Hello Dr. My Mother Has CHF, Diabetes And High Blood

Hello Dr. My mother has CHF, diabetes and high blood pressure. For the past few months, her pressure has been low for example, 101/60. She also has been feeling hot, sweating, nauseous and ultimately vomiting 1 or more times a day. Also she has a very poor appetite. I have brought her to her primary doctor, cardiologist and gastroenterologist. They have run tests but do not find anything. Can you help me?