That thing where your cells "need oxygen" and "can't function without it" sounds like a story made up by Big Hemoglobin to sell more beans for the iron content.

...

So I'm back from the emergency room, where I went after consultation with the chemo after hours triage and a couple questionable numbers on the pulse oximeter. Which I calibrated against the ER machine. I did also get the ER machine to throw some bad numbers, but in a way that suggested that it may have been an error caused by not enough red blood cells for the light to interact with correctly. Which is delightful and hilarious. We were there for not quite 4 hours. I gave someone in the waiting room my orange soda and marzipan bar, since it looked like she needed it more than I did.

I'm not yet at the threshold where the ER wanted to give me a transfusion. We'll see how it goes.