Medic terms

Hi! I have to translate an article to Spanish, it's about Decontamination and Sterilization. I have some problems with abbreviations and some terms so I'd like to see if somebody can help me even if the meaning of the word is given to me in English. First, What's the meaning of RN ? I'll give you the context: "If you use RN staff or surgical technicians to process instruments, oyour expenses will be higher tahn...". I imagine it's a kind of technician, I'm not sure but it's not Royal Navy for sure.

Then, what about Cannulated? It says here "cannulated drill bit"

Ok, Well, more doubts may appear during the translation so probably I'll continue asking for help

Thanks a lot!!!

PS: Is there a good site where I can find  medical vocabulary? 

Thanks a lot Francesca!!

Another doubt: Autoclaved blood

autoclave   means : a piece of equipment that uses steam at high pressure to sterilize objects used in medical operations

But I odn't understand the meaning as an adjective

Hello again!!

Another doubt: what's the meaning of Payors?

Thanks a lot!