The other big company in our office building hosted a blood drive today. I missed the one that our company hosted a few weeks ago so I hydrated up and went. I’m a good candidate for apheresis and my iron was good, so they hooked me up. After the initial “this bit is for blood tests” vials the machine started in, but very shortly the BP cuff released and I soon felt a pinch in the arm. Turns out the machine glitched out! They stopped it and sent me away, but still let me have cookies.
I had a bad experience with that machine once years ago, where the plasma flush back was not properly going into my vein, and just built up as a bubble in my arm. When I yelled for help I was ignored for at least a minute, they were busy and distracted. This time I went “Ow!” and he dropped everything, hit pause on the machine, went back to what he’d been in the middle of, then returned to diagnose. They can’t restart you on another machine or they will take more blood than is recommended.