Nutritional and hemodynamic implications of large volumes paracentesis in cirrhotics.

Large volume paracentesis is a safe and widely diffused treatment of tense ascites in decompensated liver cirrhosis. Hemodynamic changes induced by this practice have been repeatedly indagated, but although some authors referred the lack of substantial modifications of plasma volumes after paracentesis, the administration of albumin or other plasma expanders is universally recommended to prevent complications as hyponatremia or renal insufficiency. On the other hand, hypoalbuminemia is one of the main features of nitrogen metabolism disturbances. Drawing ascites subtracts to the body an unknown amount of nitrogen because of its content in amino acids, which has never been documented. Because plasma amino acids imbalances have been involved in hepatic encephalopathy pathogenesis, which is a serious complications of cirrhosis potentially precipitated by paracentesis, our purpose was to document the amount of amino acids subtracted and to evaluate the possible modifications induced by paracentesis analyzing amino acidic patterns either in ascite or in plasma at the beginning and at the end of a large volume paracentesis (4 liters) in 20 ascitic patients. Paracentesis confirmed to be a safe practice, because it subtracts to body nitrogen no more than an amount of 3g of amino acids, and this is not followed by any modification of plasma patterns and ratios. In turn, these data allow a mathematical analysis of the relationship among osmolar and oncotic pressures in relationship to ascites and plasma volumes modifications.