In the respiratory section of the recording we look at the breathing effort, this is what we use to determine the type and severity of sleep apnea.

What does this entail?

There are belts that are placed around the chest and stomach and record the amount of movement that occurs when you inhale and exhale. With sleep apnea we look at respiratory events and monitor the muscle movements. The stretching that occurs creates a measurable difference and this can be used to determine the amount of effort exerted during each breath. These belts are using respiratory inductance plethysmography (RIP).

The quantity of air is determined via the nasal pieces. There is both a cannula and a plastic coated metal wire called a thermistor. The cannula is called the pressure transducer (PTAF), this measures the pressure difference between inhalation and exhalation, and can determine the amount of air. The thermistor gives us similar information by measuring the temperature difference between inhalation and exhalation. The PTAF is better suited to measuring hypopneas and the thermistor is better suited to measuring apneas.

What’s a hypopnea?

This respiratory event is defined as a drop in airflow of at least 30% for at least 10 seconds with an associated desaturation of 3 or 4 %.

What is an apnea?

This respiratory event is defined as a complete lack of airflow for at least 10 seconds and is not dependant on the saturation.

This information is what is needed in order to diagnose the type and severity of sleep apnea. The respiratory component is what is looked at in a cardiorespiratory polygraphy, sometimes also called a simple PSG.

If you think you may have a sleep disorder, or are experiencing any difficulty with getting to sleep, staying asleep, staying awake during the day, or have any other sleep related questions, feel free to contact Clinique Somnomed by clicking the link below.

We provide quick and convenient sleep testing in your home, in and around the greater Montreal area. We test patients every year for sleep disorders both common and rare.