In 1948, Singer and Hastings introduced the concept of buffer base (BB). The change in BB from "normal" was called deltaBB (BB). This change in BB was an expression of the non-respiratory (metabolic) component of an acid-base disturbance. This was the first approximation to base excess.

In the 1950s, Astrup and coworkers (Copenhagen) developed the Astrup technique (equilibration technique), and in 1960 Siggaard-Andersen introduced base excess in blood as an indicator of the non-respiratory component of the acid-base status. The base excess curve was printed on the Siggaard-Andersen curve nomogram.

In 1963, Schwarts and Relman in Boston came with a critique of the new parameters, in particular base excess in blood. Later Siggaard-Andersen revised the concept and introduced base excess in extracellular fluid, also called standard base excess (SBE) or base excess in vivo.

In 1977, Severinghaus suggested a "detente" between the Boston and the Copenhagen schools. Severinghaus proposed a modified Siggaard-Andersen nomogram to permit one to estimate the chronic total compensation of hypercapnia, according to the Boston school's work. The Boston and Copenhagen schools remained "unreconciled" by the SBE correction. The two schools will continue to coexist!

In my point of view, base excess of the extracellular fluid will still be the key parameter to evaluate the metabolic component in acid-base disorders.

This is a historical review of the various base excess quantities.