DP, what you've described is what's passed down to doctors and DME's by the machine manufacturers' reps...to an auto-titrating machine temporarily (a week, a month) to find an effective single pressure, then put the person on a straight CPAP machine at that pressure.
What many actual users of autopaps who post to the message board have found is that an autopap can, in many cases, provide more comfortable treatment, night after night, than being on a straight CPAP machine. Often they need that "worst case scenario" 90th or 95th percentile pressure for very short periods in any given night. And are treated effectively at much lower pressures the majority of the night. Less pressure generally means less chance of masks springing leaks, less chance of aerophagia, less difficulty breathing out, less noise from mask exhaust...lots of "less is nicer" stuff that can let people sleep better.
There are some people who prefer, or do better, with a single pressure. It can be a very individual thing as to whether a straight cpap machine or an auto-titrating machine suits each person better. Or a bi-level machine, for that matter.
DP wrote:This means that you actually have to begin having an apnea before it will increase the pressure.
If you mean there has to be the beginning of some
flow limitation before an autopap will increase the pressure some...yes. If another cm or so of pressure corrects the the flow limitation and keeps the situation from possibly progressing to an hypopnea or an apnea, that's good.
However, speaking of "Begin having an apnea" sounds like you're talking about an autopap just sitting there blowing a low pressure
until an apnea actually occurs. I'm no expert on autopaps, but I don't think that's quite how they work. It's my understanding (I'm not anything in the health care field at all) that most autopaps are designed to correct lesser flow limitations before there's more collapse. Not just wait for an apnea and react after the fact.
Quite a few people on this board use a pressure range with their autopaps that is rather different from the usual range of 4 - 20, or 5 - 20 for a temporary titration at home. Many set their autopaps with the lower pressure up closer under the single prescribed pressure. The machine doesn't have as far to travel when more pressure is needed to prevent events.