I think it depends. I am not a nurse (yet) but I have worked as a PCNA (patient care nursing assistant...basically a glorified NA) and I currently work as a nurse tech. For my PCNA job, I met with the manager first, took a tour of the unit and everything...then I met with HR afterwards to complete all of the paperwork and everything.
For my nurse tech job, however, I interviewed with HR first (just a basic general interview and also to tell them what areas of nursing interest me the most) and then had to wait a couple of weeks before I interviewed with my unit manager.
Either way I hope it works out for you. Good luck!