Hi, Excess fluid is usually lymphatic in nature and can be due to a number of processes such as congestive heart failure, hepatic portal hypertension resulting in liver congestion and fluid backup, pneumonia, and kidney disease. Fluid is diuresis according to the clinical picture of the patient and discretion of the physician. Fluid loss in this manner usually doesn t contain critical nutritional elements although some electrolytes such as potassium can be especially lost and are usually replaced as diuresis occurs. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Dariush Saghafi, Neurologist