Try this:
SHORTPAT: IIf(InStr([PATIENT],',')>0,UCase(Left(Left([PATIENT],InStr([PATIENT],',')-1),10)),UCase(Left([PATIENT],10)))
In Acc97, if you put, "SHORTPAT: UCase(Left(Left([PATIENT],InStr([PATIENT],',')-1),10))" into the Field row of the query design grid and [PATIENT] doesn't have a ","...