leak data

[steve7e]

Hi, I don't understand my leak data as is shown on my Spirit(on console).
1) What are the parameters for an acceptable leak rate?
2) What are the leak rates for people using the Swift, which I use?
My leak rates vary from .7 to 1.1 usually .7-.8 using a chinstrap, I am trying to figue out if I mouth breath or mouth leak. Thank you

[Goofproof]

If it's considerable lower with the chin strap, I would say you have your answer. Without your leaking. And thats bad for you.

[john5757]

[quote="steve7e"]Hi, I don't understand my leak data as is shown on my Spirit(on console).
1) What are the parameters for an acceptable leak rate?
2) What are the leak rates for people using the Swift, which I use?
My leak rates vary from .7 to 1.1 usually .7-.8 using a chinstrap, I am trying to figue out if I mouth breath or mouth leak. Thank you

[dsm]

Mask Leak rates:

Masks:
The 'fixed' leak rate of a mask is determined on a chart supplied with the mask (see the booklet that came with it). This rate varies depending on the pressure from the machine in use with the mask.

Some machines (such as my PB330) allow us to set the leak rate of a mask so that the machine can factor that in when trying to asses the accidental leaks in a mask. My breeze mask when used at 15cms pressure has a 'fixed' leak rate of 27 l/s (litres/second). My Ultra Mirage F/F mask at the same 15 cms pressure has a 'fixed' leak rate of about 48 l/s.

The ResMed machines allow you to choose the mask in the users menu.

Machine's reported leak rate.
Many newer machines will capture data showing what air leaks out above and beyond what the mask's know 'fixed' leak rate is.

The 'fixed' lead rate comes about because all masks have deliberate 'leak' holes used to help clear out the co2 we breathe out while doing xPAP therapy.

Mismatching a mask to a machine can cause some problems :-

1) The machine will incorrectly report the masks accidental leak rate
2) We may breath in too much co2 that should have been cleared

Cheers

DSM

PS: I recently had someone send me a Resmed Elite (sent it over 3000 miles) because they said it was faulty. The problem reported was that the machine would shut down after approx 10 mins use My thorough tests showed it worked perfectly. Resmed tested it and said it worked perfectly. The user said he had tried 2 different masks - Ultra Mirage F/F and Activa.

On deeper investigation it turns out the user was selecting ULTRA on the Elite menu when in fact he should have selected FULLFACE. That combined with an accidental leak at his face, was registering in the machine as excessive leakage and thus shutting down the machine.

Mask machine mismatch is a bigger problem on newer machines that have airflow sensing circuits in them. It causes a different problem in the older machines (Remstar Plus, Innvocare Polaris (without SoftFlex), etc: etc:). Those machines have little awareness that a mask may be leaking badly or at all.

Any machine that is a BiLevel or has Cflex, EPR, SoftFlex, or is an AUTO or is one of the S7 & S8 Resmed models, or is a PB42x model, has airflow sensing circuits. Modern xPAP machines are very sophisticated.

D

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): resmed, breeze, mirage, activa, cflex, auto

[john5757]

DSM

That quite right and thanks and we need to ask the user what is the mask setting is. A high leak rate will show if the ResMed machine is set for a standard for the Swift instead of the Mirage setting. I also noticed when I tried different mask setting on the Spirit it does has some effect on the flow limitation set point in which the machine will increase pressure in response to "flatting"

[wpinef]

I spoke with the patient advocate at resmed and she told me that any leak rate above .4 for the swift is a problem. I had been using a large pillow on mine but was seeing .7-.9 L/s leak rates but changed to the small pillow and my leak rate dropped to around .2L/s. maybe the pillow size you are using is to big?

Dave