Schwere Azidose: Differenzialdiagnostik und Therapie [Severe acidosis: differential diagnostics and treatment]

The extracellular H(+) ion concentration in the human body is adjusted within close limits to 40 ± 0.3 nmol/l in blood to ensure maintenance of normal cellular and extracellular homeostasis. The carbonic acid-bicarbonate buffer system is the major regulator of acid-base homeostasis and is readily accessible for the clinician through determination of pH, pCO(2) and HCO3(–). Acidosis is primarily a respiratory or metabolic disorder causing acidemia (H(+) >43 nmol/l or pH <7.37). Severe acidosis (H(+) >60 nmol/l or pH <7.2) needs to be diagnosed rapidly and treated according to the underlying condition. A systematic approach with simple bedside diagnostic tools helps to characterize the underlying acid-base disorder, to identify the etiology and to initiate the appropriate causal treatment.