The study was performed on eleven severely injured ventilated intensive care patients. Plasma and urine concentrations of free amino acids, nitrogen balance and energy expenditure were studied for a period of six days following trauma. Most of the free amino acids in plasma, especially the BCAA's return to reference range within a few days after trauma on administering the infusion solution investigated. An amino acid imbalance in the plasma of severely traumatized patients could be avoided by infusion of an amino acid solution containing only 10% branched-chain amino acids. The amino acids infused are utilized to an extent of more than 90%. However, a still markedly increased negative nitrogen balance, as well as a clearly negative energy balance indicate, that further investigations on nitrogen - and carbohydrate supply are necessary.
