Blas MJ, Nava MS

Language: Spanish
References: 20
Page: 193-195
PDF size: 52.89 Kb.

ABSTRACT

Introduction: Hypoalbuminaemia may confound interpretation of conventional acid-base parameters by underestimating the degree of metabolic acidosis.
Objective: To determine the influence of correction for hypoalbuminaemia on the diagnosis of raised anion-gap.
Design: Prospective study.
Setting: ICU of a general hospital of Durango, Durango; Mexico.
Methods: Arterial blood samples of 69 critically ill patients of an intensive care unit were analyzed using a standard blood gas analyzer anion gap was calculated (sodium + potasium) - (chloride + bicarbonate) and then corrected for albumin using Figge´s formula.
Results: The incidence of admission hypoalbuminaemia was 57%, after correction of albumin the incidence of a raised anion gap (18 mmol) increase from 28% to 44%. Correction produced an average increase in the AG 5.7 mmol (bias) with limits of agreement of 13.7 and- 27.2 mmol (Altman-Bland method).
Conclusion: Metabolic acidosis from unmeasured ions in critically ill patients maybe more frequent that often recognized. The albumin adjusted anion gap is a reliable and easily applicable alternative, which can be recommend for clinical use.

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