I had total knee replacement 3 weeks ago. I am progressing fine but I have night sweats every night since the surgery. I take Norco for pain, mostly at night before bed. Is the general anesthesia still in my system and can it cause night sweats? I have also been anemic post surgery. Why do u think I am having these sweats? I am 60 yrs old, post menopausal with no symptoms until the knee surgery.