APAP question

Hi, I have a beginner's question about APAP. When the machine detects what it thinks is an apnea or CA, it raises the pressure. Does this pressure ever come down during the same night or does it stay that high until the morning? Sometimes I am half-awake after this happens and I wish it would reduce the pressure.

Ideally, your machine should be PREVENTING obstructive apneas by keeping your airway open. That’s the point of the positive air pressures. And the algorithms are designed to anticipate a collapsing airway and provide increased pressures before you actually experience an apnea. The machine can detect the narrowing of the airway in a hypopnea and impending obstructive event and increase pressures pretty quickly to avoid it. RESMED says their machines can do so within three breaths. So, my questions would be: 1) what machine and settings are you using? 2) is your machine working properly? 3) And what’s your residual AHI?

It kind of depends on your type of machine, but in general yes each obstructive event, hypopnea even, flow limitation, or snore will cause the pressure to increase. Clear airway or CA events should not cause pressure to increase. ResMed machines tend to raise the pressure fairly quickly and then slowly let it decay back down if there are no further events. The DreamStation machines like to bring the pressure down much more quickly. This sounds good, but through the night the pressure can keep going up and down.

See this sleep report with a ResMed machine. The red pressure trace shows the pressure going up and down during the night. You can see how this relates to the OA (obstructive apnea) events in the Events bar, as well as to the Snore, and Flow Limitation.

Thanks I am using a Sleepmate 10 Auto in APAP mode. I turned EPR off, as I found it easier to breathe without it. At the moment, I am only testing the machine in the afternoon for short periods. I have a full mask and a two nasal masks and am still trying to work out which is best.