Some Practical Aspects of the Measurement of Acid-Base Balance in Blood

ACID-BASE balance studies had their beginnings in 1908 when Henderson and Black ¹ reported studies on the bicarbonatecarbonic acid and phosphate buffer systems. In the same year Henderson constructed the equation which subsequently has formed the basis for investigations. In 1916 Hasselbalch employed Sorenson's term of pH in Henderson's equation and also indicated the dissociation constant by its negative logarithm. It has since been called the Henderson-Hasselbalch equation. At present, accurate and simple methods have been developed for pH measurement which coupled with other techniques permit a relatively complete mapping of acid-base disturbances.The measurement of pH (which represents the absolute hydrogen ion concentration) alone is insufficient in the clinical evaluation of hydrogen ion metabolism (acid-base balance). A serious disarrangement in hydrogen ion metabolism is compatible with a normal absolute concentration of hydrogen ions (normal pH). This paradox is explained by the compensatory mechanisms in the forms of the blood buffer