I can't get to grips with my Mask Leakage!! or Can I?

[DevonBound]

Ur Hum!

Almost Sorry to interupt you chaps.....

TF .....I am now becoming increasingly concenred about my AHI level, I now have my base at 15.5 & Upper at 18...my 90% cm2 is now reading 17.6 and leakage rate seems stable at 43lpm, so no higher than usual....but my AHI is creeping ever skyward now at 14.6......I am becoming very confused, I seem to be getting a good nights sleep - well lets just say I don't wake up very much, but now when I wake in the morning I feel shattered again and found my weekends once again waking around normal time, taking off the mask and lying in for a few extra hours cos I'm so tired.

The lowest I have had my AHI is 10.....? I have slowly and systematically cranked up the Pressures to where they are now and yet my events see to be on the increase...confusing!

I don't drink so this is not a factor, have found myself on my side a lot - so the lying supine doesn't seem to be the issue either...and I remain adamant that this mask isn't leaking anymore than it should...any advice you might have now,given that all theories would suggest that I can't get anymore from this treatment?

[Floatyboaty]

Interesting, DB, I found that I too was returning to tiredness this week and on Friday discovered an American website which told me how to unlock the clinicians menu on my cpap. (I may be shot now!)
I increased the upper pressure and for two nights had an excellent sleep. cpap as you know does not record ahi (what does that stand for?) so I have no idea how many episodes I now have. Pre cpap it was 90 per hour.
I have a feeling that there may not be a 'set' pressure that suits us all the time but that there is a need to adjust when the tiredness returns, a bit like TF and his cpap/apap experiments. I discovered very early on that the ramp did not work for me I was not getting enough air, so now I never use it, just going straight into full rush. What are your thoughts on maybe there is no 'set' settings??

[Tigers Fan]

Clinic time

Hi DB

Les has a theory about going beyond our optimum pressure - so maybe dropping a point or two would help you. I'd definately drop your max to 17.5 or whatever lowest you can get, closest to 2 cm above your base pressure.

However, what I am hearing loudest of all is that you need to return to your Sleep Clinic so they can see if there is anything besides OSA going on. Maybe you need BiPAP or a tonsilectomy or ............

In the meantime, not to worry about AHI 14.6 - you survived much worse before you were diagnosed, after all. It's a pain in the rectum but that's all, except, with reference to another thread, you need to be careful.

Back to the Clinic, fast as you can, is my advice.

Tigers Fan

[leswaller]

Yep, I definitely found that if I cranked the pressure up above what I consider to be optimum my AHI goes up again. Try adjusting the pressure down until you get to a low point on the AHI, but before it starts going up gain because the pressure is too low

[DevonBound]

Nope - Not getting any better!

Hi All,

I have been tweaking my settings and mask fit now for a good few weeks since my last posting and nothing seems to make any difference.

My AHI reading simply will not budge below 9.5AHI.....it really doesn't matter what I do - it will not shift. I am though very patient and tend to wait 3-4 days before making another adjustment....I have tried lowering my pressure settings really quite low and going through all the gears up to current level....but regardless of what the setting is at, my 90% is always in 17-18 range.

Strange thing is, I sleep fantastically well and generally feel quite good - I feel great at work very alert, don't fall asleep at weekends and am even now working on my weight by doing 10mins every morning before showering on my Cross Trainer...so generally feel much better.
I sleep right through of a night without waking and my wife tells me that I definitely do not snore or stop breathing anymore....so why is my AHI @ 10+?

I have been reading about Central Sleep Apnoea? where basically the brain allows us to breathe so shallow, that we practically stop breathing - nothing to do with the throat collapsing at all just the wrong brain signals lowering the breathing....and have to say I think I have many of the symptoms. I often have to catch my breath in the day because it is as though I have forgotten to breathe and generally breathe very shallow when dropping off to sleep...has any one else any knowledge of this personally or professionally? could this be the reason why my AHI is not lowering further - although I have stopped snoring and my throat is wide open, my brain is allowing my breathing to almost stop regardless of pressure settings?? is my understanding of this correct?

My pressure settings are now at 16.5 + 18.5, sleep very well, do not wake up and am still adjusting these figures upwards every 3 - 4 days just to see if there is a change in events....but as yet it seems not to matter what I adjust, the AHI doesn't move?

Leswaller & TF - I have tried your method of lowring the pressure settings and in fact started from scratch and went back through the gears from 4 - 20 up to present situation of 16.5 - 18.5.

Mask Leak rate I mentioned once before is stable around 44lpm and the mask fits well with no obvious leaks in the night.

Any suggestions my friends - most appreciated as ever?
Thanks DB

[James @ Intus]

Couple of thoughts on this.

First off, I think it would be better to make changes after 7 days, so you can take the AHI readings over a 7 day period, rather than relying on last night's reports. Many things can change night on night and as per my other thread, there are indications even something as 'trivial' as the weather can affect things. So to get more reliable readings, perhaps try and stick with 7 day reports.

Secondly, "seeing is believing". You partner may not be witnessing any events anymore but surely, she also sleeps during the night at some stage. If you have a video camera, or can borrow one, put it on a tripod and point it at your head in night mode. Check in the day to see what's going on.

In central sleep apnoea you don't get the chest shocking motions so maybe you can hear the machine ramp up without any visual signs of an event.

If you really want to check what's going on, you can also consider a multi-channel respiratory sleep study at home, perhaps two nights, one with CPAP (to confirm the machine's AHI readings) and one without. With the chest effort sensors and airflow recordings, they can differentiate obstructive from central events.

A third idea is to not worry about it for say 2 months. You say you sleep great, feel great and even exercise now. From that perspective, you are doing infinitely better than before CPAP. The mask and machine don't appear to be bothering you so maybe a "let's stop being fixated for a while" approach may somehow settle things. Accept it's going swimmingly by most standards and re-check in a month or two.

Lastly, I didn't catch which actual machine you have but there are APAPs which specifically have algorithms to differentiate obstructive from central events and react differently to them. You may want to check your machine can do this.

[leswaller]

Hi Devonbound

Just a couple of points, you say your leakage is stable at 44lpm, that seems very high to me, I am running at an average of 0.2lpm (after a lot of strap tweaking) and I wonder if this might be affecting things.

Having tried TFs plan of just having a 2 cm difference in pressures I must say that I am not convinced for myself. I understand the theory that by raising the base pressure the machine can react more quickly to any aponea events but this really only turns an APAP back into a CPAP with a pressure bandwith rather than a fixed pressure. The side effects of more noise, more ambient pressure and a higher leakage rate didnt seem to give me any perceived improvement. However it must work for TF, who being an engineer, will have gone into this course of action based on his own calculated experiences.

I have gone back to having the bottom pressure at 4 and I have set the max pressure at 2 above the highest pressure I have ever needed (14.4 + 2 = 16.4) on the basis that it doesnt need to go any higher than that, and cant blow me out of bed.

I have subsequently managed to get hold of the clinical software for my machine and have been comparing the output graphs for using the machine with my settings against using it the way that TFs uses his machine. These results, for my condition (may be different for other people) seem to indicate the following
1. My AHI is not affected by raising the base pressure or reducing the max pressure or alternatively by restricting the machine to a narrow band of pressures.
2. Leakage rates are reduced noticably by lowering the base pressure.

My usual nightly AHI is around 5.3 and on average is made up of 5.1 HI and 0.2 AI.

James perhaps you could comment on these numbers please, I know what they mean but am interested to know if this ratio is good bad or indifferent

[James @ Intus]

You raise a good point there Les, splitting AHI into Apnoeas and Hypopnoeas. It would be interesting to know DB's split on this because if his 10-ish events are 9 Apnoea's and 1 Hypopnoea's that would be far more critical than the other way around.

Also, it depends on the machine's definition of an apnoea and a hypopnoea event. On the SleepCube you can redefine it for example. The default is that an apnoea is a drop in respiratory flow down to 10% of its usual flow over a 10 second period.

A hypopnoea is a 50% drop over 10 seconds.

If your machine is set up differently, the stats will be different too of course.

Perhaps breathing resistance training hepls too, with products like this.

As far as which settings to use, each person is of course different, with different breathing patterns. In principle, I would lean towards Les's approach as for example early in the night, people tend to have fewer respiratory events. You may not need the high pressure yet so if a low pressure is more comfortable, that may suit better. But if you're not fussed jumping straight in at 16, then why not?

I guess you can expect the machine to be more proactive at higher pressures and more reactive at lower ones.

Of course, if you get stuck without further improvements, do consult your sleep physician about the situation.

[DevonBound]

Thanks James,
I understand your 'less fixated' approach for a while, but I am concerned by my worsening memory loss, while my general well being is improving, one thing getting worse is my memory and possibly my intellect - which is purely self observational and not scientific, it could just be me being over conscious of the problem and over analysing this issue?

I will most certainly mention it to the lab tech when I go back, but I am concerned that they will not be as interested in the stats as I am...last time I went they were only interested in whether I was compliant or not (hour many hours I was using the machine for) they never went through the stats at all apart from the leakage figures.

My machine is an APAP Resmed M Series with A Flex.....never seen an entrance to be able to extract data which separates Apnoea's from Hypopnea's....is their one for my machine?

I tried switching my pressures back to 4 + 20 last night and woke up this morning very tired and slept until 10am...after taking the mask off at 8am.

DB

[DevonBound]

James, Having read through Les's stats again....As I understand it Hypopnoea's are potentially more serious than Apnoea's....as the long term damages Hypop's can cause - I guess can be very serious....?

Would you expect from the AHI Index for the HI to be higher than the AI?

Les, James, Fully understand lowering the pressures and will persevere for a while at the default setting of 4 + 20....I have also tweaked with my mask and straps for many months (Full Face Mirage Quattro - I'm a mouth breather) and the looser I make my straps the LPM gets higher...I now have my mask nailed to my face; but comfortable, and is the only position that maintains a stable LPM at 44lpm....this is high as the sleep tech commented, but I just cannot get this any lower...not sure what to try next to be honest?

Cheers DB

[leswaller]

Devonbound
Sorry, but you have got it the wrong way round. Potentially AIs are more dangerous than HIs.
There is definitely something wrong somewhere if you are getting leakage readings as high as 44, as I previously said mine are down around the 0.2 level and I also use a Quattro mask, I also sleep on my face so the mask is constantly being pushed about. I am convinced your high leakage rate is affecting your therapy, if you had a bad night after lowering the base pressure this could well be due to the fact that your high leakage rate is causing a very slow mask pressure rise when the machine detects an event.
In order to analize the data from Resmed machines into AHI, AI and HI, you will need the clinical software which is called ResScan. The version you will need depends on the age of the machine you have. If you only have a data card outlet then it might be a bit expensive as you have to buy a dedicated card reader with the software, and as ResMed in the UK wont sell it to you, the only way is to buy from America or Australia over the internet. However if you have a machine that also has a serial port on it then if you send me a PM I will let you have a copy of the software. You will also need a 'null modem' cable which is available from your local Maplins or similar for £10 and you will need to have a serial port on your PC (some newer ones dont have one)

[DevonBound]

Then I am well and Truly Buggered!!

Hi Les,
I simply cannot fathom this leakage out.....I am adamant that this mask is not leaking from the seals or elsewhere, I know that I sleep very well but I do wake occasionally in the night and I would know if the mask was leaking...I just don't get how this rate is ever going to lower??
I note on other threads that Grumpybiker gets similar leakage rates yet his therapy figures suggest he is doing very well from it..Could it just be that perhaps I need to try another mask??
When my sleep tech saw my leakage figures a few months ago, she commented that the leakage rate was far too high and adjusted the mask for me...but when I slept that night the mask was leaking out of all sides and into my eyes....it seems that unless the mask is nailed to my face it will leak...
I am well and truly puzzled by the whole affair, but recognise that this needs resolving quickly if I am to receive the therapy you are all receiving....I will simply need to get myself to the drop in centre at some point.
DB

[leswaller]

OK, lets try and bottom this.

1. How old is your machine - was it new when you got it
2. Have you checked for leaks round the connection for the hose at the machine end.
3. Have you checked your hose for leaks - take the mask off, leave the hose connected to the machine, put your hand over the end of the hose, coil the hose in a bowl of water switch on and look for bubbles.
4. Is it possible that, like me, you are sleeping on your face at some point during the night which is dislodging the mask but not waking you. Then when you move again the mask is resealing.

The leakage rate shown in the stats is not a constant but in simple terms an average. It is therefore quite possible that some points during the night hypothetically the leakage is 0.1 and at other times 99. Regretfully the only way to see what is really happening is to look at the detailed data

[threewheelweave]

Try Something Else Idea?

Hi Devonbound

If you are not succeeding with the Quattro have you thought of trying the Liberty? I too am a mouth breather and have found it much easier to get on with the Liberty. (Cost £119 instead of the data reader etc)

If you look back at the posts on this thread one area you may want to check with Les on is the semi blocking of the Quattro vent area.

Hi Les

Les any chance you could take a photograph of how you modified it with superglue and plastic strip so devonbound can understand what you did?
They say a picture is worth a thousand words and it could be the answer as the vent on the Quattro nose bridge seems to vent more air than the two vents on the Liberty FF mask.

Hi Members
Anyone else modified their masks? We could start a new thread - what do you think Les? (instead of highjacking this specific one )

Cheers -

TWW
UK

[leswaller]

sorry can't do photos, but it is very simple. Cut a piece of scotchbrite (the green mesh stuff used for cleaning pans) to the shape of the vent, apply superglue round the edges only (so you dont block the green stuff) stick it over the vent. It works very effectively as a silencer using the same principles as a car silencer, i.e. the air flow is diffused through the mesh rather than blasting out like jets through the vent holes. ResMed wouldn't endorse it when I asked (for obvious reasons) but did go so far off the record as to say that it is important that the vent is not blocked or restricted but otherwise shouldn't be a problem. This solution does NOT block or restrict the airflow