Ventilator Leak Data

Spikes in the lead rate do play an important role as they can lead to displayed or non displayed hypopnea or apnea events which lowers your blood oxygen saturation and gives you a feeling of suffocation. Regretably, except for being intubated for three weeks last summer I have little experience with ventilators/respirators - I truly wish I could share more with you but I am sure there are plenty on here who do have more experience than I. I am just parroting what I have read and heard over the past several months really; along with a small measure of logic.

I would take up the issue with my MD's. I know that in my case, although I have not seen my respirologist as of yet, all of my other MDs have suggested infusion of a small amount of oxygen to stabilize my SaO2 at night; perhaps one or two L O2 to start... let's see what it does for you. I called the local supplier of concentrators (oxygen) and then another and then another. NONE of them will sell me the unit! They all charge the same rate for a clunker and that is $395 a month. I picked up a used clunker for that the other day and am going to try to pick up a new clunker stateside for $500-600, a Mobilaire Platinum V. I have ordered the plumbing parts already and even managed to find the inlet nipples on my mask(s) for O2 infusion. However, on the suggestion of yet another friend online here I am going to go more complex and I am going to put a 'valve' in the airline so that the oxygen does not back up into the CPAP machine and create a hazard. I am also putting inline, while I am at it, a very fine particulate filter that claims to filter bacteria out as well (and I am all for that since it was bacteria in my lungs that put me on life support for almost a month last summer... bacterial pneumonia.... and if you haven't experienced it, don't bother. I empathize with weak. It took me four months of intense effort just to be able to roll over in bed. I could not walk nor climb stairs for some time after coming off life support, all my muscles and my diaghram had atrophied. I am still only at 70% lung capacity and that is when I am blowing into their stupid little tube for all I am worth. Well guys, what about when I am deep asleep? I'm not inhaling and exhaling for all I am worth then, am I? Go figure.).

Leak data is very valuable... you are looking for the flat line that indiates a constant leak rate which is probably the intrinsic leak rate of the mask you are using due to the exhaust ports. I am generally pretty good with the masks I mentioned. Now I need to address the SaO2 issues and that may turn out to be MY magic bullet, who knows? All I can tell you for a FACT is that the MD's don't know it all.... each has a bit of the puzzle and their are bits that none can assist you with and you need to educate yourself and TELL THEM what it is you want. Just keep at it. Never give up and be a pitbull when you latch onto something new. We are all here to be of assistance as we go through this together and very often in a discussion like this, where YOU think it is only YOU that is benefitting, in fact, everyone is taking away something for consideration. Don't be afraid to ask what you consider to be 'dumb' questions as we are all learning from it and the only 'dumb' question is the one that is never asked.

I started a new thread that has the information from the ventilator for one day (including the graphs) plus the two consecutive days of pulse ox monitoring (my monitor) where one day was really good and the other indicated a few drops below 90%. I also included the ventilator summary report for those that are interested in that.

The ventilator situation is frustrating because the DME only gives me certain pages. I had to specifically ask for the detailed graphs for specific days.

Madalot wrote:I started a new thread that has the information from the ventilator for one day (including the graphs) plus the two consecutive days of pulse ox monitoring (my monitor) where one day was really good and the other indicated a few drops below 90%. I also included the ventilator summary report for those that are interested in that.

The ventilator situation is frustrating because the DME only gives me certain pages. I had to specifically ask for the detailed graphs for specific days.

I the DME printing the stuff on paper? Trying to save paper or ink? Would he send the whole report by email? Or is he just ignorant?

Madalot wrote:

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????

Let me take a stab at this particular question.

Yes, you are correct that over the past two weeks your leak rate is probably under better control. Why? You have var less variance between the min and max and the average. The week of the 23rd of July had a much wider swing between the minimum, maximum and average.

Since the maximum might just be time when you removed the mask for a few minutes, you should focus on the swing between minimum and average. This will tend to show a representation of the leak rate. In this case the week of the 23rd shows a difference between minimum and average of about 6 points. But the last two weeks show a difference of about 2.5 points. That's a statistically significant closer variance.

Now, for the tough part of this. Remember that when you look at averaged data the peaks and valleys can be hidden in the average. It is possible on "bad nights" the variance is greater. It is also possible that you are (for whatever reason) more sensitive to the sound of a mask leak. I personally know that some nights have have very few mask leaks but it keeps awakening me when it does. Other nights I sleep right through it. The leak rate might be the same, but how I react to it appears quite different.

So, mask leaks may or may not be linked to the quality of your sleep.

ozij wrote:

Madalot wrote:I started a new thread that has the information from the ventilator for one day (including the graphs) plus the two consecutive days of pulse ox monitoring (my monitor) where one day was really good and the other indicated a few drops below 90%. I also included the ventilator summary report for those that are interested in that.

The ventilator situation is frustrating because the DME only gives me certain pages. I had to specifically ask for the detailed graphs for specific days.

I the DME printing the stuff on paper? Trying to save paper or ink? Would he send the whole report by email? Or is he just ignorant?

The FIRST time we did a download and I got my copy, it was the report, over 50 pages long. Subsequent downloads and my request for a copy give me 5-10 pages MAX. I've asked about getting the entire report, but they say they don't give that to patients. When I say that I got it the first time, they just say I shouldn't have. When getting it yesterday, I had to ask for specific dates (I uploaded one day that I feel I had a problem, but I'm not sure which day it was) and also had to specifically request the summary page.

JohnBFisher wrote:Now, for the tough part of this. Remember that when you look at averaged data the peaks and valleys can be hidden in the average. It is possible on "bad nights" the variance is greater. It is also possible that you are (for whatever reason) more sensitive to the sound of a mask leak. I personally know that some nights have have very few mask leaks but it keeps awakening me when it does. Other nights I sleep right through it. The leak rate might be the same, but how I react to it appears quite different.

So, mask leaks may or may not be linked to the quality of your sleep.

Thanks, John. I think I'm like you in that sometimes a leak wakes me up and other times I sleep right through it. I can remember some nights waking up, hearing the leak and adjusting the mask before I go back to sleep. I'm sure there are other nights that it leaks, but I don't hear it.

I have gotten to the point that unless something really unusual happens, I do NOT get up during the night at all. Once I'm hooked up, I stay that way until I get up in the morning. Once in a blue moon something will happen and I'll take everything off and get up, but it's not very often.

Madalot wrote:Hi TorontoCPAPguy --

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).


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.

I would suggest (and again, I am not an MD) that from my own experience your SaO2 can jump all over the place depending on how tired you are, how deeply you are sleeping and how deeply you are breathing - to such things as how much salt did I take in today? What are my allergy symptoms if any? Etc. My own SaO2 is all over the place and that is with zero apnea events and perhaps one or two hypopnea events during the night recorded by the S9Auto. And my SaO2, when it plumments, PLUMMETS! Night before last I had loads of dips into the low 70's and felt awful when I got up for the day. Last night I did not sleep especially well but my SaO2 was generally about 90%. I am hearing that an SaO2 that is fairly level at 95ish produces a very restful and replenishing night of sleep. My rehab MD's tell me that this will also lead to much higher liver function and better performance of medications that I am taking and at the same time will throw drug interations out of whack. I may need to take less of one and more of another. Quite amazing what a healthy well performing liver does for one's body. I meant to ask but did not have time... spleen producing insulin; what effect would the better night with higher, more stable oxygen levels have on my spleen and on how my own insulin is performing on blood glucose. I did learn one thing and that is that ANY exercise is better than none for diabetics and that IT DOES NOT MATTER if you exercise before you eat or after. So this business of an after-dinner walk for the constitution and digestion is balogna. The same effect is achieved from exercise at any time of the day.

I empathize with your inability to exercise as I am being poked and prodded and being called lazy and an 'old man', etc. Not very nice. I guess folks that cannot breathe with anything in their stomache (even water) simply cannot appreciate how difficult it is. Nor can they appreciate what hot humid air does to one's ability to exercise (simply walking). Talk about frustrating. Today I am going to experiment and am about to get out and take a walk with an empty stomache (I did have some breakfast 5 or more hours ago). I used to love walking and could walk for miles; no more.

So, to address your comments regarding worrying if things change - you need to know WHY they changed. And it could indeed be tied into the seal of that mask! What are the other numbers looking like? Number of apneas/hypopneas, AHI, etc. When taken all together you get a better picture of what is going on and for my part, I try to compate the SaO2 readings through the night (recording oximeter Contec 50E) to any other data that may be affecting it.

You can rest assured that unless you are trending downward SaO2 there is probably nothing to get excited about and even if your ARE trending downward SaO2, you need to find out why before getting excited. It could indeed be a mask seal issue... insufficient air getting blown in and down she goes. I cranked my pressure up a smidgen the other night and it seems to have improved things for me; and I have been watching the performance of my Mirage Activa and Mirage Quattro and have come to the conclusion that the Quattro performs better, especially when I am dead tired and smooshing my face into the pillow (breaking the seal). Nice thing about the Quattro is that you get these horrendous 'face farts' (pardon) when the seal breaks much of the time and they are so loud that if you were to run a digital tape recorder in VOX mode you would find out how many times your seal broke during the night (in addition to the data from the S9 of course). So, I think that part of my "magic bullet" is likely going to be a full face mask and probably the Quattro although I am going to try a few others for giggles.

Whatever you do or think, remember that this quest for the "magic bullet" is never ending and that what works one night may not work the next. I don't believe that we can be striving for perfection but rather we can be striving for the best that we can be. That's it. For me and for you there will never be "perfection" as it simply is not possible. But we CAN and MUST strive for the best we can get out of this threapy. Hence my trip down into Toronto last week to pick up an oxygen concentrator (used) as I can in no way affor the $395 a month that the DME's seem to all want to rent one. And my next step, if there is improvement, will be to purchase either a good used one or a brand new one at a good price. Wish I could afford a portable one to take with when we travel but they are several thousand dollars which we can ill afford with two teens going through expensive post-secondary school education. We are disabled enough for the government to give us handicapped parking stickers for the cars based on doctor's reports, but not sufficiently disabled to qualify for a pension despite having paid into these plans our entire lives. Go figure. We have a friend who took a fall and has become a quadraplegic with a permanent trache.... one look at his xrays and it is obvious to even a layperson that his neck was crushed. Yet, it took them months and months of fighting with the government in order to get some assistance. Sad story so I am not about to complain about me.

Keep at it! You are on the right path I promise you. As you educate yourself and participate you will begin to understand things better and be able to take valuable information and suggestions from the more experienced home with you and improve your lot. I know it has worked for me and in fact the MD the other day was asking if I had medical background due to my understanding of the numbers. What a shock... as I know that 90% of those on the forum are far more knowledgeable than I ever will be.

Good luck to you and again, we are all here to share a common goal and help one another. You will get there eventually.... I have a hard time remembering what life was like before APAP threapy and as a matter of interest, the medical supervision I am getting from the best MD's is good to have but does not hold a candle to the practical information shared on this forum. I am forever grateful.

torontoCPAPguy wrote:Regretably, except for being intubated for three weeks last summer I have little experience with ventilators/respirators - I truly wish I could share more with you but I am sure there are plenty on here who do have more experience than I. I am just parroting what I have read and heard over the past several months really; along with a small measure of logic.

I would take up the issue with my MD's. I know that in my case, although I have not seen my respirologist as of yet, all of my other MDs have suggested infusion of a small amount of oxygen to stabilize my SaO2 at night; perhaps one or two L O2 to start... let's see what it does for you.

I understand that most people here really don't have any first-hand experience with ventilators, but the information provided helps me understand. I appreciate whatever input I can get.

I've been on oxygen since January and I do feel a difference with it as opposed to without it. My doctor ordered 1-2 liters and I quickly bumped it up to 2 within a couple of days. I tried going without it one night and found it wasn't as comfortable for me.

In the last few weeks, I have opted to turn off the screen on the ventilator because the light is pretty bright. I decided last night NOT to turn it off so that I could look to see what was going on should I wake up with an issue. I woke up at 6:30 this morning, feeling like the pressure was fairly high. I quickly turned over and looked at the pressure, tidal volume and leak rate. My pressure was 17.9, tidal volume was about 395 (I'm set for 400) and the leak rate was up to about 43.

I have two guesses as to what was going on -- either my mask started leaking and it caused the ventilator to ramp up to maintain the tidal volume OR I was having some kind of event that caused the ventilator to ramp up and that CAUSED the leak. I really have no real way of knowing.