in metabolic acidosis: Unravelling the mystery.
Higher rates to the reference range indicate metabolic acidosis due to an increase in unmeasured anions
, especially the D-lactate, as occurs in lactic acidosis, determining the bicarbonate decrease (DeMORAIS & DiBARTOLA, 1993).
The difference between the concentration of unmeasured anions and cations can be estimated by calculating the AG representing the difference between the primary measured cations and the primary measured anions.
Elevated AG usually represents abnormal accumulation of either endogenous or exogenous unmeasured anions and indicates a primary disorder (a metabolic acidosis), regardless of the pH or the serum bicarbonate (HC[O.
When an acid (AH) accumulates in the blood, the hydrogen ion [H+] is buffered by HCO3- and the retained acid anion [A-] contributes to unmeasured anions
, raising the AG.
Strong ion gap: a methodology for exploring unmeasured anions.
Estimating unmeasured anions in critically ill patients: anion gap, base deficit and strong ion gap.
Unmeasured anions identified by the Fencl-Stewart method predict mortality better than base excess, anion gap and lactate in patients in the pediatric intensive care unit.
The anion gap is commonly used in clinical practice, especially in critically ill patients, as an approximation of the difference between the concentration of unmeasured anions
and unmeasured cations in plasma.
The SIG is superior to the anion gap for this purpose, since it retains sensitivity to unmeasured anions
despite fluctuating albumin and phosphate concentrations, simply because the [A.
An increase in the mean strong ion gap of > 10 mEq/l at bypass initiation (T2) signalled a surge of unmeasured anions.
In other words, unmeasured anions were still present but at reduced concentration.