Klinik Sachsenhausen Hospital

Krankenhaus Sachsenhausen was a fantastic hospital. The floor was entirely dedicated to patients with stomach-related surgeries with an entire wing dedicated to bariatric patients. The staff all spoke English, although some were a little less fluent than I would have liked. I was able to get my needs across each time though.
Rooms generally have no more than two patients in them although you can pay a bit more for a private room. Gowns and towels are provided (which is a bit of a myth in Germany that they wouldn't be), and the nurses are quick to give you meds whether it be for pain, sleeping, or just to help pass a bowel movement. They've seen it all and are dedicated specifically to that floor so don't be embarrassed or afraid to ask!
Parking is extremely limited right outside the hospital but there is a parking garage about a block away which is relatively cheap for Frankfurt (20€ for 12+ hours). They say that your spouse cannot sleep in the room with you but if your roommate doesn't mind, they won't kick him/her out after visiting hours.

The staff I dealt with all spoke English, some better than others but at no time was I worried that I would not be taken care of properly because of a language barrier.