Doing my every-other-Saturday-morning gig

I’m sitting/lying in a chair at the blood bank, hooked to an apheresis machine.  I’ve been a semi-regular whole-blood donor for years, but earlier this year I started doing apheresis, which is a centrifuged platelet donation, when I found I could donate every ten days, as opposed to whole-blood donation, which I can only do once every eight weeks.  And since platelet units count the same as whole blood, I build up credits much faster.  Ten days isn’t a very convenient interval, though, so I arrange to come in every other Saturday morning.

Apheresis used to be a Big-Deal donation, requiring needles in both arms: one for pulling out the whole blood to be centrifuged, and the other for returning the “used” blood.  The donor was crucified on the couch, both arms immobile for the hour or so it took to do the procedure.  It was, frankly, a big nuisance to sit through.  That changed in the 1990s, when a single-needle pheresis machine was developed, with draw and return pipes coming through a manifold to the needle.  That change is what lets me sit here typing while the pheresis machine works, and makes it little more complex for me than a whole-blood donation, except for taking longer to do.

The most annoying effect is that the anti-coagulant used in the return solution binds to calcium in the blood, which causes minor neurological effects in tissue with lots of nerve endings—in short, my lips tingle and I get a strange metallic taste in my mouth.  Sucking on antacids like Rolaids or Tums helps, and the effects go away as soon as I’m disconnected.