Being recommended for Bipap: 1 year out from Craniotomy

OK, there is quite a bit going on there. A couple of OSCAR tips. If you click on the black triangle beside the current date you can hide the full month calendar which lets more of the details on the left panel show. And, at the bottom of the left panel there will be a list of the sessions in the night. Beside each one is an on off switch that turns red or green. I use that switch to suppress garbage sessions like the mask testing you were doing at 21:00. This lets the rest of the night show in more detail.

Out of this the session from 1:10 to 5:20 when you were on your side looks pretty good, and 13 cm seems to be enough pressure. However the session in the recliner on your back was not so good. Looks like that position will need a lot more pressure.

I think I would leave the minimum at 13 cm for now and let things settle out a bit before trying more changes. The Standard response is bringing pressure up quicker to control events which is good. If there is a pressure that you do not want to go above for comfort reasons then you may want to lower the maximum pressure to what you can tolerate. It may cost you with a higher AHI especially when you sleep on your back. I have a maximum set on my wife's machine set for that reason. Flow limitations would drive the pressure higher than she likes if there was no maximum to limit it. Her long term average for AHI is 0.48 so this seems to be an acceptable compromise for her.

Overall that looks pretty good. Even your respiratory rate is normal. It appears the pressure increases are being driven by the Flow Limitations and almost all OA events are being avoided. I don't think there is any reason to further adjust the readings at this point. I would just watch the results for a few nights to see if anything different happens.

When I was trying different masks I would test them during the day with an attempted nap so there was no worry about getting a sleep. But that is easy for me as I am retired... Mask testing and adjusting is difficult. I started with the AirFit P10, then to a AirFit F20, Mirage FX, Brevida, Mirage Quattro, Swift FX, and finally back to the P10 with Swift FX headgear adapted to work with it. Over that time I tried several different chin straps, and started mouth taping... It was a long journey!

All in all not a bad outcome. With what was going on your machine setup is probably pretty close to optimum. I think the 1:00 event was likely the mask coming right off your nose. With SmartStart on the machine would have shut down on high flow as it is supposed to. When it started again you were back in the Auto Ramp mode which is as it should be.

That period of time from 5:45 to about 5:55 is interesting. That is about as low a leakage as I have seen for your results. That looks close to normal, but didn't last for some reason.

On masks the financial impact was not that bad. I got the P10 as part of the initial package at not much extra cost. The Mirage FX was borrowed from my wife. The Mirage Quattro was a spare I borrowed from my son. The Brevida I "sold" to my wife when she got tired of the Mirage FX. The Swift FX has gone nearly unused except for the headgear I salvaged from it. The purge vents on the Swift were like a jet engine taking off for noise and velocity. I just could not sleep with that high velocity air flow, but the rest of the mask was great. And the AirFit F20 has been pretty much a total write off. I just could not make that mask seal, and when it leaked it would blow straight into my eyes. At the time I was in Auto mode and was using more in the range of 15 cm of pressure. Perhaps now that I'm at a fixed 11 cm it may work better. I keep it as a spare.

On your nose irritation from the F20 you may want to try some OTC 1% corticosteroid cream. Put it on in the morning to promote healing. It should not be used for more than a week or so though. Another possible solution are RemZzzs Mask Liners. Some report success with them, and even make their own with t-shirt material to save on the cost. I did not try them when struggling with the F20 I have.

Looks very good. Flow Limitations are driving the pressure increase. If you think that is going to wake you up, then you could limit that rise with a lower max pressure setting.

Your leak rate chart does not suggest you are opening your mouth. Normally those events will be sudden and have a flat top somewhat above the leak redline. If anything, some of these events appear to be related to waking up and could be just sleep wake junk. If you are not comfortable with a mask then the chances of waking up are greater. It is possible you are more comfortable with the F20 and that is the reason it is giving better AHI numbers.

I have had a look for a source of replacement seals on the machine, without any luck. Here is a link to a company that sells second hand as well as new machines. If you called them, they perhaps would be able to suggest where to get parts. I could not find the exact seals on a search there. Your leak rate chart is sure showing there is a fixed leak.

https://www.secondwindcpap.com/

In any case despite the higher readings on this night, I think the machine is getting close to the best you are going to get out of it. You could try going lower in minimum pressure, but that might not bring any improvement. OA events could start sooner, and the pressure would go up anyway.

Here is a video showing the seals inside the machine. The part on the right along with the seal is removeable and you can buy it on line for $10 or so. The one on the left if that is the issue, is more difficult. This video is suggesting you clean it, as the dark spots may be mold. Might be worth a try. There are other videos that show how to tear the whole machine down, but if you can't get the replacement seal then that is still a problem...

https://www.youtube.com/watch?v=3O7tzeLDHj4

Well, you have kind of a Dr Jekyll and Mr Hyde behaviour in your apnea outcomes. With the collar and sleeping on your side it looks like 13 cm is fine, but when you get into the more difficult position it seems that 20 cm is almost not enough. My thoughts are that you should do just fine with a standard APAP if the position is controlled. And the other consideration is that running up to 20+ for pressure is not going to be the most comfortable and the easiest for a mask to deal with. And, higher pressure may drive up your central apnea event frequency.

I guess one thing to consider is that a VAuto BiPAP can be set up to replicate what you are getting for treatment now with the APAP. If you are paying for the machine, I would not consider it, but if they are giving you the machine there is probably not much of a downside. I have not looked at the VAuto for some time, but it might be missing a feature or two compared to the latest AirSense machines. For example I am not sure it has the auto ramp feature, but that is more of a nice to have, than a must have.

It is hard to say if raising EPR above 3 would help much. You certainly do have periods of more flow restriction where it may help. I think overall your results have improved by having EPR at 3 cm, but it is hard to predict if more would be of benefit. If you were to get a VAuto I would suggest that you set it up to replicate what you have now. Then you could experiment to see if more pressure support is of value or not.

The CA events are unlikely to be caused by body position in my thinking. They are when you simply stop breathing and there is no flow restriction. For many they can be caused by the pressure. Higher pressure tends to cause more central events. However, on this night your CA events seem unrelated to pressure. You went up to 18 cm and there were no CA events associated with that pressure rise. The CA events just before waking up often tend to be because you are waking up and going back to sleep. If you zoom right in on the two events at 4:10 and 4:40 you might learn something. The flow graph would be the one of interest. In my issues with CA what I often find is a minor OA event that is not long enough to be flagged will start to cause my breathing rate to be unstable, and eventually end up with a CA event. It is worth looking at what led up to the CA event to see what may be the cause. If you post a zoom in of each of those events I can give you my thoughts. They need to be zoomed in to the point where you can see each individual breathe in detail. It is the period of time leading up to the CA event that is most important to look at.

Your pressure increases seem to be in response to flow limitations. Those may be caused by body position. I think I mentioned before that some go as far as sewing a tennis ball into the back of their PJ's to encourage sleeping on one side or the other but not on their back.

In the scheme of things, there is not much you can do with central events, and your incidence is not that high. Limiting pressure can help, but your events do not seem to be caused by pressure. BiPAP machines have some limited ability to deal with central events. However, when central events are a much more serious issue the best machine are the ASV types. In range of cost, an APAP is about $1,000, the BiPAP about $2,000, and an ASV about $5,000. With your current numbers I see no reason that you would need more than an APAP.

On that first event at about 4:10 I think just before the CA event you had a short OA event that did not last long enough to be flagged. When the machine determines that flow has stopped it starts a high frequency flow cycle. This is how it determines whether the event is a central or obstructive type. If it is obstructive then the pressure cycles up and down in response because the airway is blocked. If the pressure does not cycle up and down as much then it means the airway is open. In the 4:10 event by my eye the short period of cycling produces more of a pressure response than later when it gets flagged as a CA event. This would suggest you had a OA followed by a gasping and then drop of of breathing effort. While it appears to be a legitimate CA event, the trigger was probably the OA event. In both cases you can see the impact on the minute ventilation graph. It goes unstable prior to the CA event.

The second event is not quite the same. It looks like you just took a deeper breath and then the effort dropped off to another CA event. It is actually normal to take a short extra deep breath while sleeping. My wife does it on a regular basis every 8 minutes or so. I forget the name but it is considered normal. Your response to it was not quite normal though, and it ended up as a CA event. But, in the scheme of things not a real serious event. Here is what my wife's breathing looks like when she takes the periodic extra deep breath. In her case it does not result in any issue and the breathing carries on at a regular frequency with no events. The first event is right where the green cursor line is, and then you can see the subsequent periodic repeats of it. Notice that there is next to zero impact on her minute ventilation. It remains very stable. She has few issues with CA events (unlike me).

Overall your results are pretty good with an AHI under 1. It looks to me as if those CA events were most likely due to arousal events. You could consider lowering the minimum pressure to 12 to see if that helps. With not sleeping on your back, that may be ok.

Merry Christmas!

Happy New Year,

It looks like the three OA events were likely due to the pressure being lower. When you lower the minimum the ResMed slowly reduces pressure if you are not having any flow restrictions. Flow restrictions are not shown, but outside of the OA events it looks like they are keeping your pressure higher at times. I would guess that the OA event woke you up and the CA was just part of waking up.

All in all you have a pretty good balance of CA and OA events, with a reasonable total event frequency. If you are generally sleeping well, I think you are doing very well with your settings. You have made a very significant improvement from where you started with your first OSCAR posts. If the OA events start tending to be higher than the CA events, you might want to consider raising the minimum pressure some.

Good to hear you have a new machine and are still getting good results. I also have have issues with Central events. About the only additional strategy that I have used is a fixed CPAP pressure mode. It may help or it may not. About the only way to know is to try it. The rule of thumb is when converting from Auto to CPAP is to start with the 95% pressure value. On this night it is 13 cm. I tried quite a few different fixed pressures and what I attempted to do is balance the OA events with the CA events. If CA's are higher than OA then try a lower pressure, and if OA's are higher than try a higher pressure. The theory is that higher pressure are likely to cause CA events, while lower pressure will cause more OA events, so you are trying to find a sweet spot in the middle. In general you are trying to find the lowest pressure that results in an acceptable number of OA events. Keep in mind that you should stay at one pressure setting for several nights before changing the pressure.

I would leave the EPR the same at 3 cm full time.

Hope that helps some,

I was meaning the 95% pressure from the night you posted. It was 13.1. See this snip:

But a more accurate place would be to go to your Statistics tab and get a longer average of what it would be. See this snip from my wife's OSCAR. Pick the longest time span that represents a period after your last change to the setup.

But, keep in mind this is just a starting point. You will have to manually adjust it up or down based on your outcome.

I would suggest going to the Statistics tab and set the report to a custom Date Range with the radio button at the bottom, and set it for the time you had the pressure at 13.6 to see what the breakdown of events are for that date range. But the much higher number of CA events would suggest the pressure may be too high. It looks like you tried a couple of nights at 12.0. I would suggest going back to that pressure for at least a week to see if things get better or or not. Check the breakdown of event times over the time as well to see if CA's go down without OA going up. The idea is to try to get them more in balance or at least get the pressure down as low as it can go without OA events dominating. When doing this I found small changes get lost in the noise. It is better to make 1 cm changes minimum until there is a clear break point in the number of OA events going up. Once you get close to an optimum pressure then you can try smaller changes to get to the optimum point.

I am afraid I have never been able to correlate how I feel in the morning to my AHI score. When I get up I have no idea what the score will be until after I check the machine screen to see what it is. I just have faith that a lower score is better if I get a reasonable sleep.

I am afraid I do not have experience with either. The Oximeter should confirm apnea events with lower O2 during the events.

I sounds like you would provide competition to Björn Borg with your heart rate.

On pressure the normal response is for CA events to go down when pressure is reduced. Before you go for higher pressure I think I would go down first to see if there is a point where OA events become a problem. If you are like me CA events can be quite erratic. My CA events typically are double my OA events, but they vary a lot from night to night. It takes a long time to determine where they settle out.

Yes, in theory if you lower EPR by 1 cm that increases effective pressure by 1 cm. The issue however is that it only has this effect on the exhale part of the cycle. So it will depend on what part of the cycle is causing the OA events as to whether or not you benefit from this higher net pressure on exhale. My final resolution on it is that the proof is in the eating of the pudding. Try it and see what impact it has for you. This said I think I would try lower pressure first to see if there is a point where OA's start to increase.

After I wrote this I got to thinking that your CA event frequency may be related to your slow heart rate. I have the opposite issue. I had been taking 5 mg of bisoprolol (beta blocker) mainly for blood pressure reasons. However it reduces my heart rate, but no where near your low 30's. When I was having issues with lots of CA events I got to thinking that it may be due to poor circulation due to a lower heart rate. I asked my doctor if I could cut my dose in half. I now take 2.5 mg daily instead of 5 mg. I believe my CA frequency has gone down. My current long term average is an AHI of 0.75 with the CA portion being about 0.5. You may want to discuss with your doctor. Not sure if there is a drug that does the opposite to a beta blocker and speeds up the heart rate.

I don't think you can selectively edit out sections of the data, unless it is a separate session. In the bottom left of the Daily screen there is a session information box. You can check and uncheck those boxes to suppress sessions. They are not deleted, just suppressed for the display of sessions you want.

On lowering the CA frequency about all you can do is keep lowering the pressure until OA's become a problem.