in-patient - stationär behandelter Patient (or behandelte Patientin)

nursing service - Pflegeservice

aid - Hilfe

In British English, "aid" is "Hilfe" and "aide" (with an "e" on the end) is "Helfer".

However, in America the word "aid" (without an "e") is often used to mean "aide".

For this reason I am not sure, without context, whether this is a job title or a service offered.

See Google:
http://www.google.com/search?as_q=station�re Patienten&num=10&...
for several sites using precisely these terms and maybe giving you some additional information.

HTH