Leaks controlled but AHI up

[Chalkie]

   

I have a new ResMed AirFit 20 mask and it seems to be doing a good job of stopping leaks, based on last might's figures.

However, as you can see the AHI is poor, around 15. IN particular, Centrals are up.

I am again struggling to understand what needs to be done here. The sleep nurse wants to put the pressures up another 2cm from their already high levels.

Any suggestions as to what to do? I assume the mask is not the issue now so what about pressures and even the machine?

This has all become so much more urgent owing to something that happened at the beginning of the year. I suffered an aortic dissection (Type B) and am lucky to be here after emergency repair surgery.

So getting my apnoea well controlled is kind of super important now.

[multicast]

I wouldn't call your leaks "controlled".

[Chalkie]

What qualifies as well controlled in terms of time over leak red line and time in large leak?

[staceyburke]

You are having a lot of positional apnea.  Positional apnea can NOT be controlled by pressure changes.  You have to find out what position you are getting into and cutting off your own airway.  Have you changed your sleep position?  Sleeping on your back?  Using more (or new) pillows?  These things can cause positional apnea by chin dropping to your sternum and cutting your airway.  Think of it of a kinked hose – nothing can get through – you have to unkink the hose…

IF you can’t make a simple change like changing to a flatter pillow helps then you will need a collar.  I have a link to collars in my signature at the bottom of the page.  It shows people who are not wearing a collar and the SAME person wearing a collar.  There is a huge difference between the two.

[Peach25]

Hi there Chalkie, I’m sorry to hear you’re having confounding issues with therapy… I used to be a sleep tech (in Au), and this is similar to outcomes I’ve seen in the past. There was no straightforward solution most of the time - usually it was a combination of things to change/try before finding a suitable outcome. 
For example, we would often leave the settings as they are for a few nights while trialling a sleep positioning device that records sleeping positions (if you google ‘sleep positioning device OSA’ for instance, there are a variety of results that hold good information about position testing and treatment in conjunction with PAP devices), and then once the sleep position was either found to be the main contributor to OSA then a change in pillow/positioning device in situ was used to reduce OSA. However having said that, if the positional device (in recoding mode to illuminate what position you’re laying in) shows that positioning isn’t the issue, then the next place we would often look was at mask fit… if a ffm is over tight with the aim of reducing leak, it can actually create higher OSA due to increased pressure on the front of the jaw which can result in narrowing of the airway - this means a higher IPAP/max pressure is required to overcome the increase in narrowing/reduction of lumen size created by overtightening the mask. 
Ok, when it comes to CA events, they’re much more a mystery…you’ve mentioned thoracic surgery…if this was open, there’s sometimes a risk of injury (temporary or permanent) to the phrenic nerve that drives the diaphragm: less diaphragm movement = less clear airway breathing while sleeping, resulting CA events. I mention this only because you’ve had thoracic surgery, and if it was open, this can be a possibility, however unlikely. Moving on, sometimes CA events would happen if there is a better response to therapy - meaning, if (with a change of settings, mask, or weight, for example) there is a better response (therapy is more efficient) the body can sometimes pause breathing as there is ‘no need’ to take a breath due to the internal gas environment being optimal - however this is not to be confused with central sleep apnoea where a person doesn’t breathe enough to sufficiently oxygenate despite having an open airway. 
Sometimes I have seen people have major surgery and their body goes through a period of adjustment which has included a temporary increase in CA events, which have stabilised over time (but I’m in no way sure this is happening in your case). I have also seen increases in pressure actually increasing CA events as the body detects less need to take a breath due to optimal gases in the blood - so sometimes, increasing pressures can be counter intuitive. 
However I’d recommend reviewing your situation with your former surgeon or your specialist now, so they can clear up any other issues they might be aware of. 
It’s difficult to find the solution, and often a step-wise process, and I wish you all the best

[Chalkie]

Stacey and Peach, thankyou very much fr taking the time to reply.

Stacey, I do actually possess an SSC - I got out of the habit of using it in hospital and have not got back into the habit since. So I will do so now.

Peach, very useful to get the benefit of your professional expertise.

I will look at the device you mention. Posture-wise, I sleep on both sides, not on my back. I turn when I cannot sleep readily. Just5 a habit. I have two plump pillows but tbh the apnea pattern was no different when I had one pillow.

Surgery-wise, there is no sign of incision on the chest so I can only assume the surgery was a keyhole. I could ask the consultant at my forthcoming follow-up.

I am not sure what to do ab9ut mask tightness. It does seem to fit well It is indeed tight but how do I loosen it without increasing leaks (which are still too high according to an above reply, although without specific data as to acceptable leaks as yet.

Anyhow, so my next steps are resuming SSC use, looking into posture and probably loosening the mask a little.

I will report back and thanks again.

[Peach25]

Hi chalkie, more than happy to help if I can
Sounds like further investigation with your specialist regarding what she/he might think occurs as typical after-effects post surgery…on the rare occasion even keyhole thoracic procedures can have some impact here and there, however there’s no real way for me to know - I kindly mention it in the instance it’s worth raising with the surgeon to find out if they’ve had other instances of the same. 
In terms of your mask leak, it appears to be what I used to call incidental; meaning it happens to blow large with the odd leak due to dislodgement of some sort every now and again (as opposed to uncontrolled leak that occurs for a longer period of time irrespective of movement). 
I found that this is bound to happen for two reasons: having two distinct pressures (IPAP and EPAP) causes a constant slight shift in the mask which makes it prone to leak, and the condition/cleanliness of the silicon cushion (especially on ffm’s) affects its ability to stay in position…if it’s worn, it doesn’t hold its lovely curved shape and thus cannot inflate like a tyre beading against a rim, and if it’s slightly oily or sweaty at higher pressures it will have constant blow-by trickling past - both of these usually result in overtightening to reduce the incidence of leak, resulting in another set of problems (previously discussed). When the mask is applied, and the flow commenced, try gently lifting the mask to fully inflate the cushion so it beads a seal with the very edge against the skin, and also I recommend using a plain dishwashing liquid with no moisturisers to clean silicone cushions daily - rinse thoroughly and air dry out of sunlight and heat to prolong the durability and longevity of it (I myself have three cushions per mask so I can always have a clean one at hand when needed). I have my mask straps just firm enough to stop major leak (incidental leak I don’t worry about at higher pressures - say, over 15cm H2O, as long as it isn’t impacting on therapeutic outcomes), but loose enough to allow the cushion to be fully inflated and flexible against the skin..like when a tyre goes around a corner, it needs to be inflated so it can flex against the road surface without deflating or losing contact. 
And I just thought to mention that some providers in Au rent the positional devices for positional assessments - maybe they also do this in the UK..? Might be worth doing this instead of purchasing…just thought I’d mention that
Looking forward to updates when ready.

[Chalkie]

Thanks again Peach... I'll try the out these suggestions 

[DaveL]

Peach25 there's fascinating information here! Chalkie you are very lucky. I've learned a lot.

The sleep techs at my DME supplier sell equipment. They dispense masks, and that's helpful. However, they don't do much more. I had no idea so much could be done.

I sleep on both sides. However, I've recovered from breaking my left shoulder and I move a lot.

So this information is so very helpful.

Thank you!
Dave
Toronto

[Peach25]

Hi there DaveL, Thank you kindly 
Incidentally, I have found over the years (not coming from a critical point of view; just an observational one) that the application of tech knowledge can be varied in the equipment user community, and there are so many little things to know as a tech, it can take some years to become aware of all those little things. Being an equipment user myself helped me greatly when it came to my own tech role (sleep studies when working night shifts and troubleshooting complex barriers to equipment use when working day shifts), and it also helped build trust when all this stuff was new (and sometimes coming fast and being a bit overwhelming) for some people.
I have since 'retired' due to changes in my health, however if there is anything I can help with, I will always do my best