Sodium bicarbonate therapy for metabolic acidosis in children stratified by acute kidney injury status and chloride levels: a retrospective cohort study.

Background: The efficacy of sodium bicarbonate in treating metabolic acidosis remains debated. Prior research indicated potential benefits for hyperchloremic patients and those with acute kidney injury (AKI). This study explored its effectiveness in children with or without AKI at diverse baseline chloride levels. Methods: A retrospective cohort of children with metabolic acidosis was selected from the Paediatric Intensive Care (PIC) database. Intensive care unit (ICU)-related data on diagnosis, laboratory tests, treatment, and outcomes were retrieved. Sub-grouping was done based on AKI status and baseline chloride levels. In-hospital and 28-day mortality were compared between children receiving and not receiving sodium bicarbonate, with adjustment for confounding factors. Results: Sodium bicarbonate therapy did not decrease in-hospital or 28-day mortality in overall AKI or in overall non-AKI children. Among stage 2-3 AKI [pediatric reference change value optimized for AKI (pROCK)] children, those on therapy had lower in-hospital (19.43% Conclusions: The association between sodium bicarbonate therapy and mortality in children with metabolic acidosis critically depends on baseline chloride levels. Its use was associated with increased mortality in those with hypochloremia (chloride <107 mmol/L) but reduced mortality in those with hyperchloremia (chloride ≥113 mmol/L), regardless of AKI status. Without considering baseline chloride, sodium bicarbonate therapy was not associated with a mortality benefit in patients with moderate to severe AKI.