Pharmacokinetic Evaluation of a New Maintenance Solution for Severely Injured Patients

Nine severely injured patients (SIP) and 9 healthy controls received 20 min iv infusions of Aminoplasmal-LS-10 (2.15 ml/kg body wt containing 0.215 g amino acids). Employing the values of the plasma amino acid (AA) concentrations 3, 7, 15, 30, 45, 70, and 150 min after the end of the infusion, we calculated the elimination half-life (t_1/2), the elimination constant (k₂), the total clearance (Cl_tot), and the transfer of the individual AA. The AA showed t_1/2 between 6 (Glu) and 23 (Thr) min. Comparing the metabolic kinetics of healthy controls and SIP, there were no statistical differences in t_1/2 or in k_2. In the SIP, nearly all plasma AA showed increased transfer and Cl_tot, significantly for Thr (p < 0.05), Pro, Gly, Ala, Arg (p < 0.02), Glu (p < 0.01), and Met (p < 0.005). In contrast, the Cl_tot for Phe and Tyr were decreased. Except for Phe, Tyr, Met (enhanced values) and Arg (no change), the fasting values of AA concentrations in the SIP were diminished compared to those in the healthy controls. Based on the measured transfer, we have developed a new maintenance solution adapted to SIP. Compared with Aminoplasmal, it is necessary to apply AA concentations which are increased in Lys, His, Phe, Tyr, Val, Ala, and Ser, and reduced in Arg, Pro, Leu, Ile, and Gly.