[Metabolic acidosis].

Acid-base disorders due to different etiologies are frequently encountered in daily clinical practice and may result in life-threatening situations. Basic knowledge of the diagnostic and therapeutic approach of acid-base disorders is therefore essential for every clinician. Acid-base disorders should be treated according to their underlying etiology. Therefore, diagnosis of the underlying etiology is the critical step in the process of care for patients with acid-base disorders. Undirected buffering with HCO3 - should be avoided, since the application of HCO3 - might lead to severe side effects. A strict diagnostic pathway for the diagnosis of acid-base disorders is required, which should be vigorously applied:- analysis of the pH to classify acidemia or alkalemia- analysis of pCO2 and HCO3 - to classify the primary acid base disorder- analysis of the adequate regulation in order to detect additional acid-base disorders- analysis of the anion gap and the relationship of the anion gap vs. the change in HCO3 - to detect further metabolic disordersMetabolic acidosis can be divided into two main etiologies:- acidosis with addition of acid with increased anion gap,- acidosis with loss of HCO3 - with normal anion gap.