Reza

And I don't think there's a clear path, but I'll just share the pings that I got.

The pings that I got was to go back and be like, wait, is this real?

Because the one time I saw a patient with acute leukemia whose PAO2 was a fake out.

But again, just for clarity, in that patient, the PaO2 on the ABG, which here is 51, as low as a fake out, but the SaO2 in that patient was normal.

So I'm starting to wonder, wait, is this that situation?

And I think that the case for that situation, although intriguing, is weakened by the fact that the hypoxemia is dynamic, that he wasn't hypoxemic when he came in and he is now.

And so I'm holding on to that possibility.

But more alarmingly, a thing that you pinged, Prof. Rez, is the Ras-Bur case.

So Ras-Bur case is unfortunately a notorious trigger for methemoglobinemia and hemolysis in patients with G6PD deficiency.

So this is an important concept to put out there, which is that...

Well, oftentimes when you're giving Raspuricase, you don't know if the patient has G6PD deficiency or not because it's acute and important enough.

This patient's gender, him being a man, puts him at risk for this X-linked deficiency.

And what can happen is that Raspuricase essentially induces reactive oxygen species that both destroys the hemoglobin and the patient gets a hemolytic anemia and also oxidizes the hemoglobin and results in methemoglobin anemia.

So I think you have that ABG, and I think as you alluded to, one powerful step that you can do right now is to add co-oxymetry and look for methemoglobinemia on that ABG.

Yeah, and I think those are the two pings I got.

Is this real, fake PaO2 from leukemia, or is it another fake out from methemoglobinemia?

What are your thoughts?

Prof. Rez, I'm going to make a bold claim.

I think this is my favorite case of all time.

Because this is the case that I would title the double negative.