Lung Cancer / Pneumonia / Fluid on Lungs

My Mother is 76 and was diagnosed stage IIIB Non-Small Cell Lung Cancer April 2008, 19 months ago. She went through radiation and chemo went into remission and after six months of remission cancer activity showed up on her PET Scan. She went through another round of chemo this past summer and in the last month her health is really failing. She became unable to swallow liquids very well and her left vocal cords became paralyzed. She developed pneumonia recently and was in the hospital for a bit and was prescribed antibiotics. She started developing something called Sundowners Syndrome where she became very delusional. The doctors felt it best to send her home to recuperate. She is unable to walk by herself and she tried to walk by herself, fell and broke her hip. She is back in the hospital and they want to operate but feel she is too weak to do the surgery. They said she would probably die on the table. The doctors are saying that her situation is very grave and not a whole lot can be done to improve her. She has to have the surgery, so the surgery has been rescheduled for this Monday--but in the meantime while in the hospital they had to take her off the fluid bags because her lungs are filling up and they are having to drain them. She is in and out of it with the pain meds. Is this normal? Is there anything that can be done? Thank You in advance.