About Polysomnography Overnight Sleep Studies
The most thorough way to test for sleep apnea is to have an overnight stay at a sleep clinic, called polysomnography, or PSG.
The cost of such overnight stays in Canada is covered by the Medical Services Plan of your province.
The PSG measures breathing and apneas, chest movement, oxygen levels, REM, leg movement, brain activity and heart rate through about 25 external probes attached to your head, neck, chest, and legs. None of these tests require the puncturing of the skin. These measurements are monitored throughout the night.
It is matter of discussion and opinion whether all this information is essential to diagnose OSA, (Obstructive Sleep Apnea), but this extra information will help diagnose other less common breathing disorders as well as other medical conditions such as heart failure and brain disorders.
If sleep apnea is confirmed by PSG, most sleep specialists will insist on a second overnight stay, where again the probes will be attached, as well as a face mask. Varying air pressures will be applied throughout the night to determine the optimal settings for the patient.
Many possible sleep apnea sufferers do not want the inconvenience and commitment of a night away from home. There is also considerable delay in obtaining a bed in public sleep clinics, ranging from 1 to 6 months.
