(10-13-2013 05:43 PM)rgrxdp Wrote: I had 73 AHI during my sleep study, but CA ( I guess that means central apnea ) was 0. Now that my machine is set at pressure 10, I have about 10 or 11 AHI with about 9 of that CA. I this for real? Why would pressure make my CA worse...?
(10-13-2013 10:19 PM)PaulaO2 Wrote: To the original poster:
Yes, it happens and is quite common. I would not worry about it for right now. How long have you been using the machine?
If it has been more than a few weeks, let the doctor know. What he will probably do is drop the pressure down a few points and let you get used to that then raise it back to the treatment pressure.
It is fairly common that, at first, standard PAP treatment (the purpose of which is to prevent/reduce obstructive apneas) may cause an increase in Central Apneas. But as the body gets accustomed to PAP treatment, the Central Apnea Index (average number of central apneas per hour) usually gradually diminishes until it no longer dominates the AHI.
Often (but still only for a minority of users) EPR, Flex or other forms of exhalation pressure relief can increase the number of central apnea events. But exhalation pressure relief can also decrease the number of obstructive events, especially when using an auto-adjusting APAP machine.
When the CAI does not reduce to acceptable levels within a few weeks or months, then, depending on how large the CAI is, you may qualify for an Adaptive Servo Ventilator (ASV) machine. ASV machines may take longer to get used to and comfortable with, but are able to prevent/treat both obstructive and central events.
I think the relevant US Medicare rules are something like this:
(1) the CAI must make up a majority of the CAI
(2) the CAI all by itself must be over 5.0
(3) an ASV titration must demonstrate that ASV treatment significantly improves the AHI (like, by a factor of two of more, I think)
I think some private US medical insurance companies have stricter rules, such as that the CAI must be 15.0 or higher with the patient's present PAP machine.