This is most likely a leadership problem of the unit more than anything else. People (yes, us included.) will do what we are allowed to get away with. Either the boss doesn't know this goes on and they need to be informed for it to change OR the boss does know and whatever crazy reason, lets it continue. If you wrote the details down go to the boss and show them the timeline. Even if you don't have the documentation go to the boss. They will ask, did you ask the NA/PCT again? Basically, you delegated-it didn't happen-how did you try to remedy the situation with NA/PCT- did you remind? Was the NA/PCT involved in a Code or something so major that the vitals could not be completed? I didn't think so. You will know if the boss took care of the situation if it changes if not then the NA/PCT is being insubordinate to the boss or the boss didn't really 'go there' when talking to the NA/PCT or the boss didn't even address at all. If so, talk to the boss when it happens again because it 100% will and then most likely nothing positive will come out of it and RN's will continue to be ignored and you may need to make the call on going up the chain of command. None of this is fun and I've been there in other industries that I've worked in.