Gnaden Huetten Memorial Hospital in Lehighton has opened the first floor of its newly constructed wing, an addition which adjoins a three-story building erected in 1967. Accomodations for 43 patients, including 16 new patient rooms, circle a centralized nursing station in a setting similar in design to an upper story which opened last month. Albert U. Koch, chairman of the board of directors, said that an enlarged Same Day Surgery unit, which will adjoin the operating room, is still under construction.