Top Topics
Mask leak does not necessarily affect AHI, but it can. If it is big enough then the pressure in you upper airway will be insufficient to keep it open. And if your leak is huge, the machine sill simply not record data because it can't tell what's going on. However, in most cases mask leak has minimal effect on AHI. We usually tell people that if it's not disturbing you then it's not a problem.
While I appreciate your confidence in my experience, I don't have nay magic solution for this problem, although it is very rare to be more tired with treatment than without over a year later. This could mean that OSA isn't the only thing making you tired. You could look at iron levels and thyroid function, both of which can be corrected without too much difficulty. We also have some patients who have narcolepsy and OSA, so you could check that out.You might notice that I don't bother talking much about idiopathic hypersomnolence because that is medical jargon for "you're sleepy and we don't know why" so it's not much of a diagnosis.
EB1979, while it's possible your setting are wrong, this is unlikely given your the AHI reported by your machine. I never use the smiley faces as a measure for leak, but go by the numbers (leak rate in L/min), however it is no surprise that you could pull your mask off and still get smiley face for leak, because I would assume this is based on the average leak level for the whole night which could still be fine, despite a minute or 2 of extreme leak. If your pressure is 6 that is very low and you really should not need to have your mask or chin strap tight enough to cause discomfort. If your nasal pillows are hurting your nose you could try a different mask. I assume you have the ResMed AirFit P10 (based on the fact that your other gear is ResMed) which is not adjustable. An adjustable mask like the Nuance may give you better results. The Brevida is a little chunkier but very gentle on the nostrils because is inflates itself to fit your nose rather than relying on pressure from the straps. Or, you could look at the DreaWear under nose mask which doesn't have the prongs to seal against your nostrils (Google a picture to see what I mean). Your Chin strap also shouldn't need to be super tight at such a low pressure. It will only stop your jaw sagging but it won't necessarily stop air puffing out between your lips. If there is a leak the machine will usually compensate by blowing more air, which can cause the phenomenon you describe of the pressure increasing to an unwieldy level. Or do you have an auto CPAP? In that case there could be something you could do with the settings to help.
Sorry I haven't been much use. It is often hard to nail the problem down without being hands on.
I can tell you that it is absolutely possible for your airway to obstruct while on your stomach. The precise mechanism which causes the airway to collapse is something which is the subject of much research because we don't really know. I know that a lot of people think about snoring as being in the nose, but in my many years of experience opening up the upper airway eliminates snoring in well over 99% of cases. In over 15 years I have seen fewer than 10 instances where people have still snored once their upper airway obstruction was eliminated, and in all of those that I can recall it was because we couldn't get the pressure high enough to fully eliminate snoring (but the snoring was still reduced). I attended a lecture by Dr Collin Sullivan (inventor of the CPAP machine) in which he theorised that snoring could possibly damage the walls of the upper airway over time and make it more likely to collapse, but I have seen no research to back this up. So, in short, there's no reason to think that snoring would cause OSA. Not everyone who snores has OSA, but most do and even in instances where someone snores but has no other signs of OSA, CPAP will still fix it.
A leak under 24 on an AirSense 10 is not too bad. The machine should cope fine. If you have an AHI of 0.6 at this level of leak it should be reliable. I've never paid any attention to the point score that the AirSense gives because it is ultimately meaningless. As a professional I want objective data which is comparable to other historical data, not some arbitrary rubbish that ResMed has made up. The leak rate in L/min (that's litres/minute in case you are wondering) is a universal standard for mask leak. ResMed machines do deduct what they think the controlled leak level should be (the air which comes out of the exhalation port) from the score you see, so it is possible, in some cases, to achieve a leak rate of zero. If you use a different brand of machine it will not do this, and even a perfectly fitting mask will still have some leak reading (because there is still air flowing out of it through the exhalation port). So one brand does not necessarily compare directly with another. If the leak level is high enough it will interfere with the machine ability to detect apnoeas and hypopnoeas.
I have used the Amara View with a number of BiPAP patients and pressures as high as any machine can generate. It generally fits as well as any mask and better than most.
If your BiPAP is not set correctly, it could hyperventilate you (make you breathe too much) and send your CO2 level too low. This can then cause central events (induced Cheyenne-Stokes respiration). I hope you had a sleep study with the BiPAP on, and when you did so you should also have had your CO2 level monitored to make sure it was OK. What are your pressures?
Sounds like you need a humidifier. Or, if you already have one, it may not be set correctly.
Actually, 100% of the air flow is to you and none is from you. All of the air you exhale is blown out of the exhalation port. So you are right, as long as your tube stays dry there is no risk of pathogens growing in it.
If you've had 2 sleep studies, they should absolutely have noticed if your oxygen was dropping, so that should not be the case. Do you get any leg (or other) twitches that you know of? These could cause such a result.
Do you use a humidifier? If you are getting condensation in the mask/tube it can make odd sounds. I have only played with one a little, but the DreamStation seems fine. It has about the simplest humidifier setup I've seen. Having said that, The latest model ResMed BiPAPs (which they call VPAPs), the AirSense range, are good too. There's little to separate them. The DreamStation also has slightly simpler controls.
When you say " make the adjustment to a bipap", what sort of adjustments are you talking about? The pressure settings should not be fiddled with.
