Respiratory distress syndrome of the newborns is one of the most common critical states of the neonatal period, the cause of this complication is the primary deficiency of surfactant with the consequent progress of hypoxia, syndrome of fetal systemic inflammatory response and hypermetabolism. Goal of the trial: the evaluation of blood amino-acid metabolism in the newborns with respiratory distress syndrome depending on the duration of artificial pulmonary ventilation. Materials and methods: prospective controlled non-randomized one-centered trials with 48 newborns included. The main group (n = 22) included newborns to whom surfactant was administered one, and the control group (n = 26) included children who required the repeated administration of surfactant and continuous (72 hours and more) artificial pulmonary ventilation. Results of the trial. It has been found out that the children from the control group had higher concentration of citrulline in blood plasma (21.0 ± 0.7 versus 14.4 ± 1.2, p < 0.05) and lower concentration of the total protein in blood plasma (49.10 ± 0.87 versus 64.8 ± 1.8; p < 0.05). The negative correlation dependency was found between hypoproteinemia and content of alanine (r = -0.99; p < 0.05), arginine (r = -0.97; p < 0.005), citrulline (r = -0.93; p < 0.05) and tyrosine (r = -0.66; p < 0.05). Conclusion. Severe course of respiratory distress syndrome in the newborns is accompanied by obvious disorders in amino acid metabolism, which requires timely management
