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Flow - GreyParrot - 01-15-2014
May I ask what a "flow " indicates? Last night I have a graph
that starts as always then just stops about halfway through the night.
Every other night it's a tight scribble all night. Was I laying on the hose? Or is that not what it means? I desaturated to 80 once as well 24 seconds but still had ahi of .9
RE: Flow - robysue - 01-15-2014
Quote:May I ask what a "flow " indicates?The Flow graph is the trace of each and every breath you took all night long. That's why it's made up of a whole bunch of wiggles and looks like "a tight scribble" when you look at the data for the entire night. If you zoom in on one small area of the data, you can see the individual breaths.
To help you understand the flow graph a bit better:
The units on the vertical axis are Liters per Minute. The graph is measuring the rate of airflow into and out of your lungs. You are inhaling when the Flow graph is above 0 L/min and you are exhaling when the Flow graph is below 0 L/min. The larger the peak on an inhalation, the deeper the inhalation is; the larger the dip on an exhalations, the deeper the exhalation is. Typically as you settle down into sleep, the flow wave graph becomes much more regular when you zoom in close enough to see the individual breaths; the reason why is simple---sleep breathing is supposed to be much more regular (and quite a bit shallower) than normal wake breathing. Because normal sleep breathing is so regular, it becomes pretty easy to spot the OAs and even the Hs that get by the CPAP defenses even without the event flags to identify them after a while.
Quote:Last night I have a graph that starts as always then just stops about halfway through the night. ... Was I laying on the hose?If there's a break in the Flow graph, that means the machine lost its ability to track your breathing. Why? Well the most common reason is that the machine was turned off or the mask was taken off. We sometimes do that in our sleep. And a few of us are even capable of putting the mask back on in our sleep several minutes to several hours later. But large leaks are another reason the machine might lose track of the breathing. Occasionally there's just a random glitch in the algorithm and the machine loses track of the breathing for a while.
But laying on the hose? Well I suppose it could cause the break in the Flow graph if you're heavy enough to cause the hose to collapse or partially collapse when you are lying on it. The hose collapse would have to be severe enough to interfere with the machine's ability to measure the subtle changes in "back pressure" that are the result of your breathing. So we're talking about a pretty severe pinching of the hose at some point.
RE: Flow - GreyParrot - 01-15-2014
robysue, thanks for the info. Must have been a glitch as all other
info is there in ResScan like always.