Ventilator Leak Data

I'm sorry, but based on what I've been reading here, I have another question.

I know the ventilator is different in many ways, but I'm wondering about the leak rate and if that's different also. When I got the ventilator back in February, we went over all the information that shows on the display. The RT said that as long as the leak rate was below 60 l/min, it was fine and that if it was in the 30's, it was good.

But I'm reading here where people are talking about leak rates MUCH lower than this. Is it different because it's a ventilator or are these leak rates I'm experiencing (always at least mid to upper 30's) something to address?

Kathy, I dont have any answers for you, but I want to bump this back up in hopes someone with the knowledge will see it.

Jeanette

Edit your post and change the subject line to, "Ventilator Leak Data??"

This will help some of the ventilator experts pick it out of the index of topics.

newhosehead wrote:Kathy, I dont have any answers for you, but I want to bump this back up in hopes someone with the knowledge will see it.

Jeanette

Thanks Jeanette!!! I appreciate that bump.

roster wrote:Edit your post and change the subject line to, "Ventilator Leak Data??"

This will help some of the ventilator experts pick it out of the index of topics.

Done!! Thank you for that suggestion.

Madalot,

This is what I understand to be the case.

Thefixed leak rate data is directly related to the mask type. It doesn't matter if your machine is
a cpap, auto, asv, avaps or other type of pressure/volume regulating machine.

There are two types of leak data. Fixed leak as per the manufacturers charts for a given mask,
and accidental leak (self evident).

There is one notable difference between Respironics Machines and Resmeds that can lead to
confusion & that is that on Respironics machines, all leak data (both fixed and accidental) is
shown in the nightly data whereas on Resmed machines one chooses the mask type & the machine
uses internal tables to subtract off the known leak rate for the chosen mask.

So on Respironics machines one sees the total leak data all in the reports & on Resmed machines
(all being correct when choosing the mask off the mask menu) the only data should be the accidental
leak data.

When your RT says your machine should show under the 60s but is best in the 30s, the RT is meaning
that 30s is where there is little to no accidental leak & above the 60s means the machine is probably
getting to the level of leak where it needs addressing. It is very difficult to not have some accidental
leaking.

What tends to happen is that over time we get used to the pattern of leak data & get to know what is
acceptable & what causes us problems with our therapy.

When you have the nightly data to review, the main thing is to look for spikes or exceptions. IIRC your
machine will show a heavy black line over the leak data if the leak rate is considered excessive. My
Respironics ASV certainly will do so.

Good luck

DSM

I think that regardless of the mask or the machine what you might want to aim for is a flat line leak rate... it may not indicate minimal leak but chances are that it is indicating just that, whereas if the leakage is all over the place it is a sure sign that you have an issue.

dsm(as guest) wrote:Madalot,

This is what I understand to be the case.

Thefixed leak rate data is directly related to the mask type. It doesn't matter if your machine is
a cpap, auto, asv, avaps or other type of pressure/volume regulating machine.

There are two types of leak data. Fixed leak as per the manufacturers charts for a given mask,
and accidental leak (self evident).

There is one notable difference between Respironics Machines and Resmeds that can lead to
confusion & that is that on Respironics machines, all leak data (both fixed and accidental) is
shown in the nightly data whereas on Resmed machines one chooses the mask type & the machine
uses internal tables to subtract off the known leak rate for the chosen mask.

So on Respironics machines one sees the total leak data all in the reports & on Resmed machines
(all being correct when choosing the mask off the mask menu) the only data should be the accidental
leak data.

When your RT says your machine should show under the 60s but is best in the 30s, the RT is meaning
that 30s is where there is little to no accidental leak & above the 60s means the machine is probably
getting to the level of leak where it needs addressing. It is very difficult to not have some accidental
leaking.

What tends to happen is that over time we get used to the pattern of leak data & get to know what is
acceptable & what causes us problems with our therapy.

When you have the nightly data to review, the main thing is to look for spikes or exceptions. IIRC your
machine will show a heavy black line over the leak data if the leak rate is considered excessive. My
Respironics ASV certainly will do so.

Good luck

DSM

Thank you so much for taking the time to explain this. I really, really appreciate the information.

This is all very confusing, isn't it? This is definitely a Respironics Ventilator. I need to review the leak data for the past few days and look at the chart. I'm a little tired tonight but will do it in the next day or so.

torontoCPAPguy wrote:I think that regardless of the mask or the machine what you might want to aim for is a flat line leak rate... it may not indicate minimal leak but chances are that it is indicating just that, whereas if the leakage is all over the place it is a sure sign that you have an issue.

I'm sitting at my desk and briefly looked at the leak chart for the last few nights. It's not exactly a straight line, but it's definitely pretty even and not all over the place. When I look at the summary, I find something very interesting: It's listing the statistics a week at a time, and the leak statistics for the week of 7/23/10 are:

Max 167.5
Min 32.2
Avg 38.64

But the statistics for the last two weeks are like this:

Max 44.2
Min 34.9
Avg 37.49

If I'm reading this correctly, it looks like my leaks are more under control now than they were at the end of July. But I have absolutely no idea why.

Or am I confused????

Those both look pretty good!

The minimum is about right for most masks. The average is only a few points (liters per minute) above that, so no problem.

That larger maximum is what I get when I take my mask off before I turn my machine off. It might just be for 30 seconds or so, or it would have more impact on the average.

The lower one, in the 40's, was more likely a time when you turned the machine off before taking your mask off.

Everything looks good overall!

It would still be nice to see the leak data line. But overall there are no issues. There still might be times during the night when leaks wake you up, make noise, etc.

Michael

unadog wrote:Those both look pretty good!

The minimum is about right for most masks. The average is only a few points (liters per minute) above that, so no problem.

That larger maximum is what I get when I take my mask off before I turn my machine off. It might just be for 30 seconds or so, or it would have more impact on the average.

The lower one, in the 40's, was more likely a time when you turned the machine off before taking your mask off.

Everything looks good overall!

It would still be nice to see the leak data line. But overall there are no issues. There still might be times during the night when leaks wake you up, make noise, etc.

Michael

Thanks Michael. I can scan the document and post it. I'll try to remember to do that tomorrow -- if I can remember the website people use for that????? Can someone help me out here???? I only used it once or twice and just don't remember.

From an old thread

Catnapper wrote:Hi
These are directions written by GoofyUT several months ago. I hope he won't mind if I paste them here.

Its easy!!!

Take a digital photo, load it onto your computer, and then upload it to a "photo hosting" service on the web. http://www.photobucket.com is VERY popular, easy to use and FREE!!

When you upload a photo to Photobucket, it'll generate some code that it lists in a line under the picture, and which is called a "tag." You highlight that line and copy it to your clip-board using "copy" in your Edit menu.

Then, when you want to upload a photo to cpaptalk.com, you click on the "Img" button at the top of the text page for a post (to the right of "Message body") then click "Paste" in your edit menu, and that tag line will be pasted right there. You then click the "Img" button again.

You're free to add any text that you want before or after you paste the image code in using the "Img" button.

Now me again.
You have to have a user name and password to make an account on photobucket. I use the tag that is the html one. They make several tag lines for you. So, sign on, browse for a picture, then upload. Not hard at all. You won't see the picture until you preview your post. It will show up then.

Hope that helps. t-bone showed me how to do all this in about 5 minutes.

Catnapper

Thank you for posting these instructions. I have done it before, but had forgotten the name of the site. I'm writing it down for future reference.

Appreciate the help.

There's a great piece of inexpensive software called GRABIT that will take a scrolling window in one shot and allow you to edit it and save it in whatever format you want prior to uploading to Photobucket; then taking the photobucket url and plopping it into your post. I absolutely love GRABIT... it makes life a lot easier when posting information.

And I must say that the poster that suggested that an extremely high maximum leak rate is exactly right... if you remove your mask before turning off your blower you are going to get one heck of a spike in the leak rate. I generally ignore the leak rate numbers and look at the graph for that reason. The other thing that this points out (isn't group discussion great?) is the number of times you have either lost your mask seal or the number of times you have gotten up to go to the bathroom during the night so it is all good information and will give you an idea of the efficacy of your treatment in conjunction with all of the other data you are being swamped with.

You also, of course, want to get your hands on a pulse oximeter like the Contec 50E that will charge up and record all night (I use a bit of blue masking tape to make sure it is stable and doesn't fall off in my sleep). Your blood oxygen saturation is probably one of the most critical clinical pieces of data that affects your overall health and wellbeing. If you can keep it above 90% or even as high as 95% while you are asleep (constantly, i.e. flat line) you are likely getting a better quality of sleep if your apneas and hypopneas are under reasonable control. I cannot get mine to stay up and flatline about 90% no matter what I do.... even with leak rates of pretty much zero and AHI of 0.0 my SaO2 still goes all over the place many nights and sometimes down into the 70% range which causes blood pressure to skyrocket and causes your autonomic nervous system to, apparently, limit the amount of time in L4 and REM sleep by hollering at you "wake up and breathe deeply". I am about to infuse 2-3L of oxygen into my air line to see if I can get the flatline 95% going.... I am sure that will improve my quality of sleep.

The bottom line is to keep talking and reading and learning and eventually you will understand what all the numbers means and how they contribute to your overall success in treating your OSA and sleep issues. It is NOT just a matter of getting the leak rate down but that is certainly a critical part of the formula and you need to pay close attention to it. I have spend six months going through various masks and various sizes of masks in order to come up with the Mirage Activa nose mask and the Mirage Quattro full face mask as my #1 choices... in sizes that get them to sit on the fleshy parts of my face to maximize the seal. And adjust them EVERY night before retiring while laying down. AND keep your face clean (I use strydex pads to degrease my face just prior to bed always and get a great seal generally unless I mess up the seal adjustments (i.e. the forehead brace that keeps my nose from blistering and the tightness of the straps... it needs to be 'just so' in order to maximize your seal).

Hang in there. It will come eventually and as one friend on here says... the search for the elusive magic bullet seems to get closer and closer such that you can almost taste it. Regretably, your sleep techs and respirologists just do not have enough time to educate you on all things CPAP. You are going to have to be your own advocate.

ONE of the things that will aid sleep apnea in many cases is weight loss; blood oxygen levels can be helped by exercising the diaghram and lungs. I learned something at my diabetes workship yesterday... measure your blood sugar beforehand and then exercise BEFORE you eat; it makes the walking or cycling so much easier as your stomache is not pressing on your lungs and reducing capacity. And for diabetics (any out there) the latest studies show that it matters not if you exercise BEFORE or AFTER eating. Not a smidgen of difference. We are very lucky to have a world class rehab program here in Toronto that is tough to get into but is simply outstanding. TORONTO REHAB - covered for one year 100% by the government. And they only hire the best of the best.

Good luck. Keep reading and learning.

Hi TorontoCPAPguy --

Thank you for all the input you gave. I appreciate your taking the time to share your knowledge and experience on my behalf. There are a few things I want to touch on from your post regarding my situation.

Based on everything I've read here and the input I've received, I feel leaks probably are not playing any significant role. Based on what I've been told here (thank you everyone) I think the SPIKE is from my removing the mask before turning off the vent in the morning. I rarely get up during the night so it's not likely from that.

I thorougly clean my face every night and use an acne astringent to get any residual grease and grime. This has helped tremendously in getting a good seal.

I have a CMS50F pulse ox monitor and do an overnight about twice a week. My numbers have been really good for the last 6-8 weeks, with nothing below 90%. Thursday night's test was an exception, with 3-4 events into the upper 80's with a low of 87%. It's not too concerning and could just be a fluke, but this combined with the "suffocation episode" I experienced a few nights before that where I was awakened in the middle of the night -- it gives me pause and makes me believe I need to watch things very carefully. And my doctor agrees as she ordered the download and overnight (the real one from the DME with their monitor which is more sensitive than mine).

For those that don't know or don't remember, I suffer from a rare neuromuscular disease which causes severe weakness in the arms, legs and for me -- eyes. Last year I started having trouble breathing when laying down, which is a symptom of the disease they suspect I suffer from -- Mitochondrial Myopathy.

In the last 10 years, I've gone from being mildly weak, but able to function and live a normal life, to barely able to do basic things a wife and mother does. It's incredibly frustrating.

Because of this disease, I am unable to exercise at all. I wish I could because I use to love to be physical, but now just walking from one end of the house to the other taxes me beyond anything I could have ever imagined.

Because my breathing issues (and being on a ventilator at night) ARE the result of a progressive disease, I get apprehensive when things change and don't seem as stable as they once were. I have to constantly fight with myself over ignoring the issues or addressing them with determination.