Method for measuring acidosis

A reliable assessment of the acid-base status is not possible by the measurement of the pH of the urine! This is because, on the one hand, the pH value of the urine naturally ranges between pH 5 and 8 depending on nutrition and, on the other hand, only 1% of acid is released as free acid that can be tested by test-strips. A large part of the acid occurs in the urine as ammonium compounds that are not captured by test-strips.

Measurement of the pH value only make sense if the pH of the urine is measured regularly and often during the day at short time intervals. Additionally meals have to be equal every day and a normal kidney function is required Only under these conditions the measurement with pH strips can give a hint towards acid-base status.

Alternative method:measuring net acid excretion

Measurement of the net acid excretion within one day gives you an exact statement about the acid-base status. The analysis of the 24-h-collected urin of relevant excretion products enables the measurement of the net acid excretion.

Technique of Friedrich Sander (pH value of urine)

This technique, developed in the 1930s, is still applied today: in addition to the pH-value of the urine, the buffer capacity of the urine is determined with five measurements spread over the course of the day. Expert interpretation is necessary for this method of measuring the pH value.

Technique of Jörgensen and Stirum (not a pH value of the urine)

This determines the buffering capacity of the blood. Statements about the buffering capacity of red blood cells and hence about the possible degree of acidosis within the cells are possible. This special blood analysis is undertaken by specialised laboratories.

Basica Acid-Base Calculator