I googled it and wished I hadn't! But they stick a hole in ya arm take out the blood put it in a HUGE Ronco record cleaner like whizzy thing, put the white stuff in a placcy bag, to use later for folk what is poorly, stuff the red stuff back in somewhere. That last bit can make your lips tingle a bit.
I had a white blood cell 'harvest' a couple of times in the late '90s. They take your blood out of one arm, put it through a centrifuge, so that the different componenets of your blood seperate, take off what they need, and then once through the centrifuge and back together again, they put your blood back in the other arm.
I've sat and watched as all 8 pints of mine have come out (no, not at the same time!
), been spun around, and then been addded back into me! It takes a couple of hours to do
White blood cells, Leukocytes (lah dee dah!) just look like a creamy red coloured version of blood.
but I think the nurse was a bit distracted last week - she shoved the needle in a bit clumsily and it bloody well hurt! In fact, the arm was throbbing for a couple of hours afterwards.
I am normally quite easy to get blood from as I have veins like drainpipes, but the last time I had to give blood, the nurse obviously hit a nerve, and yes, my arm was sore for a while too. That said, I've also had a vein collapse before. That was a little bit strange and the best way to describe it was that it was a sudden tingling sensation, as if something had just gone bang/kaput. And yes, it hurt for a while afterwards.