The choice of drug for initial fluid therapy in the early postoperative period is important in terms of clinical efficacy and cost-effectiveness of the combination treatment.The aim of the study was to compare the effects of a succinate-containing solution and 0.9% NaCl solution when used as a drug of initial intravenous fluid therapy in early postoperative period in children.Materials and methods. A prospective randomized trial was conducted with participation of 43 patients having ASA II—III score after elective surgical interventions with a duration of 1-3 hours. In Group I («N») (n=23) the patients received continuous infusion of 0.9% NaCl solution in the early postoperative period (within 3 hours after the operation), in Group 2 («R») (n=20) continuous infusion of a succinate-containing solution was administered in 2.3 (1.6; 2.8) mode. The inter- and intragroup differences during the study were estimated by the changes of water-electrolyte and acid-base balance, basal metabolism, and phase angle (estimated integral index of cellular membranes condition) values. The data were recorded during the 5 stages of the study: 1 — immediately upon ICU admission (baseline), 2 — 60 minutes, 3 — 90 minutes, 4 — 120 minutes, 5 — 180 minutes after the ICU admission.Results. Significant differences in plasma potassium level between the groups 60 minutes (P=0.01) and 180 minutes (P=0.04) after the initiation of drugs infusion were found. In group N, at the 2nd stage, a 7% decrease in the potassium level was observed, while in group R, it increased by 2.1% as compared with the baseline. By the end of the study, potassium level decreased by 6.9% in group N and by 6.5% in group R. The intragroup differences were significant in Group N at the 2nd (P=0.02) and 5th (P=0.01) stages. In group R, no significant differences vs the baseline were found at any stage. In all cases, the values were within the reference values. In group N, at the 2nd stage the sodium concentration increased compared with the 1st stage by 2.1% (P=0.01). In group R, at the 5th stage, a significant decrease of Cl- concentration by 2.7% (P=0.01) was observed. The acid-base status showed a trend towards mixed acidosis at the 2nd stage in both groups, with the similarly significant pH reduction by 1.3% vs the baseline, whereas at 5th stage the decrease of pH was more significant in Group N (by 1.2% vs the baseline) than in Group R (by 0.9%) (P=0.01). In group N, the phase angle value was found to decrease by 8.6% at the 2nd stage and by 6% at the 5th stage (P=0.01). In group R no significant differences in the phase angle values were found.Conclusion. The succinate-containing solution has more favorable effect on the water-electrolyte and blood acid-base balance, as well as the state of cell membranes compared with the 0.9% NaCl solution.
