Maximum Inspiratory Pressure (MIP) Test

[Will]

My PALS recently failed a MIP (Maximum Inspiratory Pressure) test. He passed the FVC test with 100%. This was the first time he ever experienced this test in the last 3 years since diagnosis. The respiratory therapist recommended a BiPap, but the Neurologist didn't think he needed one. He has little trouble breathing, although he does not sleep particularly well.

Does anyone have any experience with this test or have any comments on this situation?

 

[lgelb]

Will,
Trying a BiPAP at night if he is not sleeping well can't hurt, and might help. Many people start BiPAP before they feel the need.

The PFTs in clinic are (1) often inconsistent (2) not necessarily reflective of real-world respiratory demands/responses. Not sure what you mean by "failed" -- below normal leaves a lot of room. I would write down and track all respiratory test results (raw numbers) as you go. None of these are binary. Also, some people adapt better than others to diminished respiratory drive/capacity/ability, so two people w/ the same FVC or MIP may have very different needs for BiPAP.

I'd make sure you get one with a data card that you can read yourselves, and that you know how to change the settings to address what you see in the data/in his sleep. It's unlikely that this is a "set it and forget it" deal.

Also, there are many types of masks, so don't be afraid to experiment to see what works best. You might ask your DME to include a Circadiance nasal mask in their assortment since it's lighter (cloth) and seals easier than a lot of other masks. It's not the most thrilling for going out, but since he would be starting at home, it could work well. Some people prefer nasal pillows, depending on nose/nostril shape/symmetry.

 

[affected]

Did they not also do the MEP Maximum Expiratory Pressure? Usually both are done. The second is even more important as PALS tend to experience a lot of problem with breathing out and expelling CO2. These 2 tests tell more about the condition of the breathing muscles, rather than the condition of the lungs function and capacity.

My PALS had these tests about 9 months ago when he was still walking, eating, using his arms and speech was only slurred. I don't know what you mean by failed though. My PALS scored around 85% FVC but only 30% MIPS/MEPS.

Amazingly, the rest of his body has continued rapid deterioration, he can only eat a little puree, can barely speak, has lost arm/hand use and can only really stand to transfer, yet his FVC was 50% 4 months ago, but they couldn't even attempt to do these tests now as we wouldn't get any seal with his mouth at all and the saliva would cause issues too.

He isn't using bpap though I think we are getting close to it.

 

[lgelb]

Tillie,
With the results/status you describe, I can't understand why he isn't on BiPAP. His CO2, for example, is likely higher during sleep as his drive drops and you are never going to know that with a MEP in clinic. 50% FVC is actually a conservative threshold for starting it. It may actually help w/ saliva as well.

 

[affected]

we have ftd and he refuses to accept progression until absolutely forced ...

 

[hjlindley]

It is been my experience that Lori is correct that the respiratory measurement equipment at clinic is not as accurate as that in the pulmonary department. The first thing I would do, because it sounds like he needs reliable data, is do what I did and request a referral to the pulmonologist associated with the clinic. My forced vital capacity was measured at 72 it clinic and when we went up to pulmonary it was a hearty 86. Remember that the equipment in pulmonary Is calibrated more frequently and is far more accurate. But everyone is right that the CO2 builds up at night and so BiPAP, particularly something like a trilogy, might be helpful.

 

[FSHolbrook]

The question I would ask is he or has he been to an ALS clinic? We have monthly clinics here in Fargo and the pulmonary test there are identical as the ones at the hospital. I would go with what to pulmonary folks suggested.

Rick

 

[Will]

Rick, This was done at the MDA/ALS clinic in Phoenix.

I have gotten some additional info from the written respiratory therapists report:

FVC = 104%
FEV = 84%
PEF is 2.96 liters/second
NIF is -12 mmHg
Oximetry is 97%