jnk wrote:Physician wrote: . . . several certified sleep docs . . . agreed ResMed should add MEAN LEAK to the LCD Sleep Report . . . .
I have seen leak charts where the software-collected median for the night looked great, but the chart looked like an 8.0 on the Richter in Arousal City. The 95th centile value seemed to me to be the most useful number (if the choices are maximum, 95th centile, or median, that is) that I would have personally chosen to put on the screen for a heads-up to the patient or clinician in those instances. Maximum would be falsely alarming. Median could be falsely comforting. 95th is juuuuuuust right, IMO, for saying "Dude, hook me up to check the charts, would ya?!"
95% can be falsely alarming OR falsely comforting.
If the 95% is, say, 15L/min, it's easy to assume that since that's well below the Red Line, you couldn't possibly have a leak problem even though you were leaking at 13L/min all night long. I personally think leaking all night long even at something that's only half the Red Line value is likely to affect therapy or patient comfort or both. In that case, the 95% Leak Rate is falsely comforting.
And many newbies look at that 95% number when it's say 25 L/min and conclude (falsely) that they've got a major leak problem going on without ever realizing until they look at the Leak Rate graph that 90+ percent of the time, they have no detectable leak and that one 25 minute leak accounts for the alarming 95% leak rate figure. In this case, the 95% leak rate is falsely alarming.
And the fact that the Leak Rate number on the LCD is not
labeled as the 95% number also leads to confusion in my opinion---particularly on the part of newbies who are very worried about whether they have leak issues: I was one of those worried newbies not too long ago. But because I had other issues, I decided to put "leaks" on the back burner for a while. Then once I started looking at the graphs, I realized I really didn't need to worry about leaks since my leak rate is typically 0.0 for well over 80% of the time even on a "bad" night where I had two or three 15 minute detectable leaks at most.
Me personally, I think the only way to provide meaningful data on the LCD is to
provide and
label both the 95% leak rate and either the mean or median leak rate. It's only by looking at the two numbers together that you can determine (1) if you are having short-term, but really big leaks and (2) if you are having middle-sized leaks for most of the night. In either case, I think you'll be more comfortable and get better therapy if the leak issues are addressed instead of ignored.
I also think that since ResMed will not or cannot make the software directly accessible to
all S9 users, they have some responsibility to make sure the numbers on the LCD actually provide meaningful information. In my case, I know the 95% leak rate number is largely meaningless because it seldom reflects the reality of what really happened in the night as far as my leaks are concerned.
