Is Blood supply here HIV/safe for surgery?

Having surgery soon in one of Shanghai large university hospitals.

First, should I have concerns about emergency doner blood they will will put aside for surgery (micro knee surgery)? I have a rather rare blood type B-, should I donate blood a head of time and can/do they store frozen blood like in States? Appreciate any advice/suggestions-Happy New Year!

No family here,only a few, rather new (but good) friends. Problem is my blood type, B-. In US less than 3% of population have that type, so might be problem finding donors who match, even if they are willing. There's always the type O's who are universal donors, but not sure about that compatibility since I am not only B, which is rare, but B- which is even rarer. I should have thought of this sooner cause you can only self-donate only one pint per month even if you're healthy...That's in States tho,don't know about here. Don't think there're a lot of routine blood loss w/this procedure since it's micro surgery, but will ask...It's just the emergency senerio I'm thinking about. It's certain I need to ask some questions fast and make sure Doc knows my blood type. Didn't think to before. Thanks for the input and welcome any other info or leads.. : )