My Journey from BiPAP Auto to Aircurve 10 Vauto

[Croatoan]

I know we've moved a bit past the nasal pillow that covers the mouth but I'd like to put a vote in for the Philips Amara View. That's the mask I've used for a number of years. I also don't know if it helps but my father has been on CPAP therapy for over a decade but starting out he was severely claustrophobic with his full face mask. It doesn't bother him anymore but it used to really frustrate him. So for some people it is something you can train yourself to get desensitized to and used to if you do have to wear a full face mask.

[staceyburke]

Stacey, the low oxygen content is not something we want to see, and I would suggest a minimum of 88 is too low, and would defer to your cardiologist on this one.   Leaks are below the large leak threshold, and the machine should be able to compensate for that. I suspect your inspiratory effort is too weak to fully trigger IPAP when a leak is happening.  I suspect that these periods of low respiratory flow may be related to a REM sleep state which just happens to coincide with higher leaks.

Let's review where you are at in settings.  You are using Vauto 9.0 to 20.0 pressure with 4.4 PS.  I don't recall trigger sensitivity, and would like to know what O2 feed rate you are using.  I know we talked about 4.0 L/min.  I am thinking about trying a trial of VPAP S (fixed pressure) mode without Easybreathe, but I don't want to push you into that too soon.  The advantage of those settings is that you will get a much stronger and more assertive trigger to IPAP, which might result in a higher tidal volume when you have these segments of low respiratory flow.

These are the settings. I have never changed the trigger.  I am putting in the max continuous rate of 5l my machine allows. I know nothing about VPAP S!  Any suggestion will be put in tonight. I am trying to get ready for my Dr. visit in about a week and a half.  I know they have O2 concentrator that goes to 10 and want to give the Dr as much info as possible. With the hassle and cost I want to avoid another sleep study which would make my 6th.

[Sleeprider]

The only change I want for tonight is to change the Trigger Sensitivity from Medium to High. This will allow your machine to be more sensitive to when you are beginning to inhale and may improve the inspiratory pressure support for you.

[staceyburke]

Thank you for the input, I owned that mask and could not make it work. I happy you found it good for you.

[staceyburke]

Thank you, it will be changed for tonight.

[staceyburke]

My apnea is in great shape.  I am trying to get info for the lung Dr. visit next week.  I had a lot of pulse change and SpO2 drop showing up.  Is this normal?  Do I need to consult with the Dr.?   AND I have a question about hooking up the Oxygen.  I was told the correct way is to hook up the Ox to just as it exits the machine into the tube.  I'm at the max my machine can produce (5l) if I hooked it up where the mask and hose are connected I would think I would get more Ox.  Am I correct or would that throw off the pressure settings?  If that is the problem can't the auto settings take care of that?

[SarcasticDave94]

I would think that an oxygen bleed (connection) at the mask may help with the dilution amount. By enough to make a difference? Not so sure on that. Numbers otherwise are looking good.

[Sleeprider]

The location of the oxygen bleed will not change FiO2 at the mask, and it will not affect the machine's detection of pressure. Let's see if we can figure it out from the wiki.

You are using a nasal mask that at a median 11 cm bilevel pressure will flow about 35 L/min of air, with a 5-L/min oxygen bleed resulting in a total flow of 40 L/min.

FiO2=(5-L/min x 100%O2) + (35-L/min x 21% O2) = (500+735)/35 L/min = 35% oxygen at the mask in a leak-free circcuit. That is very high, but since you use 4 L/min without any dilution during the day, your non-CPAP FiO2 is probably close to 90% oxygen rather than the normal 21% the rest of us see. So with your BiPAP your FiO2 is less than during the day with a 4 L/minute nasal cannula. I am not a doctor and cannot assist on whether this is sufficient, but you can offer your doctor this estimate of your FiO2 on bilevel therapy with a 5 L/min oxygen bleed. Note if your excess mask leaks increase to 25 mL, the FiO2 drops to only 30%

You are probably aware that your room air is oxygen enriched, and you must take precautions with fire and flammables. A higher FiO2 will require a second generator. We have seen this done, but it is well beyond my experience.

[staceyburke]

Last night was again excellent with the only event 1 ca.  The reason for  the post is O2 levels.  With this night I moved the O2 supply between the hose and mask from it normal spot machine and hose.  It does look a little better - I still have periods where the O2 drops to far.  They all are accompanied by a larger leak rate.  I have been told the Flat top is a sign of mouth breathing.  The dashed line on the leak rate is "leak rate upper threshold".  The only one that is above that line is around 2:20 on the graph and that was a short duration but also the low of 82.  Question is this showing a need of a mask change to a full mask?  I am using a very minimal mask the "prong" type cushion.  I had tried a full face mask about 8 years ago and could not sleep with it.  Maybe the Resmed F30 or F30i would work.  OR is this graph looking ok and no need to change the mask?

[Gideon]

If the oxygen is ported between the mask vents and your face, and I'm not aware of a mask that does this, the Oxygen would be a higher concentration. Anywhere else and it doesn't matter.

I could jury rig a delivery system to do that for a nasal or fullface mask.