Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

Respironics no leak; Resmed huge leak
#31
No, No, No and one time again: NO!

that is not how it works! - or at least to my believe which does not have to be near the "truth".

First: the machines do not increase the pressure during leaks - their taks is always: keep the pressure steady! (the pressure decreases during the inhalation - it increases during exhale)
It does that by changing the airflow - the amount of air flowing towards you - or turbine speed.

If you open your mouth everything goes sideways - period! It does not matter if you put yourself before a jet-turbine or someone is "playing CPAP" with a fan - if your mouth is open there simply is no "therapeutic pressure" anymore!
The pressure is really meant to keep your airways open. If the mouth opens the whole airflow is going the way of the lowest resistance - which is: right out of your mouth. Deeper in your airways is simply no longer any pressure.
The pressure the machine measures comes from one point only: your nostrils or the smallest passage in your nose - that is the only point where pressure builds up - that is what the machine measures.
After that point it has much more space (like in your mouth!) and the pressure drops towards 0!

In other words: the difference between what you are having and no treatment at all is: your are comsuming energy and making some noise (probably) - that is about it.
And I really doubt that it is healthy for any tissue down the road to be tortured by nearly 10 times the amount of air flowing through it.

Your machine says something about 5 liters per minute as your respiratory ventilation - but it puts something in the 60ies through your nose! - that is more than 12 times the amount!? .. you cannot really consider that healthy?

Why do you think there are FULL FACE MASKS? Do you actually believe someone is wearing those just for "comfort"?

As for this "Philips" can handle more leaks.
Philips tells you the total leak rate - that includes the intentional leak rate from your mask (which is meant to stop suffucating - for those who do not breath through their mouth).

Whoever put a fixed value on the leak rate for philips is simply out of their bloody mind! - REALLY I MEAN THAT EXACTLY!

If you have CPAP 6cmH2O and your mask vents 25 liters you simply cannot say: everything below 60 liters is OK!
If you have CPAP 20 cmH2O and your mask vents 60 liters - well ... you should have gotten the point already. If not, this is a waste of time.

ResMed on the other hand shows you only the unintentional / real leak - there the vent rate of your mask (which is pressure dependant) is already substracted.
Someone has said: 24 liters is a good threshold. - the actual value is debatable - but it is a common "marker".

If you would have a real leak (mouth leaks have their own category) the machine would be able to keep the pressure up LONG AFTER those 24 liters.
How long dependants on 2 things: maximal turbine speed and your current pressure where the leak occurs.

Be assured: if both machines are able to provide the same maximum pressure they can both handle identical leaks!

If you leak at 4 cmH20 (which is he lower end of the machines) you can have mway more exzessive leaks than at 20 cmH20 (which is the upper end).

In order to establish the pressure the machine have to pump air - continously. That means: turbine speed. More pressure = faster turbine speed.
All this machines are build to be able to keep the maximum pressure up + the vent rate of any Full-Face-Mask + a fair amount of leaks.
In your machine-manual there should be something about the maximum pressure in case of failure: THAT is the upper end of the turbine speed. (should be something around 50 cmH20)

Bi-PAPs / ASV usually have "stronger" turbines (as they are designed for higher pressure) - they can consequently handle much bigger leaks than CPAPs.

Really: please go and get yourself a FFM - or at least a chin-strap .... or the very least you could do is: speak to your doctor about your leak-PROBLEM!
Post Reply Post Reply
#32
(11-14-2017, 12:21 PM)TBMx Wrote: No, No, No and one time again: NO!

that is not how it works! - or at least to my believe which does not have to be near the "truth".

First: the machines do not increase the pressure during leaks - their taks is always: keep the pressure steady! (the pressure decreases during the inhalation - it increases during exhale)
It does that by changing the airflow - the amount of air flowing towards you - or turbine speed.

If you open your mouth everything goes sideways - period! It does not matter if you put yourself before a jet-turbine or someone is "playing CPAP" with a fan - if your mouth is open there simply is no "therapeutic pressure" anymore!
The pressure is really meant to keep your airways open. If the mouth opens the whole airflow is going the way of the lowest resistance - which is: right out of your mouth. Deeper in your airways is simply no longer any pressure.
The pressure the machine measures comes from one point only: your nostrils or the smallest passage in your nose - that is the only point where pressure builds up - that is what the machine measures.
After that point it has much more space (like in your mouth!) and the pressure drops towards 0!

In other words: the difference between what you are having and no treatment at all is: your are comsuming energy and making some noise (probably) - that is about it.
And I really doubt that it is healthy for any tissue down the road to be tortured by nearly 10 times the amount of air flowing through it.

Your machine says something about 5 liters per minute as your respiratory ventilation - but it puts something in the 60ies through your nose! - that is more than 12 times the amount!? .. you cannot really consider that healthy?

Why do you think there are FULL FACE MASKS? Do you actually believe someone is wearing those just for "comfort"?

As for this "Philips" can handle more leaks.
Philips tells you the total leak rate - that includes the intentional leak rate from your mask (which is meant to stop suffucating - for those who do not breath through their mouth).

Whoever put a fixed value on the leak rate for philips is simply out of their bloody mind! - REALLY I MEAN THAT EXACTLY!

If you have CPAP 6cmH2O and your mask vents 25 liters you simply cannot say: everything below 60 liters is OK!
If you have CPAP 20 cmH2O and your mask vents 60 liters - well ... you should have gotten the point already. If not, this is a waste of time.

ResMed on the other hand shows you only the unintentional / real leak - there the vent rate of your mask (which is pressure dependant) is already substracted.
Someone has said: 24 liters is a good threshold. - the actual value is debatable - but it is a common "marker".

If you would have a real leak (mouth leaks have their own category) the machine would be able to keep the pressure up LONG AFTER those 24 liters.
How long dependants on 2 things: maximal turbine speed and your current pressure where the leak occurs.

Be assured: if both machines are able to provide the same maximum pressure they can both handle identical leaks!

If you leak at 4 cmH20 (which is he lower end of the machines) you can have mway more exzessive leaks than at 20 cmH20 (which is the upper end).

In order to establish the pressure the machine have to pump air - continously. That means: turbine speed. More pressure = faster turbine speed.
All this machines are build to be able to keep the maximum pressure up + the vent rate of any Full-Face-Mask + a fair amount of leaks.
In your machine-manual there should be something about the maximum pressure in case of failure: THAT is the upper end of the turbine speed. (should be something around 50 cmH20)

Bi-PAPs / ASV usually have "stronger" turbines (as they are designed for higher pressure) - they can consequently handle much bigger leaks than CPAPs.

Really: please go and get yourself a FFM - or at least a chin-strap .... or the very least you could do is: speak to your doctor about your leak-PROBLEM!

Thanks for your response.  I was trying to get an answer to a question, which I've now gotten from another forum.  I'm not interested in getting involved in the contentious discussions over leak standards.  I've had two sleep studies, both using nasal masks, and none of the sleep technicians or sleep docs suggested that I needed to use a full face mask.  Although you obviously don't trust the Respironics engineers, the Respironics machines that I have used for more than a decade rarely report large leaks.  That is good enough for me.
Post Reply Post Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Do I have a leak?? Fixit50 6 133 Yesterday, 11:15 PM
Last Post: ajack
  Resmed F20 leak rate tricountytrail 14 351 11-17-2017, 08:08 PM
Last Post: HalfAsleep
  Major Mask Leak Haynbo 3 107 11-14-2017, 01:36 PM
Last Post: jaswilliams
  Leak rate (and AHI) brojohn1611 6 362 11-14-2017, 01:06 PM
Last Post: jaswilliams
  ASV: Anyone Used Both Resmed and Respironics ASV? VisitorX 8 259 11-13-2017, 07:11 PM
Last Post: VisitorX
  [CPAP] Auto mode on Respironics IS better! TimtheEnchanter 3 173 11-13-2017, 02:42 AM
Last Post: ajack
  Ever used a Respironics ASV? Please take this survey. VisitorX 0 86 11-07-2017, 07:42 PM
Last Post: VisitorX

Forum Jump:

New Posts   Today's Posts




About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.