My father had open heart surgery (bypass and aortic valve replacement) on 30th July, he was discharged from the hospital on 9th August and seemed to be doing fine. Since 12th August he has fever and since two days he has frequent high fever upto 104 degrees. All his blood and urine examination and cultures are negative. Lot of the prescribed medications have been removed and now he is taking asprin, warfarin, metroprolol and levoflox only since two days. We have taken him to the doctors twice already due to high fever but the doctors are unable to explain the cause of his fever. His appetite is less (have to almost force feed him) and looks weak and feeble..but his pressure and pulse are within normal range...he has not reported any discomfort or pain ..for few days he had pain in arms (the doctors here said it might be thrombopheblitis but that too seems normal now and he has no pain or visible signs of inflammation)...Please advise i am worried....Anamika (from Nepal)