Positive impact of sodium L-lactate supplementation on blood acid-base status in preterm newborns

Abstract

Background: Preclinical studies indicate that lactate is a crucial cerebral energy substrate, with Na-L-lactate administration significantly reducing brain lesion volumes and improving motor and cognitive functions following neonatal hypoxia-ischemia in rat pups. Its neuroprotective effects are linked to neuronal metabolic utilization, making it a promising candidate for treating newborns with hypoxia-ischemia encephalopathy, a condition where hypothermia remains the only established therapy. However, before initiating a clinical trial, it is necessary to assess the effects of Na-L-lactate infusion on blood parameters.

Methods: We retrospectively analyzed blood parameters in 60 premature neonates during their first days of life. Among them, 30 received Na-L-lactate instead of Na-Cl to prevent hyperchloremic acidosis. Blood pH, lactatemia, bicarbonates, glycemia, natremia, chloremia, base excess, and hemoglobin were monitored before, during, and after Na-L-lactate infusion.

Results: Our findings showed that Na-L-lactate infusion lowered blood lactate levels while increasing pH from 7.25 to 7.31. After stopping the infusion, lactatemia was 1.9 mM, and pH reached 7.32. Na-L-lactate supplementation effectively restored normal blood pH, maintained natremia, and prevented hyperchloremia. Notably, even in cases of high initial lactatemia, lactate levels decreased during the infusion.

Conclusion: Our data are promising and emphasize the need for further research to explore its potential applications in neonatal clinical care.

Impact: Sodium L-lactate infusion does not increase blood lactate levels and restores normal pH in premature neonates. The study demonstrates that sodium L-lactate infusion avoids hyperchloremia while maintaining sodium levels, offering a potential alternative to sodium chloride. These findings highlight the need for additional research studies to further evaluate the safety, efficacy, and potential applications of sodium L-lactate infusion in neonatal care.

Fig. 1. Monitoring of blood lactate concentration and pH.

a Lactatemia of the cohort at birth. b Evolution of lactatemia after birth. Three different time windows after birth were determined: before, during, and after sodium L-lactate infusion. The same time periods after birth were used to analyze the data of the control group. c Evolution of blood pH after birth. Same time periods after birth than the one used in (b). *: p < 0.05, **: p < 0.01, ***: p < 0.001 and ****: p < 0.0001. ns not significant. Green square: data from patient number 29, who presented a major increase in lactatemia during and after the sodium L-lactate infusion, concomitantly with a hemodynamic deterioration in a context of septic shock at 3 ½ days of life. Data are presented as median and interquartile range.

Fig. 2. Monitoring of blood sodium and chloride concentrations.

a Evolution of natremia after birth. Three different time windows after birth were determined: before, during, and after sodium L-lactate infusion. The same time periods after birth were used to analyze the data of the control group. b Evolution of chloremia after birth (same time periods after birth than the one used in a). *Significantly different. *: p < 0.05, **: p < 0.01, ***: p < 0.001 and ****: p < 0.0001. ns: not significant. Data are presented as median and interquartile range.