I am now a regular platelets donor. It's a little different than giving whole blood, and cool.
When you donate platelets, a machine next to you spins your whole blood in a centrifuge, takes the platelets (and a little plasma), and returns everything back to you in the same tube.
It takes a hell of a lot longer. Whole blood usually takes less than 10 minutes, while most people take around 45 to donate platelets. I take more than 60 because my veins are so small! (Today the phlebologist told me my vein was only a little bigger than the 16-gauge (c. 1.65mm) needle they used! Augh!)
The upside of the time sacrifice is being able to donate every 14 days instead of every 56. That's 4 times more donations, which is worth the extra hour a fortnight.
I'm usually pretty emotional about donating, but last time I donated, I got an even bigger reality check. I saw the phlebologist filling out a blue tag and asked her what it was for, since I'd never seen one. She told me it was to identify my donation as bound for SickKids, the Toronto children's hospital. What do I have to moan about, huh?
When you donate whole blood, gravity draws your donation from you, where your 2-unit bag of blood is rocked gently in a cradle on the floor to keep it from clotting.
When you donate with apheresis, the blood is drawn out using pressure. Trust me, this feels cool. It feels uncomfortable if the machine is set to draw more blood than your veins will allow. This is what happens in my case, so while my hematocrit (the amount of solids in blood) is high enough to say I should be done in about 40 minutes, my wee veins makes it go an hour.
You're sat in a loungey chair with a machine next to you which looks positively medieval. There are whirling wheels and multi-coloured tubes, resevoirs, and humming and clicking. Because your blood has to travel so far, a little bit of anti-coagulant is mixed in so it won't seize up. Like a lot of people, I have a reaction to that anti-coagulant. It makes my lips numb and I feel like my entire body is vibrating, like I was strapped to an outboard motor. To remedy this, the nurses make you chew some Tums. It's the calcium! This morning, I had yogurt and milk on cereal, so today my reaction wasn't as servere.
Finally, the ladies and one dude that work in at the apheresis clinic are awesome. Can you imagine trying to find a tiny tube in an opaque hunk of meat by poking it with a needle? That's what these people do for a living, and they're good at it!