Determination of the plasma anion gap (AG) is an important step in approaching the differential diagnosis of metabolic acidosis
The "real" balance is given by the equation:
[Na] + [other cations] = [Cl] + [HCO3] + [other anions]
[Na] - ([Cl] + [HCO3]) = [other anions] - [other cations] = "Anion Gap"
- 12-16 mEq/L
Elevated anion gap 編輯
- Lactic acidosis, usually due to marked systemic hypoperfusion or to malignancy.
- Ketoacidosis due to diabetes mellitus, alcohol, or fasting, in which ??-hydroxybutyrate is the primary unmeasured anion.
- Most patients with renal failure
- Ingestions, in which the major retained anions are formate with methanol, glycolate and oxalate with ethylene glycol, and ketones and lactate with aspirin.
High Anion Gap Metabolic Acidosis 鑑別診斷編輯
- diabetic ketoacidosis
- lactic acidosis
- ethylene glycol
Normal Anion Gap Metabolic Acidosis 鑑別診斷=編輯