As an exercise I compared my wife on the CPAP machine for one night with a CPAP mask and machine working normally with a night with no CPAP machine just the Oximeter. This was done to see if there was any improvement in oxygen intake with the CPAP system. It would be hard to believe there wouldn't be but by how much difference does using a CPAP machine make. After doing the exercise I can report that there was only a 1% improvement using CPAP in this case. As there were no dips in oxygen levels this single exercise indicated that the CPAP machine and all the money didn't seem to make much difference in oxygen intake. Interesting I thought. My wife has been using a CPAP machine for over 15 years. I will do the exercise again sometime but I thought it was an interesting experiment
The main way the CPAP works is in using pressure to keep the airway open to avoid obstructive apnea. So the benefits would be related to the number of obstructive apnea events that are avoided. Avoiding longer events would have more benefit than avoiding short events. A CPAP essentially ignores events less than 10 seconds.
Hi mus429 Dare I presume you are an Aussie?
This is an interesting concept considering how many discussions the forum has about Oxygen levels.
I have been refused release from nearly every hospital I have ever attended, even decades ago, due to low oxygen levels so I do wonder how relevant it really is and what is truly 'normal'.
Perhaps there is a form of stealth chronic central apnea that does not cause clear events but suppresses breathing, a faulty setting in the operating system, or maybe it is just a natural reaction to certain signals or triggers like allergies, pain or depression?
Yet another thing for Sierra to research! :P
Without doing any research, my recollection is that apnea basically is temporary closing of the airway -- kind of an on off effect while you are sleeping. Other conditions like COPD or asthma may result in flow resistance to the lungs when there is no apnea. The lungs become less efficient in moving air in and out. I suspect it may be measured by the tidal volume being reduced. That can result in low oxygen. In those cases a BiLevel machine may be more appropriate where it can deliver a much higher pressure on inhale compared to exhale to improve flow. And in the more severe cases it may be necessary to add oxygen, so the same tidal volume of air contains more oxygen.
I don't think low oxygen levels are always caused by events.
There must be forms of Hypopnea and CHS or other variants that are still central in nature but not solely caused by events or anatomical issues like pulmonary disease or airway restrictions.
I thought this was an interesting article, not because of the primary subject, but because of the broader discussion about differential diagnosis. "vocabulary of disease"