Inspiratory flow restriction?

[Urimare]

Dear all,

Working on getting used to CPAP for three months. Still little positive result (though my AHI has dropped from 41 at sleep test to mostly <5 from day 1.

Tonight was a 'good' night, in that I slept long and without waking up too much. AHI also low. But I feel horrendous at waking up.

I was looking at my flow rate patterns and unsure how to interpret - but when I compare it to some OSCAR wiki pictures it seems like there is some flow limitation due to the non-rounded curves at inhalation? Am I seeing this correctly? Thank you in advance!

[G. Szabo]

Indeed, you have a flow limitation, which can be mitigated by adjusting the pressure. To find the correct range, I suggest turning the instrument to APAP mode and running it with 8 cm minimum and 14 cm maximum pressure with the ramp off.

[gainerfull]

Echoing G, you're running too low of a pressure at the moment - you likely need to add 1-2 cmH20 to your minimum so you're only seeing flow limitations every 1hr-1.5 (during REM)

[Urimare]

Thank you! I don’t think I’m allowed to change the settings myself unfortunately. So will need to pick this up with clinic.

My doctor first wanted to see how a new mask would work (no difference except less leakage) and give it some more time since it’s only been three months - but i am going to collect this data to request a new earlier appointment. My current pressure was the one from the start, and at my first interim consultation a few weeks ago they were satisfied based on my AHI, but I did mention the continuing if not worse fatigue.

I was already keen on requesting an increase as I was seeing a lot of UF2 (50% flow restriction) events in clusters of an hour or so when I switched on user defined events in Oscar (though the clinic was less receptive to this as they were not considered clinical events, though looking at the patterns in Oscar the only difference I saw with hypoapneus was the duration)

[SarcasticDave94]

I can't tell you to do the edit, however most people do edit CPAP for themselves.

The Simplus was a decent mask for me with I used it.

Most Fisher and Paykel full face masks need to be loose. Allow the CPAP to inflate the cushion. Use the top of the head strap to determine the up and down area the mask sits on your face. Then edit the bottom set to have moderate tension, as well as the top set. They do not need to be tight.

[Sleeprider]

Flow limitation has shown a positive response to the use of EPR (exhale pressure relief) which is a form of bilevel therapy. Increasing pressure (pressure support) during inspiration counters the increasing inspiratory flow limitation caused by collapse of the airway due to the increasing negative pressure as inspiration progresses to its peak flow. Your close-up of your flow shows you reach a peak flow during inspiration which partially occludes the airway resulting in a diminishing flow before inspiration begins. The solution is to increase pressure as your inspiration progresses to counter this. Our wiki on flow limitation shows how the Resmed CPAP with EPR helps to do this. https://www.apneaboard.com/wiki/index.ph...limitation i

I recommend you change your settings to Autoset mode, keep minimum pressure at 8.0, set maximum pressure at 11.0 and set EPR On, full-time at setting 3. This consistent with your current settings resulting in pressures from 8/5 to 11/8 (inhale/exhale). This will result in a significant reduction in the 95% flow limitation and improvement in comfort and sleep integrity. There is some risk that CA events will increase, but we need to see results to decide how to proceed. Your flow limitation is impressive, and if you do this, I may ask permission to use your charts in the wiki linked above.

[Urimare]

Thank you. I unfortunately am not allowed to independently change the settings on the machine. I just called the proivider and explained this - they are allowed to increase pressure but the switch to AutoSet requires permission from the pulmonologist. So I will call the clinic and bring foward a check up appointment to share these findings and see if they agree to this.

After three months of using the CPAP every night and getting AHI<5 I was really hoping for an improvement, but its as if I feel a lot worse! So keen to have them agree to try these settings.

[Nightynite]

Unfortunately this is the normal with the health care community nowadays that monitors and provides adjustments to our needs with pap. They tend to only look at the basic AHI numbers. This board has empowered the user to adjust and fine tune their device based on data so they can benefit health wise.

[Sleeprider]

Let's be clear about this. You may make any changes you see necessary and comfortable. Your DME provider cannot change settings without a prescription. Read the introduction section to the CPAP Manuals and decide for yourself. https://www.apneaboard.com/adjust-cpap-p...tup-manual We know what your problem is and how to solve it. It's entirely up to you whether to use that advise to your benefit.