Q: All of the following can be used in monitoring of Diabetic Ketoacidosis (DKA) except? 

A) hourly glucose measurement 
B) periodic venous pH
C) direct measurement of beta-hydroxybutyrate 
D) serum anion gap
E)  nitroprusside testing



Answer:  E

DKA requires very close monitoring of metabolic status which includes every hour glucose measurement (correction neither too slow nor too fast!) as well as closing of anion gap. Arterial ABGs are not required as periodic venous ABGs should be enough to guide resolution of acidosis. Also, periodic direct measurement of beta-hydroxybutyrate guides resolution of DKA. Nitroprusside testing has been used in monitoring of DKA but its not a reliable method as it reacts with acetoacetate and acetone. Acetone is biochemically neutral and does not contribute to the ketoacidosis. 



Reference:

Savage MW, Dhatariya KK, Kilvert A, et al. Joint British Diabetes Societies guideline for the management of diabetic ketoacidosis. Diabet Med 2011; 28:508.