds the teeth in place (lower jaw).

Oral sleep devices like the SomnoDent (a type of MAS appliance) helps to treat your breathing condition by bringing your lower jaw forward during sleep. The Somnodent is customised to fit your individual teeth and mouth. Consisting of a set of splints for your upper/ lower jaws, the oral device may be titrated (fine-tuned) to ensure optimum comfort and effectiveness throughout the treatment process.

At Sound Sleeper, you can always count on having a dentist who specialises in sleep apnea to supply and fit your Mandibular Advancement Device. Our highly trained team of dental practitioners will be able to deal with any unforeseen dental problems that may occur during the treatment phases. Following the successful fitting of the appliance, all you have to do is show up for regular checks at the dentist’s office so that our clinicians can periodically adjust your device to fit better.

To locate an accredited Sound Sleeper Dentist who can help to customize an effective dental device to treat your sleep apnea, click here to begin your search.
Mouth Breather

Try to make a snoring sound with your mouth open. Close your mouth. If you find it difficult to snore with your mouth closed, you are most likely a mouth breather. That also means that you sleep with your mouth open. If that is the case, you should also experience dryness of mouth in the morning as mouth breathing causes the soft palate of the mouth to dry out. Mouth breathers may suffer from nasal congestion, hence resort to breathing through their mouth as an alternative.

Mouth breathers are at higher risk for infection. This is because the air you inhale during sleep bypasses your nose and upper sinuses and reaches your lungs without being filtered – the tiny hairs and substances in your nostrils act as a cleansing filter. Mouth breathers are also at higher risk of choking when sleeping. Due to the body’s effort to compensate for the lack of filtering, choking becomes a natural bodily reflex to expel the tiny particles and dust.
Possible Solution for Mouth Breathers:

Chin-up’ strips: These comfortable strips provide external support that prevents the mouth from falling open during sleep. Not only do they help to reduce snoring, ‘chin-up’ strips reduce dry mouth and sore throats by keeping the mouth closed at night.
Oral shield: An oral vestibular shield promotes breathing through the nose by effectively blocking the mouth. It is an affordable and convenient treatment for curbing the effects of mouth breathing including dry mouth and bad breath.
Mouth spray: This works by gently lubricating the vibration-prone areas of your throat to reduce snoring. It is directly administered to the soft palate in a fine mist.

Soft Palate Flutterer

If none of the abovementioned tests have helped to assess your breathing condition, it is possible that you are suffering from palatal flutter. That means the cause for your snoring is due to the vibration of your soft palate. Snorers who are not overweight tend to fall into this category.
Possible Solutions for Soft Palate Flutterers:

Chin-up’ strips
Mouth spray

Multifactorial Snorer

You may also fit into more than one categories, in which case more than one treatment method may be required. For example, some people suffer from both tongue base snoring and palatal flutter.
Possible Solutions for Multifactorial Snorers:

Mandibular Advancement Device (MAD)
Mouth and nasal spray
‘Chin-up’ strips
Nasal dilator
Nasal strips

Other solutions to stop snoring

The sleep study test or polysomnogram measures your body's response to sleep problems and gauges how well you sleep. For example, it detects pauses in breathing that is commonly associated with obstructive sleep apnea (OSA). In severe cases, the pauses can occur 30 times or more per hour. These studies are important because people are usually not aware of their nocturnal breathing patterns and behaviours or the risks involved with untreated sleep problems.

The most common type of sleep disorder is obstructive sleep apnea (OSA), which accounts for 52% of all apneas in Australia.1 The condition is defined as complete or partial blockage of the airways for about 10 seconds or more. OSA occurs when the tissues in the back of the upper throat collapse – in the relaxed state of sleep – and obstructs the air passage. In most cases, the person is not aware of these nocturnal episodes and may subconsciously wake up gasping or choking.

As sleep apnea typically manifests in noisy snoring, most patients see a doctor about the condition when it has negatively affected the sleep quality of their bed partners.

The untreated condition can potentially result in mild to serious medical conditions such as:

High blood pressure
Heart failure

Sleep apnea patients are also more prone to drowsy driving which increases the risk factor for motoring accidents and death. Young children with untreated sleep apnea are more likely to be hyperactive and inattentive, symptoms commonly misdiagnosed as attention-deficit hyperactivity disorder.

Lose weight
Apply medications – including steroids and/or allergy treatments
Ear, Nose, Throat (ENT) surgery
Quit Smoking
Lower or stop alcohol consumption

Preparing for a sleep study.

The polysomnogram involves a non-invasive – and generally comfortable – procedure so there is nothing to be worried about. Nonetheless, it is always a good idea to be prepared for any type of medical procedure so that there won’t be any surprises along the way.

You would be advised to keep to your normal sleep habits and routines, at least for about two to three days prior to the study. The reason for this is because the doctor is trying to assess your typical sleep patterns, and the results will not be as accurate if you are more or less rested than normal. You should refrain from taking any sedatives or consume caffeinated drinks the night before the test.

The sleep study is a pain-free procedure that is comfortable for most. It may be mildly uncomfortable for those who are not used to the small leads being attached to their bodies using creams and tape.


Sleep study procedure: What to expect from a polysomnogram

The sleep study usually takes place in what resembles a hotel room. The key is to make you feel comfortable as if you are sleeping at home, hence apart from the relatively compact monitoring equipment, you would not feel like you’re in a typical clinical environment.

The procedure involves attaching physiological monitors to your body and electrodes on your head to record your nocturnal breathing patterns as well as brain and physical activity during sleep. As such, you would want to keep yourself physically clean for the procedure. It is best that you avoid wearing any oily or sticky grooming products as they may make the experience less comfortable. A small sensor that measures blood oxygen will be placed on your finger.

What is monitored during polysomnogram?

The polysomnogram (PSG) measures the quality of your sleep using a variety of devices:

Electroencephalogram (EEG) for brainwaves
Electroculogram (EOG) for eye and chin movements
Electrocardiogram (ECG/EKG) for heart rate and rhythm

In summary, the polysomnogram records and depicts a true picture of your sleep patterns by gathering the following types of data:

Brain waves
Heart rate
Eye/ chin/ limb movements
Blood oxygen level
Breathing pattern
And others

Sleep study results & Sleep apnea diagnosis

The physician will then offer his/her professional take on the results, offering therapy in the form of medication, continuous positive airway pressure (CPAP) or oral appliance. Surgery is usually only recommended in cases when conventional treatment does not work.

Diagnosis is generally based on the following indices:
Apnea Hypopnea Index (AHI)

The diagnosis for obstructive sleep apnea is typically obtained from AHI readings that are derived from the polysomnogram. The AHI indicates the number of apneas (pauses in breathing) or hypopnoeas (shallow breathing) recorded during the study per hour of sleep. The extent and severity of OSA may be measured and classified according to the index as follows:

(AHI is expressed in number of apnea events per hour)

Zero to minimal presence: AHI less than 5
Mild: AHI more than or equal to 5, but less than or equal to 15
Moderate: AHI more than or equal to 15, but less than 30
Severe: AHI more than or equal to 30

Respiratory Disturbance Index (RDI)

In addition to calculating the events of apneas and hypopnoeas, the RDI measures other more subtle breathing irregularities as well. That is why a patient’s RDI may be higher than his or her AHI.

What is the cost of sleep studies?

At Elsternwick Sleep and Snore Clinic we offer overnight sleep studies that are bulk-billed for all Medicare patients, meaning no out-of-pocket expenses required.

Private sleep studies are also available for self-funded patients or those with private health insurance cover.

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