Apnea event durations

[JAR14]

Using SleepyHead and CMSD50+ to monitor, I am experiencing many long obstructive apneas of >45 seconds, and some well over 60 seconds. The oxygen saturation can be seen to drop during these long no breathing periods. AHI last night was 24 with obstructive apneas at 124 and 37 of these greater that 50 seconds. The AHI seems to be getting worse as I try to approach 16 cm pressure specified by the sleep specialist. I am currently at 15 cm max, and 13.5 cm min. Has anyone experienced this type of apnea increase going up to higher pressures? Should I be concerned about the drops in SpO2 (78 events, average duration 100 sec) which go below 93? Sleep specialist does not believe in SleepyHead monitoring, and blew off the data when I showed the results on my laptop in his office.

When showing your sleep doctor data from your machine, it may help to use reports printed using the manufacturer's program, ResScan in your case. These are professional programs he may be familiar with. But, on the other hand, SleepyHead is better because it is able to show the SpO2 and pulse data conveniently time aligned to the CPAP machine's data.

But if your doctor was unwilling to take the time to look closely at the machine's data, perhaps his issue was that the machine was set lower than the prescribed pressure, so of course it's reporting problems?

Those frequent long obstructive apneas are a serious problem which will surely ruin your health if not prevented.

I suppose the long obstructive apneas are not occurring during times of very large Leak, when your machine is unable to maintain its target pressure?

If not, then my guess would be that the higher number of obstructive apneas when using higher pressure settings may be caused by an unnoticed change, such as while asleep rolling more frequently into a worse position.

Obstructive Sleep Apnea is usually strongly positional, and some of us need to take precautions to prevent rolling onto our back while asleep. Some have found great benefit in wearing a light knapsack to bed filled with something light but bulky. Others wear a teeshirt with a couple tennis balls in a sock or pockets sewn on the back, along the spine between the shoulder blades or higher. Others place long body pillow(s) under the sheet to help keep them on their side. Others, who may be unable to sleep on their side, sleep in a comfortable reclining chair or adjustable bed, so their head and neck are aligned but elevated. Whatever it takes.

If guarding against sleeping in a worse sleeping position is not successful in preventing those frequent long obstructive apneas, then I would think higher pressure settings would be needed, such as raising the Min Pressure and Max Pressure.

Also, perhaps lowering EPR may help. Higher EPR usually makes it easier to exhale, but may increase the likelihood of obstructive apneas starting after exhalation has finished but before inhalation has started, while the pressure is still low.

It appears that you have been struggling to raise your pressure settings to your prescribed pressure.

I use high pressure settings, and I am a mouth breather using a full face mask. I find I must use a mask liner to control leaks and eliminate mask burping/fluttering/trumpeting.

I wish that ResMed would have displayed greater concern for patient welfare by including the gentler AutoSet For Her treatment algorithm as an option in the standard A10 AutoSet, but unfortunately they did not. I think many men might find they would have fewer issues with leaks and with air swallowing and wide pressure swings if given the choice of using the For Her algorithm.

Take care,
--- Vaughn

Greetings vsheline! Thanks for your input & suggestions.
When I showed the Dr. the SH data, I was at an earlier prescribed pressure of 10 cm. He then increased the max to 16cm and the min to 13 cm. When I tried the prescribed settings, had problems keeping the mask on and simply could not sleep. So I went to lower pressures and started to work my way up gradually.

The Simplus mask has been very good in terms of fit to my face and almost no leaks.

Your information on positional impact on apneas was most interesting. I am a back sleeper: 1] Allergies & Sinus drainage prevent me from sleeping on my stomach. 2] Full face masks seem to shift if I lay on my side. 3] When sleeping on my stomach, I would have to breathe thru my mouth. That said, perhaps I should sleep on my stomach, breathe thru my mouth as needed, and compare the SH data with that obtained when sleeping on my back.

Your comment, "I find I must use a mask liner to control leaks and eliminate mask burping/fluttering/trumpeting.", is something that might help at the higher pressure. The burping/fluttering/trumpeting is a very apt description of what I sometimes experience.

My EPR is currently off, simply because the Dr. did not indicate that it should be on and at what level. Is this a patient discretionary parameter?

The successes reported on this forum of totally controlling sleep apnea have made me very optimistic about "whacking the sleep demon". I am very grateful for the depth of knowledge and positive way it is shared by the members.

May the ZZZZs be with you.

[Dawei]

Re: the doc blowing off your presenting him with data from SleepyHead: My thought is, as Vaughn mentioned, that it may well be simply because he knows the mfgr's software and can easily read data in that familiar form but not from different software. Re: nsherry's reply--that makes me wonder if your sleep specialist is actually a doc who has sleep medicine as his sub-specialty (or one of his sub-specialties), since sub-specialty medical training is what it takes for a doc to become an actual sleep specialist.

David

[vsheline]

Also, perhaps lowering EPR may help. Higher EPR usually makes it easier to exhale, but may increase the likelihood of obstructive apneas starting after exhalation has finished but before inhalation has started, while the pressure is still low.

My EPR is currently off, simply because the Dr. did not indicate that it should be on and at what level. Is this a patient discretionary parameter?

Yes, EPR is usually considered just a comfort feature which users may adjust as they may desire. But some doctors prefer that their patients not use EPR.

EPR has been known to significantly increase the number of central apneas in some users (approximately 30% of new users, I think). If using EPR does not increase yours much, no problem there.

Also, because EPR keeps the pressure low at the end of exhalation, the very time we are most susceptible to obstructive apneas starting, in fixed-pressure CPAP therapy mode when raising EPR theoretically the IPAP setting should also be increased equally higher. But in general these are never adjusted together, so increasing EPR tends to increase the number of obstructive events, unless using an auto-adjusting model like yours, in which case the machine will adjust the pressure higher as may be needed, as long as it does not max out (try to raise itself higher than the Max Pressure setting).

Note that EPR ends when inhalation begins, and if an obstructive apnea begins before inhalation begins the low EPR pressure does not end, except after about 10 or 15 seconds EPR eventually will end and the pressure will return to the normal IPAP pressure. However, if the airway has already collapsed the return to normal IPAP pressure is unlikely to end the apnea. Usually an arousal to a more shallow sleep state is needed for us to exert enough effort to reopen the airway.

[JAR14]

In my view anything longer than 45 seconds is a problem worth discussing with the doctor, but I think some doctors are not alarmed unless an apnea lasts closer to twice that long.

In my experience, central apneas are usually far less of a strain on the body than obstructive apneas. With a central apnea not caused by paralysis or injury, as soon as we get the urge to breathe, we do, usually without much stress.

Your profile says you are using less than your prescribed pressure. If you are using less than your prescribed pressure, it is probably very important to avoid your worst sleeping position, which for most of us usually is rolling flat onto our back while asleep.
[/quote]

Thanks for the comment.
[/quote]
You were spot on! Have not been sleeping on my stomach because prior masks have either leaked badly and/or simply shifted. Tried stomach sleeping with the FP Simplus, and it was doable. 1st nigh AHI was 8.15 and 2nd nigh 2.81 with NO obstructive apneas over 10 seconds. Dramatic improvement; Thanks so much.