I down to 4 CFM, no what?

djhall wrote:

Too tall wrote:yea I know that. Maybe you can tell me. what is a good chart suppose to look like? is the bottom line suppose to be straight?

With the two lines from Respironics machines the top line is the total leak rate and the bottom line is the machine's best estimate of how much was intentional leak (above the bottom line) and how much was unintentional leak (below the bottom line). In a perfect world the bottom line would be flat and nothing would ever leak except the vent. In the real world, leaks happen. If the bottom line stays relatively close to the bottom of the chart then you are just having small leaks here and there. If you have hills, humps, mountains, then you are seeing times where there is a fairly significant amount of air escaping, perhaps the mask has shifted or you mouth breathed with a nasal mask. That becomes a problem if it gets to the point where top line starts hitting 75 or 80. Past that point the machine can't keep pumping more air to make up for the amount that is leaking and you are going to start loosing treatment effectiveness.

watergauge wrote:

Too tall wrote:I've been lowering my pressure from 6 to 5 then last night to 4. (snip)

FYI, it's not "CFM", the units are "centimeters water gauge", written "cm w.g." CFM (cubic feet per minute) is a flow measurement, a dependent variable, not a set-point. The CPAP machine is set for "cm w.g.", a pressure target, typically in the 4 to 20 cm range. No comment on your "4 cm w.g." setting.
Cheers,
WG

archangle wrote:Nobody uses "centimeter water gauge" for CPAP. It's "cmH2O." However, it's the same thing.

Guest wrote:

archangle wrote:Nobody uses "centimeter water gauge" for CPAP. It's "cmH2O." However, it's the same thing.

So what is your point? Are you just smarted than everyone else?