An anion gap blood test gives a measurement of the acid-base balance (pH balance) in your blood. This lets you know whether your blood is too acidic or not acidic enough. The test also checks for an electrolyte imbalance in your blood. To do the measurement, an anion gap test uses the results of an electrolyte panel or other blood tests that measure your electrolytes.

The anion gap blood test shows whether your electrolytes are out of balance or if your blood is too acidic or not acidic enough. Too much acid in the blood is called acidosis . Too little acid in your blood is called alkalosis . Both conditions can be serious.

Source: MedlinePlus, U.S. National Library of Medicine