Electrolyte Blood Press.  2010 Dec;8(2):66-71.

Acid-Base Disorders in ICU Patients

• Oh YK

Abstract

Metabolic acid-base disorders are comnom clinical problems in ICU patients. Arterial blood gas analysis and anion gap (AG) are important laboratory data in approaching acid-base interpretation. When measuring the AG, several factors such as albumin have influence on unmeasured anions and unmeasured cations. If a patient has hypoalbuminemia, the AG should be adjusted according to the albumin level. High AG metabolic acidoses including lactic acidosis, ketoacidosis, and ingestion of toxic alcohols are common in ICU patients. The treatment target of lactic acidosis and ketoacidosis is not the acidosis, but the underlying condition causing acidosis. Gastric acid loss, diuretics, volume depletion, renal compensation for respiratory acidosis, hypokalemia, and mineralocorticoid excess are common causes of metaboic alkalosis. In chloride responsive metaboic alkalosis, volume and potassium repletion are mandatory.

Keyword

anion gap; metabolic aidosis; metabolic alkalosis; lactic acidosis; ketoacidosis

MeSH Terms

Acid-Base Equilibrium
Acidosis
Acidosis, Lactic
Acidosis, Respiratory
Alcohols
Alkalosis
Anions
Blood Gas Analysis
Cations
Compensation and Redress
Diuretics
Eating
Gastric Acid
Humans
Hypoalbuminemia
Hypokalemia
Ketosis
Potassium
Alcohols
Anions
Cations
Diuretics
Potassium

Figure

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  Fig. 1 The pH in Arterial and Venous Blood during Cardiopulmonary Resuscitation.*Modified from the study of Weil MH et al. Ref. 5.

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  Fig. 2 Metabolism of Glucose and Lactate.

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  Fig. 3 Metabolism of Ketones. CNS, central nervous system.

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