Abstract
BACKGROUND: Correction of "metabolic acidosis" by sodium bicarbonate is a common practice in intensive care unit or operating room. The physiological rationale underlying its use relies on the potential harmful hemodynamics effects of prolonged low extracellular pH. MAIN TEXT: Evidence showed that the "artificial" and transient correction of blood pH has little if any effect on intracellular pH, the variable of interest, which drives enzymatic reactions and metabolic pathways. Conversely, infusion of sodium bicarbonate corresponds to administer a sodium load which may affect patient's osmolarity thus cell functions. In this short comment, we recall the determinant of extra and intracellular pH, the lack of evidence regarding the clinical benefit of sodium bicarbonate infusion for metabolic acidosis, and the danger associated with acute change in blood osmolarity at the light of evolutionary biology. CONCLUSION: The physiological background to justify the use of SB for correcting metabolic acidosis in critically ill patients is thin if inexistent. This should be considered before initiating future trial.