[Blood picture in lactate acidosis. Part 2: acid-base equilibrium and lactate]

A differentiation between lactate emia (lactic acid emia) and lactate acidosis (lactic acidosis) is made. The normal value for blood lactate concentration is 1-2 mmol/1. The term lactate emia is used for lactate values between 2-6 mmol/1. The limiting value for the diagnosis of lactate acidosis should be more than 7-8 mmol/1 for the blood lactate concentration. Furthermore the different buffer mechanisms are evaluated in respect to their influence on the pH of the blood and to lactate metabolism. Especially the mechanism of respiratory compensation for metabolic acidosis is discussed. It is stated that for the diagnosis of lactate acidosis the blood-pH and the bicarbonate concentration should be measured.