Not really sure if this helps but managed to find these tests that seem to be mentioned by a few different sources
Arterial or venous blood gas analysis
Serum electrolytes
Urine pH
An arterial blood gas analysis or serum electrolytes test, such as a basic metabolic panel, will confirm that acidosis is present and indicate whether it is metabolic acidosis or respiratory acidosis. Other tests may be needed to determine the cause of the acidosis.
This site seems to have a lot of information on the subject