Abrupt change in AHI

[VegasPier]

I have been using a s9 Autoset since January of this year. Up until a month ago my AHI was what I considered great; normally less than 5 with only a few excursions above that figure.
Now for the last two weeks I've been peaking at 50+ occasionally. Does anybody have any idea of what is going on? Is the machine malfunctioning? The high AHI and snore numbers seem to peak together when the pressure is at the upper limit of 15. I've reset it to 20 for tonight.

Comments? Thoughts? Suggestions?

Cheers, Vegaspier

[zonk]

Hi VegasPier
First of all the machine have no clue if you,re asleep or awake, awake events are meaningless

Couple of questions:
Are you using the machine on auto or fixed pressure? if auto .. what range and pressure stats
What central apnea component of AHI and leaks stats?

[VegasPier]

Hi VegasPier
First of all the machine have no clue if you,re asleep or awake, awake events are meaningless

Couple of questions:
Are you using the machine on auto or fixed pressure? if auto .. what range and pressure stats
What central apnea component of AHI and leaks stats?

Hello Zonk,

Thanks for the reply. I've bee using the auto pressure settings of min 9 and max of 15. I reset to max of 20 for tonight.

I'm afraid that I don't understand the second question. I'm sorry. Could you help me out?

Cheers, VegasPier

[Peter_C]

Silly question? Any leaks showing up? Mouth-breathing can do exactly that. Also, my mask went a bit wonky and is leaking at the swivel, and my AHI went from under 10 to 30+ these last two nights. I know you're wearing a FFM, but since it fits under your lower lip, if your mouth is opening enough, it could possibly create leaks while you sleep?

[PaulaO2]

There's a couple of things to look at.

What kind of events are you having? Are they all obstructive events? Are they relatively the same amount of central, obstructive, and hypopnea events? (this is what zonk was referring to, I think)

Other things to look at:
have you started any new medication? stopped a medication or changed the dose of a medication?
have you made any changes to the bedroom or sleeping pattern?
have you made any changes to the mask or hose?

How do you feel during the day? Do you feel the same as before or are you as tired as your AHI says you should be?

[VegasPier]

Silly question? Any leaks showing up? Mouth-breathing can do exactly that. Also, my mask went a bit wonky and is leaking at the swivel, and my AHI went from under 10 to 30+ these last two nights. I know you're wearing a FFM, but since it fits under your lower lip, if your mouth is opening enough, it could possibly create leaks while you sleep?

Hello Peter_C,

You may have hit on something; mouth breathing. I've had a dry mouth on a few occasions plus I've been awakened with mouth breathing. But why all of a sudden? I've not changed anything that Paula mentioned. I have a new cushion. The one that I've been using is about two weeks old, maybe older. I'll put the new on in and see what happens tonight.

Thanks for the info.

Cheers, VegasPier

[zonk]

Hi VegasPier
AHI include all types of apnea events (obstructive apnea, hypopnea, central apnea and unknown apnea)
Its important to know the breakdown of events, now if we,re talking about the majority of events are central apnea events than you need followup with your sleep physician

Leak rate is important too, looking for leak to be below 24 L/m over the course of the night. High leak render the data useless

[VegasPier]

There's a couple of things to look at.

What kind of events are you having? Are they all obstructive events? Are they relatively the same amount of central, obstructive, and hypopnea events? (this is what zonk was referring to, I think)

Other things to look at:
have you started any new medication? stopped a medication or changed the dose of a medication?
have you made any changes to the bedroom or sleeping pattern?
have you made any changes to the mask or hose?

How do you feel during the day? Do you feel the same as before or are you as tired as your AHI says you should be?

Hello PaulaO2,


Peter_C has given me some items to think about. Answering your questions: No to all of them. As far as feeling tired, not any more than before.

Cheers, VegasPier

[VegasPier]

Hi VegasPier
AHI include all types of apnea events (obstructive apnea, hypopnea, central apnea and unknown apnea)
Its important to know the breakdown of events, now if we,re talking about the majority of events are central apnea events than you need followup with your sleep physician

Leak rate is important too, looking for leak to be below 24 L/m over the course of the night. High leak render the data useless

Hello Zonk,

I think that you have zeroed in on the problem; leaks. One leak rate was almost 155. It was associated with a AHI event. In fact, all of the OA or H events were associated with leaks.

Cheers, VegasPier.

[Peter_C]

Last night was my first night with my new mask (new replacement of the same mask). My leak rate dropped to 0.3L/s and while I didn't wake 'refreshed', neither did I struggle to get up like I have for the last number of weeks. Plus my AHI and AI dropped back to my norms of less than 10, and 2.

Depending on your face and mask, you can get large leaks with an open mouth. For me, mouth breathing is somewhat random, but also based on how exhausted I am, or if I am ill. Generally I can do well with a nasal mask, and only switch to my FFM when I am ill. Just something to consider.