Assessment of difference between calculated and measured blood hydrogen carbonate concentration by anion gap

Differences between calculated and measured hydrogen carbonate concentrations can pose a serious problem not only in monitoring severely ill patients, but also in those on hemodialysis. The purpose of this study was to investigate the possibility of estimation of differences between the calculated and measured hydrogen carbonate concentration by anion gap. The study included patients from regular hemodialysis program, and from Departments of Surgery, of Neurology and of Internal Medicine. Our results showed a 16% difference between measured and calculated hydrogen carbonate. Anion gap is a very useful parameter in assessing electrolyte disturbances. The discrepancy between the measured and calculated hydrogen carbonate concentration also increased with the rise in anion gap. Our results showed the possibility to determine the level of concentration difference by anion gap. This could be useful in situations such as metabolic acidosis, characterised by striking changes in electrolyte concentrations.