(07-08-2014, 06:43 AM)jty Wrote: The therapy is working well and I have low AHI but I still get multiple apnea and hypoapnea events each night.
My problem is that sometimes the hypo event takes more than 30 sec before the autoset starts raising the pressure and these nights I wake up with migraine.
The machine is NOT designed to increase the pressure during
an event. This mimics part of AASM Clinical Guidelines for Manual Titration Sleep Studies
. If two or more events happen close together the machine will increase the pressure after the second event is over. The Resmed S9 you are using also pretty aggressively increases the pressure in response to snoring and flow limitations.
Quote:Is there a way to make the auto set react faster?
The pressure limits are min 6 and 15 max
There's no way to increase the speed of the S9's reaction. (And it already has a reputation for being more aggressive in its pressure increases.)
You could try increasing the minimum pressure setting
so that (1) fewer events get through to start with and (2) the machine has less far to go when it decides you need more pressure.
To illustrate: Let's suppose that your 95% pressure number is something like 10cm. In other words, your pressure is AT or BELOW 10cm for 95% of the night. This means that you sometimes
need a pressure as high as 10cm to keep the apnea under control.
With a min pressure setting of 6cm the machine has to increase the pressure all the way to 10cm if a nasty cluster of events starts up. And even with its aggressive pressure increases, it's going to take the S9 about 4-5 minutes to increase the pressure from 6 to 10 cm.
With a min pressure setting of 8cm the machine only needs to provide a 2cm increase in pressure when a nasty cluster of events starts up. And the S9 can increase the pressure by 2cm in 1-2 minutes.
So with a min setting of 6cm and a need for 10cm, it can take the machine 4-5 minutes to fully respond. But with a min setting of 8cm and a need for 10cm, it only takes the machine 1-2 minutes to fully respond.
So the critical question is: What is your 95% pressure setting? If it's above 8cm, then increasing the min pressure may reduce the number of apneas/hypopneas that get through the PAP defenses and make it easier for the machine to respond to the ones that do get by.