[Standardisation of obtaining blood samples: influence of tourniquet application on 33 constituents of blood and serum (author's transl)].

The extent and dynamics of changes by short (1 min) or prolonged (6 min) tourniquet application while obtaining venous blood samples were analysed with respect ot 33 frequently measured constituents of blood and serum. After 6-minute tourniquet application the values for red cells, haemoglobin, packed cell volume, total protein, albumen, gamma-glutamyl transferase, alkaline phosphatase, lactate dehydrogenase, creatinekinase, bilirubin, cholesterol, total glycerol and calcium increased by an average of 4-9%. One-minute tourniquet application did not have a significant effect. Levels of sodium, potassium, carbon dioxide, creatinine, uric acid, ratio of electrophoretic fractions and the MCV, MCH and MCHC indices were not affected even by 6-minute tourniquet applications. The introduction of blood sampling under standardised conditions is proposed.