help... Suspicous Flow Rate and Flow Limitations, bothersome Aerophagia

[SarcasticDave94]

If it helps on getting switched to BPAP, mention the discomfort with CPAP aspect. "It feels uncomfortable" (fill in the info as applicable) may be suitable to consider the change according to the doc. It depends on the info the doc wants. Some will comply with the request for BPAP for comfort, others due to better therapy abilities available with the BPAP.

[Sleeprider]

Normal I:E ratios will range from 1:1 (both the same) to 1:3 (inspiration time 1/3 of expiration time). A typical I:E ratio is 1:2. A more common way of expressing this is to divide the expiration time by inspiration time and express expiration as a fraction of one, so a 1:2 ratio becomes 0.5 to one. Inspiration time longer than expiration time suggests an anomaly that is the result of an obstructed airway with high flow resistance or flow limitation, poor lung compliance due to COPD, asthma, or other pulmonary condition, or weak inspiratory muscles or neurological problems. Serious conditions can be ruled out or confirmed with a simple pulmonary function test that can be performed in your general practice physician's office or by a pulmonologist. It is a routine examination using spirometry. If PFT shows normal function, the an inverse I:E ratio may be a symptom of sleep disordered breathing and flow limitation. In most cases, a long inspiration time can be resolved by using pressure support to supplement spontaneous effort with a mechanical ventilation assist, i.e. pressure support from a bilevel PAP.

In the chart posted of therapy 2/10/24, we saw a insp time of 2:48 and exp time of 1.75 or, 1.42 to one. This is inverse spontaneous ventilation ratio (greater than one to one) to the expected which would transpose the I and E times. The chart shows a persistently high flow limitation or upper airway resistance. Although the AHI is low at 1.37, this kind of inspiratory flow limitation would cause a great deal of respiratory effort to be expended to get a full breath, and the person with this pattern complains of arousals, unsatisfying sleep, fatigue and daytime sleepiness. This can be remedied with bilevel, which can be prescribed by the doctor solely on the basis of those comfort complaints.

[Barefooter64]

It took awhile but the Aircurve 10 Vauto is here and was used last night.  So far it's not encouraging but we assume there will be some acclimation needed.

Min EPAP:  6
Max IPAP: 14.   Started at 17 but she was feeling smothered and panicky.  It stayed at 14
PS  8

The good parts

1. I:E is not inverted anymore.  Med I:1.42  E:3.76.
   
2. Flow limitations are no longer constant.
   

The bad parts

1. AHI last night was 9.72   CA:6.31 with vast majority happening when she was trying to get to sleep.  The balance was mostly OAs
   
2. Aerophagia worse again.
   

PS/FWIW:  Worked with TheCPAPShop to get the updated script and AirCurve10 Vauto.  Ordered the card to cloud form but they ran out so substituted data type for same cost.  The update of prescription was done via a video appointment with SleepCareOnline.

[Sleeprider]

Wow! Where did PS 8.0 come from? Let's start over.
EPAP min 6.0
Max IPAP 13.0
PS 4.0
Ti Min 0.3
Ti Max 2.8
Trigger: Med
Cycle: Med

[Barefooter64]

Those setting made a big difference.  AHI less than 1 each night now. 

After a few nights it looks like her min OA avoiding pressure is something above 6.5 as each time the machine trends down to about 6.5 an OA happens in a few minutes.  I've bumped min to 6.8 to see if that makes a noticeable difference.

[Sleeprider]

Don't hesitate to increase EPAP min to 7.0 or your best judgement. Everything else can stay the same. Post a chart when you get a chance.

[Barefooter64]

The last 2 nights have had AHI below one.  Generally she feels like she is getting better sleep than she was with the AirSense.

The slight increase in Min EPAP may have helped a little.

Aerophagia has been an issue both nights.

[Sleeprider]

Drop max IPAP to 13 cm and see if that helps with aerophagia. That will still leave plenty of room to increase for obstruction and keeps the flow limits down. I'm glad sleep is better.

[Barefooter64]

After almost 2 weeks the AirCurve is providing her good benefit.  The trigger was changed to High as it wasn't staying with her on E to I transition.  Max was changed to 12 due to more days of aerophagia.  AHI is typically 0.9 or less.