So, I was at the nursing home today, and a nurse comes in to check on the elderly lady I’m visiting. The nurse has a device, shaped like a 2 by 10 by 18 cm box with a digital readout. Attached is a cable, some sixty centimetres in length, with a litttle cushioned clamp on the end. She clamps this last over the fingernail of Mrs. Visitee, and proceeds to measure her blood oxygen level.
The nurse couldn’t answer my questions, so I’m asking the masses:
What is this thing called, and, more importantly, how on earth can such a device work? It draws no blood, so what is it sampling? Heat transmission? Temperature? Whatever it is, I’ll bet it’s clever.
Thanks ahead, wolfStu