Determinants of blood pH in health and disease

Crit Care. 2000;4(1):6-14. doi: 10.1186/cc644. Epub 2000 Jan 24.


An advanced understanding of acid-base physiology is as central to the practice of critical care medicine, as are an understanding of cardiac and pulmonary physiology. Intensivists spend much of their time managing problems related to fluids, electrolytes, and blood pH. Recent advances in the understanding of acid-base physiology have occurred as the result of the application of basic physical-chemical principles of aqueous solutions to blood plasma. This analysis has revealed three independent variables that regulate pH in blood plasma. These variables are carbon dioxide, relative electrolyte concentrations, and total weak acid concentrations. All changes in blood pH, in health and in disease, occur through changes in these three variables. Clinical implications for these findings are also discussed.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Acid-Base Equilibrium / physiology*
  • Acidosis / diagnosis*
  • Alkalosis / diagnosis*
  • Blood Gas Analysis
  • Cardiovascular Physiological Phenomena
  • Critical Care / methods
  • Critical Illness*
  • Female
  • Humans
  • Hydrogen-Ion Concentration
  • Male
  • Prognosis
  • Reference Values
  • Respiratory Physiological Phenomena
  • Sensitivity and Specificity
  • Water-Electrolyte Balance / physiology*