Okay, what is happening here...

Oops I forgot the original question

Is it just me or does it look like the APAP pressure's not responding (enough) to those apneas? What are the numbers on the "Events graph" - when it says Apnea = 13, does that mean there were 13 apneas or is that the duration or what...??

Now can I make two rants: it's really hard to see the pressure changes and how they correlate with the events because the events are not plotted versus time. Well there's that ramping graph, but hell if i can make any sense of that - it's just a line graph and it's hard to see where each event is (that AHI graph is totally useless IMO). The pressure graph is so compressed it's hard to see the difference between two different pressures. And I totally don't know how to interpret the Evetns graph. Oops that's 3 rants.. Sorry 'bout the rants (I'm a spoiled puritan bennett user).

Hopefully someone else with much more wisdom than myself will respond to you.

Snoredog wrote:You are already 2 cm higher than your PSG titration, you don't win any prizes for using a higher pressure.

Hmm... that point prompted me to go back and review my spreadsheet data from when I had the machine set 8-15.

The objective of raising the min. was to see if the result would be positive... as per the data I appear to have been doing as well back then as I am now set at 10-15 and most certainly better than 11-15 of last night. So, back to 8-15 it goes. No sense using more pressure than necessary.

Snoredog wrote:3. AHI is the SUM of both AI and HI. If you had a AHI=0 at 10 and it went to AHI=8 it could have went
there because of a higher HI count seen

I tried to find it but don't see where he talked about either AHI, HI, or hypopneas at all. All he seems to have mentioned are apneas. Either I am not reading it right, or he's edited it.

a higher HI count seen which don't mean anything on that machine.

Why is that? What about a person who has an AI=0 before therapy? How will they ever know if their therapy is improving their OSA if what you say is true? Would they need different make or model of machine? What machine would be better in that case?

LoQ wrote:

Snoredog wrote:3. AHI is the SUM of both AI and HI. If you had a AHI=0 at 10 and it went to AHI=8 it could have went
there because of a higher HI count seen

I tried to find it but don't see where he talked about either AHI, HI, or hypopneas at all. All he seems to have mentioned are apneas. Either I am not reading it right, or he's edited it.

As I was reading your response I thought: "ah someone who has carefully read the post".

With respect to my numbers I mentioned an index once here: "I went for a period of 7 days where AI was reported as 0. "

My edits are as follows: "<---- these are a count of the # of apneas from the detail charts (NOT AHI, AI or HI)" and "I will see about posting up the details for the worst night a little later when I get home." I did not remove any text.

LoQ wrote:

Snoredog wrote:a higher HI count seen which don't mean anything on that machine.

Why is that? What about a person who has an AI=0 before therapy? How will they ever know if their therapy is improving their OSA if what you say is true? Would they need different make or model of machine? What machine would be better in that case?

l

The Resmed machines tend to score hypopneas approximately 2x higher than other machines. This does not mean they are bad machines but just that the user needs to take this into account when considering their numbers as reported on a Resmed box.

For example... my numbers for last night: AHI = 6.4 AI = 0.4 HI = 6.0 Leak = .06 L/sec. That HI index in reality is approximately 6.0/2 = 3.0 which means my AHI really is 3.4 which is a very reasonable number.

It was that AI number having gone up that I was concerned about. <break to fire up Resscan> Last nights AI = 0.4 corresponds into 4 specific apnea events (note no mention of index here ) last night that occurred about every hour starting at 1:30am.

BTW for those reading... changed my range to 8-15 for last night and will leave it there. Despite being titrated at 8 my machine tends to spend the majority of the night in the 10 - 12 range. It does seem they did not quite get it right during titration.

Looks to me like events are occurring in REM, since they occur in the last section of the night. That means a night with a lot of good REM may have more "apneas." In one sense, at least, that can be a good sign, in my opinion. A night without much REM may give you a better score, but that's not always a good thing, considering. So the numbers are useful when averaged over the week, but don't let a "bad" night, or two, throw you--that night may have been good in some ways.

It is important, in my opinion, to remember that the events are scored according to average ventilation as deduced from air flow. As I understand it, with ResMeds, if the reduction in average ventilation during the ten seconds (or longer) is 74%, the event will be scored as a "hypopnea"; if the average reduction in ventilation is 76%, it will be scored as an "apnea." At least that is my conclusion based on my understanding of the definitions used by ResMed:

An apnea is defined as a greater than 75% decrease in ventilation. The device
algorithm scores an apnea if the two-second moving average ventilation drops
below 25% of the recent time average (time constant 100 seconds) for at least
10 consecutive seconds. A hypopnea is defined as a 50% to 75% drop in
ventilation. A hypopnea is scored if the 10-second moving average ventilation drops
to between 25% to 50% of the recent mean for at least 10 consecutive seconds.
Definition of apneas and hypopneas is based on the patient flow signal

Echo, on the ResMed charts, the number on top of the red line is the number of seconds the "apnea" lasted. Every time there is any flow limitation that meets ResMed's definitions, the AHI triangle ticks up higher for that hour, then it resets to zero for the next hour. That allows you to see in which hour(s) most of your events occurred, at a glance. How steeply the angle rises indicates how the events are bunched together. Not the best system, I agree, but it has a logic of its own as far as convenience and speed of seeing info. Not defending the charts, though--just explaining them.

jnk thanks for the explanation

An update...

Sore lower back is now gone and my therapy readings for the past 2 nights have gone back to pre-sore back levels.

Now the muscles at the back of my neck are quite sore such that turning my head is somewhat painful but this does not seem to be affecting the numbers

Glad to hear the good news!
O.

Glad to hear it!

Next thing that will be sore are either your fingers or your wrists.. from all the cpaptalk surfing

echo wrote:Glad to hear it!

Next thing that will be sore are either your fingers or your wrists.. from all the cpaptalk surfing

I work for a web hosting company... so I spend my entire day clicking 'n surfing.

And as if I don't get enough... then I go home and start over again with the clicking 'n surfing.