Cover letter...do you always mention the hiring manager?

Hi everyone!! I have an interview tomorrow and well with all the excitement I forgot to ask the recruiter the managers name. I guess I could call her, but she also said there is new management, so I am not sure who will be interviewing. The recruiter told me to just say I was there for an interview in the unit. My question is if I start my cover letter with

Dear ICU Staff/ Hiring Manager

or is that too unprofessional?

Thank you for any help

[McBambi]

You can start it off with To whom it may concern

[avaloncar, BSN, RN]

Congrats on your interview! As the other poster said. Just write "To Whom it May Concern". Good luck!