I had a mixed bag of experiences when I had open brain surgery in 2004 - I was on Betaferon at the time - and I remember a nurse (who was trying to do the right thing) jamming the huge saline mixer needle deep, deep, deep into my thigh, and me later realising that the drug hadn't been mixed at all - it was just a huge saline injection.

They were determined to give me heparin/warfarin so I didn't get a blood clot - and my husband and I had to argue with that too - my platelet count was about 30k (normal is 150-500k) and I had been on mega-steroids to try and increase it in the two-weeks prior.

Still, I guess you can't expect them to know everything, every time - they work so hard and have so many constraints. Still, it could have been catastrophic.