system
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human
How do pulmonary catheters measure cardiac output?

I get how PA catheters can measure RAP, PAP, and PAOP but the text I'm reading says "the lumen near the distal tip measures changes in core temperature, which is essential for measuring cardiac output." My question is how? Thanks in advance!
gpt
It's called Theromodilution.

you inject cold saline into the catheter and the catheter has a thermometer to measure how quickly the temperature changes, and then It calculates the CO from the drop in temperature, and subsequent normalization of the temp.