Friday June 20, 2008
CORRECTING ANION-GAP FOR ALBUMIN

Hypoalbuminaemia is common in critically ill patients with shock. Fail to consider this component, may associated with a low or normal observed anion gap despite clinically significant amounts of lactate and other occult tissue anions. Ideally, albumin corrected anion gap should be used.

Correcting the ANION-GAP for changes in albumin would be a better predictor of mortality than an uncorrected ANION-GAP.

The measured ANION-GAP is corrected for changes (usually decreases) in albumin by using following simple formula


adjusted AG = observed AG + 0.25 x ([normal albumin]-[observed albumin])

AG = Anion Gap



Reference: click to get abstract

Anion gap and hypoalbuminemia. Critical Care Medicine. 26(11):1807-1810, November 1998