Erratic rollercoaster pressures dreamstation

[rexwater]

Devoted CPAP user * 12 years. Retired nurse familiar with ICU ventilator settings and dialysis machines. On my second machine.... dreamstation 3 years. Have had essentially no problems for 12 years ...until five days ago. Settings 4 to 16 averaging 14. Suddenly and abruptly 5 days ago pressure drops too early at end of inspiration and pressures back up too early at end of exhalation. The pressure change is sudden abrupt and significant causing masks jump sleep disruption and inability  to fall asleep. Equipment provider tested machine with manometer and says it is functioning within the limits and my numbers look good. Of course they only want to assess the machine not the patient and the Machine ?At the same time it started to display a 1% mask fit and AHI went up significantly. Luckily my old Resmed machine was still working and I've been using it. The MD changed prescription today to 11 to 18 to try to overcome these issues. Things are now worse!! I'm convinced they are issues with the sensor and or Electronics. I set the machine while ago to a low of 12 and a high of 12 so there is NO range. The pressure still drops down almost to nothing on exhalation. There is not enough pressure to keep my airway stented open. I can't seem to convince anyone that there is a machine problem. I go out of the country in three days tomorrow is my last day to try to resolve this. I use my CPAP every single night and also during naps so I'm a bit panicky and perturbed. Any advice suggestions will be truly appreciated. I have changed the mask and the tubing to rule out those  being the cause of any issues. Thanks for any help or advice you have

[jaswilliams]

What is your setting for flex on the Dreamstation. Try changing it what you describe is a common feeling with flex, but it seems odd to get it now after using the Dreamstation fir a number or years

[rexwater]

Thanks. I does it on A flex and C flex...it seems to do it the least if I turn flex off and set on CPAP only with pressure of 10 or 11....but still unbearable

[Sleeprider]

Rex, your pressure range is very wide for a Dreamstation. The Philips machines are not very responsive to flow limitations and the fact your machine is pushing the upper bounds of your pressure settings suggests you should be using much higher minimum pressure. The Philips Cflex and Aflex are only designed to provide up to a 2-cm pressure relief at expiration, and it usually returns to CPAP pressure prior to inspiration. There is a predictive aspect to Flex that does not exist with the Resmed EPR which is more like true bilevel. If you are experiencing larger pressure swings, then something may be wrong or defective with your machine. It would be interesting to see a detailed chart from OSCAR, which can actually let you see your respiratory flow wave-form on a breath by breath basis, as well as machine pressure and respiratory events and statistics. It's a free program you you should have the expertise to understand it; however we will gladly help.

Have your machine checked for pressure delivery. Most medical equipment suppliers have instruments (manometers) that can check the pressure delivery at the mask. It is also possible that the machine sensor itself will report the pressure anomalies if you use the software. OSCAR is free to a good home: https://www.sleepfiles.com/OSCAR

[rexwater]

Thanks so much for analysis and advice. I finally convinced the MD and device supplier that it was a machine issue. Phillips respironics agrees and wants to evaluate machine. Supplier 'gave' me machine that has 400 hours on it instead of loaner. Problem solved. I was able to educate respiratory therapist and MD how to more effectively trouble shoot machine problems