Auto Missed Series of Apneas: Confused

Last night I had 6 apneas ranging from 13, 17, 21, 13, 13, 12 seonds within a 30 minute period of time. My leak was 00--.02 .......My pressure just before the first apnea was 11.80, went up to 12.6 then steadily decreased finally arriving at 8.80 at the tail end of the series of apneas.........any thoughts why this would happen.........

elg5cats wrote:Last night I had 6 apneas ranging from 13, 17, 21, 13, 13, 12 seonds within a 30 minute period of time. My leak was 00--.02 .......My pressure just before the first apnea was 11.80, went up to 12.6 then steadily decreased finally arriving at 8.80 at the tail end of the series of apneas.........any thoughts why this would happen.........

Perhaps you need more than 11.80 to clear those apneas. Plus starting from 8.8 it is just taking too long to get there.

If it were me, I would bump up my pressure 1 or 2 cm to see how that did me.

elg5cats wrote:Last night I had 6 apneas ranging from 13, 17, 21, 13, 13, 12 seonds within a 30 minute period of time. My leak was 00--.02 .......My pressure just before the first apnea was 11.80, went up to 12.6 then steadily decreased finally arriving at 8.80 at the tail end of the series of apneas.........any thoughts why this would happen.........

Resmed machines will not respond to apneas above a pressure of 10. The Resmed algorithm considers apneas above a pressure of 10 to be centrals.

What Paul said.

Pressure induced apneas happen more frequently above 10 cms/h2O. Pressure induced apneas are breathing cessations that have nothing to do with obstructions, and therefore do not indicate a need for raising the pressure. They are the way some people respond to the pressurized air, when the pressure goes above a certain limit.

Automatic machines have different ways of avoiding pressure induced apneas - Resmed does this by not raising pressure in resopnse to a "stand alone" apnea above 10, since that's a statstically good number. (Respironics jogs your pressure up 3 times tills it figures it should not have and drops it, and Puritan Bennett trys to hear your heartbeat on the open airway, and also lets you define your personal level above which it won't respond.

Were those apneas pressure induced, or obstructive? We don't know. In order to guess at that, we would have to know your Rx, your PSG data, and your present pressure settings.

I would not automatically raise the bottom pressure - unless the Rx or PSG recommend a starting pressure of more than 10. It would also be important to know if central (i.e. open airway) apnea appeared during your PSG, and if yes, when. If those are central apneas, your machine is behaving as expected of it.

O.

Were those apneas pressure induced, or obstructive? We don't know. In order to guess at that, we would have to know your Rx, your PSG data, and your present pressure settings.

I would not automatically raise the bottom pressure - unless the Rx or PSG recommend a starting pressure of more than 10. It would also be important to know if central (i.e. open airway) apnea appeared during your PSG, and if yes, when. If those are central apneas, your machine is behaving as expected of it.

I don't have my PSG results. Doctor and I forgot to get a copy at the end of the appt. I plan to get them when I go for an appt in a few weeks. I do not have any central sleep apena during sleep study. Pressure range for APAP was RXed @ 8-16. I do not know what the tritration study pressure was. With this series of apneas, all occurred within 30 minutes, 2 were close enough together to be overlapped on the apnea markers on the softwared grafts. The pressure just before the apneas began was 11.8 then it went up to 12.6 during the beginning of the apneas, then pressure began to taper as the apneas continued to occur with some increasing in duration. It appears maybe there was a response to the first apnea, then pressure declined without response to additional apneas as if they were not occuring!!!!

As has been previously mentioned, the ResMeds will not pursue an apnea above 10 cm. UNLESS it's preceded by snores or Flow Limitations.
I would suggest setting the minimum pressure to 10 or 11 and see what happens then.

Den