Aminoaciduria of severe trauma

Plasma and urine levels of free amino acids were measured in 15 severely traumatized adult patients while they were receiving fluids free of calories and nitrogen. Endogenous plasma clearance and the relative rates of reabsorption of free amino acids from renal tubules were calculated. These data were compared with similar studies of eight control subjects. Multiple injury provoked distinct patterns of free amino acids in plasma and urine. Hypoaminoacidemia and hyperaminoaciduria were seen in severe trauma. There was a marked depletion of nonessential amino acids in plasma of trauma victims. In contrast, the urinary loss of all amino acids was increased 5-10 times. This enhanced loss in patients, however, represented only 2.1% of total N excreted compared with 0.7% in control subjects. Considerable variations were seen in the selectivity with which various amino acids were reabsorbed by renal tubules. This may partly be due to the abnormal pattern of amino acids presented to renal tubules.