Aims & Objectives: To evaluate outcomes of patients with sepsis and septic shock who receive fluids resuscitation with balanced and unbalanced solutions in middle-income country. Methods: An observational, analytical cohort study with propensity score matching in children admitted to pediatric critical care unit, who required fluid boluses due to hemodynamic instability within the first 48 hours after admission. Results: Out of the 1,074 admissions during the study period, 99 patients had sepsis and septic shock. Acute kidney injury was seen less frequently in children who received a balanced solution than in those who received an unbalanced solution (19.7% vs 24.6% p=0.006 ORa, 0.75; 95% CI, 0.65-0.87) adjusted for disease severity. In addition, the group who received balanced solutions had less need for CRRT (3.3 % vs 6.5%; p=0.02 ORa 0.48; 95% CI, 0.36-0.64) and stay at PICU (6 days RIQ 4.4-20.2 vs 10.2 days RIQ 4.7-26;p<0.001) than the group with unbalanced solutions. We found no difference in the frequency of metabolic acidosis (p=0.37), hyperchloremia (p=0.11) and mortality (p=0.25) between the two groups. Conclusions: In children with sepsis-associated organ dysfunction and septic shock, the use of unbalanced solutions for fluid resuscitation is associated with a higher frequency of acute kidney injury, a greater need for continuous renal support and more stay at PICU compared to the use of balanced solutions in middle-income countries.