"Thumbing through" and sorting some my digital breath images I noticed instances of rising FL flagging with sudden sharp drops within about a minute of a "late" Autoset pressure rise. Remembering the similar nature of this thread's OP image the following line of thought came to me.
FL flagging in the OP and my images may have grown more and more "severe" (with no TV drop) because of shape and breath timing changes alone. Airway and wave conditions (a short choke?) degenerated enough to cause a sudden real airflow restricton and tidal volume drop. Such drops are usually followed immediately by recovery breathing causing TV rebound as the OP and my image depicted.
Ideally my (now non-scaleable) readymade graphic snip below would have shown the usual OSCAR TV presentation zoomed a lot more vertically to show more clearly the volume change and timing.
The OP graph scale differences have to be taken into consideration. Nevertheless and to my notion's contrary, the very small, few second drop in TV (circled in blue) is more slight than TV drops shown by the OSCAR TV curve inside the three green rectangles. That small (OP) TV drop relative to the large sharp TV increase (recovery breathing?) begs more data for interpretation, begs FR and respiratory rate curves (if not a leak curve which often suggests intentional or reactive motion).
Here's a thought experiment connecting my image below to mine above. Think of inverting the whole slot with its FL flags having been colored inside with semi-transparent yellow. Then mentally place the FL axis exactly on top of the (red) axis of the TVd with the FL now hanging upside down. Once again, where yellow overlies red the red looks rust color, otherwise a lot more yellow is seen--yellow simply indicating some lack of FL and TVd agreement; the disagreement arises from the fact FL duration and "severity' are impacted by the three shape and timing factors, not just by TVd as is indicated in red and/or rust.
That mental image would be close to the one above, the main difference being that the breathing pattern above (FR, TV, and TVd) consisted of long ramp-like curve outlines, more than three of them. The FR curve below is not ramp like in outline.
It's to be expected that naysayers will claim it's all meaningless, fussy, wasted time and storage here. But pursuit of such things usually leads to better understanding of topics. Even blind alleys taken teach something. I think my later line of thought, here, is not only on topic but plausible.
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