[The influence of heparin and dilution of the results of blood gas analyses (author's transl)].

The results of blood gas analyses are affected by the type and length of storage of the sample and by differences in dilution and heparin concentration. Experiments established that keeping the specimen in iced water for one hour had no effect. Increasing the heparin concentration affected the results less than did dilution of the sample despite the acidity of the solution. If, on the other hand, heparin in powder form was employed (Monovette) the results were influenced by the absence of dilution of the sample and by the different type of heparin used. This particularly affected the acid-base balance and has to be taken into account when evaluating the results. The use of heparin Monovette simplifies the technique of taking blood samples as there is no need to fill the dead space and it provides reproducible results as the problem of differences in dilution does not arise.