capnography waveforms recorded in the VitalDB #742

Dear, VitalDB team.

I need your thoughts on the capnography waveforms recorded in the VitalDB dataset. Above is a snippet of the capnography and airway pressure waveforms recorded from patient ID 1.

I am confused about why there is a shift in the airway pressure waveform relative to the capnography waveform. Since these patients are under surgery and mechanically ventilated, is it expected to see a shift of this nature?

For instance, in the first image, the airway pressure rises when the capnography waveform declines. In the second image, the airway pressure rises when the capnography waveform increases. Both waveforms are from the same subject.

Regards

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