Can You Visit Someone In The Hospital During A Blood Transfusion? I've Tried Look Up If You Can Or Cannot And I Haven't Been Able To Find Anything. I Need This For A Book.

I would recommend trying to look at this book sold by Amazon :

https://www.amazon.com/Medical-Association-Providing-Consumer-Information/dp/144222570X

Also Medical colleges in your area might have books that they would let you borrow that would have the information that you need and some local libraries will help you and try to find if they can provide this information for you to borrow.