sleeptech

If you are comfortable without the humidifier don't use it. If you run the humidifier turned on without water in it no harm will be done. It will just waste electricity. I just downloaded a CPAP machine of a patient who has been running their humidifier at max with no water in it for months with no problems. It is, of course, best to turn the humidifier off if you aren't using it. Also, many CPAPs have a detachable humidifier as BigMike52 said. Which model do you have (I've used most of 'em)?

ASV is no more a ventilator than BiPAP. ASV is a sub-set of BiPAP specifically designed to treat central apnoeas (generally Cheyne-Stokes) in the setting of low CO2. This was something which conventional BiPAP was not always very good at. However, you should not be using either BiPAP or ASV unless you have conditions they were designed to treat.

Your problem with the AirFit P10 is quite a common one. I hear it a lot. The only real solution is a different mask. Currently my favorite intranasal mask is the DreamWear intranasal, although you may find the under-the-nose version worth a look. Also, the Nuance is not bad. Both the DreamWear and the Nuance have gel pads in the nasal prongs which are gentler on the nostrils than the AirFit. Most of my patients prefer them. do a bit of googling to see what they look like.

When you say your temperature drops, how are you measuring it? Those temperature thresholds you mentioned for hypothermia are for core temp, not peripheral. It is quite possible for your peripheral temp to be lower than your core temp without causing major problems.

Your Airsense 10 reports what is called "unintentional" leak. Every mask has an exhalation port where the air comes out. If it didn't then, because air is constantly being pumped in, you would blow up like a balloon and float away. It also allows exhaled CO2 to be exhausted so that you don't re-breathe it. So, no matter how well everything is working there will always be a certain level of leak. This is the "intentional" leak. Your ResMed machine takes a stab at what it thinks the intentional leak rate should be, largely based on the type of mask you tell it you have, and subtracts that from the figure it reports. So, in theory, if your mask is fitting very well then you can have a leak rate of 0. 5 L/min is till pretty good. Other CPAP machines just report total leak which will include both intentional and unintentional leak. For this reason you will find that your leak rate doesn't relate to those reported by people with different brands of machine.

The problem with the ResMed method is that the machine doesn't actually know what the intentional leak levels really is, it just approximates it. However, it can easily be incorrect if you don't use a ResMed mask, you haven't set the correct mask type in the options, you have facial hair and so on. The unintentional leak rate is still useful, but it needs to balanced with a bit of thought and experience. If your machine thinks your mask is leaking but it's quiet, you're comfortable, you're partner reports no odd noises, your AHI is good, you are sleeping well, etc, then it's probably not a big deal.

A Fitbit is not a reliable method of monitoring sleep. It certainly has no way of knowing which stage of sleep you are in.

The AHI of 5 being normal thing is a rough guide, not an absolute rule. It is possible to have an AHI < 5 and still suffer significant symptoms in terms of tiredness, low energy levels, poor memory etc. Different people are different. The usual practice is to give CPAP a try and see if that helps. However, it may also be something else that it causing your problems.

The easiest way to see what pressure is just to start it going. The DreamStation will show the pressure it's running at on the display. You may want to cover the end of the hose to stop the machine being noisy. The DreamStation doesn't records sats. You'll need a separate piece of equipment. It is possible you can but one that connects to the DreamStation, but I wouldn't bother. It'd be harder to find, way more expensive and the data would be harder to get to.

Also bear in mind that there are many intranasal masks of which the Swift FX Bella is only one. Try looking about a bit before you spend you money. I have not had a patient actually use the Bella. I know that other techs I work with have tried it before without success, but I don't know what the problem was.

I tend to agree with Wiredgeorge. Setting a BiPAP can be quite a complex operation and requires experience and knowledge. If you can, it would be wise to get in contact with a professional to help you.

The only thing the mask setting in the machine affects is the level of intentional leak the machine expects to see. It wouldn't cause anything like what the OP describes.