A regular CPAP delivers the same pressure, apnea event or not.
An autoPAP delivers pressure according to your need. So if you are not having an event, it figures out what pressure you need to keep your airway open then reacts when you have an event by raising the pressure in response.
The good thing about using an autoPAP is since no two nights are the same, why should your pressure be the same? It can react to whatever you happen to need each night. And needs change. Stress, food intake, liquid intake, medication, day of the week, etc all factor into the quality of sleep.
Since you know 13 is good, you may try to use 11 as the bottom number and 15 as the top. The machine will not go lower than 11 and won't go higher than 15. You can then look at the data to see what pressure ranged while you slept. You'd need to collect data for about 10 nights before you see a trend.
Apnea Board Moderator
Breathe deeply and count to zen.