Salcido-Carmona CA, García-Rodríguez JA, Mercado-Botello J

Language: Spanish
References: 23
Page: 825-833
PDF size: 216.19 Kb.

ABSTRACT

The atomic structure is formed by electrons that surround the nucleus simulating a cloud, the latter composed of neutrons and protons. Neutrons have no charge, protons positive charge and electrons charge negative. An ion is defined as a particle that is charged, either, by loss or gain of an electron. The concept of anionic gap (AG) is based on the law of electrical neutrality: in an aqueous solution the number of cations must be equal to that of anions. The simplified formula AG = Na + -Cl--HCO3 - is used in case the serum potassium is in normal ranges, otherwise the formula will be AG = Na++K+-Cl--HCO3 -. The clinical utility of AG derives from the distinction between conditions that produce an acid-base disorder by the addition of an anion that causes an equivalent exchange in the main measurable ions in the extracellular environment (Na, Cl, HCO3), producing a calculation of normal AG; when the anion is not measured, the value increases. We must correct the AG in cases of hypoalbuminemia with the formula cAG: AG+[(4-serum albumin)x2.5], the serum decrease in albumin causes an ionic imbalance and as a result a compensatory decrease in sodium, altering the calculated AG.

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