Dr. Sara Crager covers management of VQ mismatch.
Great job. Excellent idea in regards to the ongoing ventilator waveforms discussions. I actually think Vent Waveform Weekly (or whatever you would call it) would be just as cool as the ECG Workout. I'd subscribe for sure.
Hi Sara, I wanted to clarify some things about VQ mismatching where there is an apparently high dead space fraction. I have noticed this in my patients not just in dead space conditions like profound shock or massive PE, but in patients with more ARDS (i.e. shunt) physiology. Most recently I had this occur in a patient with cardiogenic shock and pulmonary edema, and titrating the PEEP from 14 to 20 did increase the EtCO2 significantly, much more closely approximating the PaCO2. Also quite recently I had a patient with ~60% BSA burns and trauma, but we were reluctant to increase the PEEP as aggressively due to significant volume loss. Is recruitment by PEEP titration known to be useful in some of these these patients? Would inhaled pulmonary vasodilators have a role here too? How would you differentiate the mechanisms of thisEtCO2/PaCO2 gradient (shunt vs. dead space vs. both)? What other tips do you have for managing VQ mismatch in the shunting patient? Thanks!
Love these ICU Fundamental lectures! At what value for the Physiologic Dead Space Fraction do you begin considering inhaled pulmonary vasodilators? I'll admit I've never calculated these values for my patients before, so I don't have much concept of what is considered severe enough to change management
Thank you so much for putting all this together
Look forward to interesting waveforms...
What you do matters.