TOTAL PARENTERAL ALIMENTATION (TPA) IN THE NEWBORN: METABOLIC ALKALOSIS RESULTING FROM THE ADMINISTRATION OF AN EXCESS OF ANIONIC AMINO-ACIDS (a.aa.)

Abstract

36 newborns (28 weighing < 2500 g) were given TPA because of extreme prematurity, apnoeic spells, HDS, or feeding difficulties. Owing to the composition of the commercial amino-acid mixture used for TPA, the full TPA. regimen included the administration of an excess of a.aa. (aspartic+ glutamic ac.= 5.1 mmoles/kg/day) over cationic aa. (lysine+hystidine + arginine= 2.6 mmoles/kg/day), and an excess (of 4.0 mEq/kg/day) of fixed cations (mostly Na+) over fixed anions. After a few days of TPA, hyperbasemia developed in most patients. These results show that TPA with an excess of a.aa. is able to produce a negative metabolic H+ balance, and are in keeping with observations of Heird et al (New Engl J Hed, 287; 943, 1972), showing that TPA with an excess of cationic aa. results in metabolic acidosis. Other pertinent clinical and laboratory findings will also be presented.