Electrolyte Blood Press.  2006 Mar;4(1):44-46. 10.5049/EBP.2006.4.1.44.

Clinical Usefulness of the Serum Anion Gap

• Lee S
• Kang KP
• Kang SK

• KMID: 2052268
• DOI: http://doi.org/10.5049/EBP.2006.4.1.44

Abstract

The anion gap in the serum is useful in the interpretation of acid-base disorders and in the diagnosis of other conditions. In the early 1980s, ion-selective electrodes for specific ionic species were introduced for the measurement of serum electrolytes. This new method has caused a shift of the anion gap from 12+/-4 mEq/L down 6+/-3 mEq/L. It is worthy for clinicians to understand the range of normal anion gap and the measuring methods for serum sodium and chloride in the laboratories that support their practice. While an increase in the anion gap is almost always caused by retained unmeasured anions, a decrease in the anion gap can be generated by multiple mechanisms.

MeSH Terms

Acid-Base Equilibrium*
Anions
Diagnosis
Electrolytes
Ion-Selective Electrodes
Sodium
Anions
Electrolytes
Sodium

Figure

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  Fig. 1 Anatomy of the serum anion gap.

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