To help confirm a diagnosis of DKA and guide treatment, the physician may order laboratory measurements of:

• blood glucose
• blood bicarbonate
• blood urea nitrogen (BUN)
• hematocrit
• urine specific gravity
• blood osmolality
• white blood cell (WBC) count
• blood phosphate
• blood potassium and sodium
• pH.

The blood glucose level may range from 300 to 800 mg/dl. The blood bicarbonate level may drop below 15 mEq/L. Dehydration causes BUN levels,hematocrit, and urine specific gravity to rise. Blood osmolality may soar as high as 330 mOsm/L.

The WBC count may be high from hemoconcentration or infection. If the WBC count remains high after DKA has been treated, the patient probably has an infection. The blood phosphate level may be low. Blood potassium and sodium levels may be high, normal, or low, reflecting shifts between intracellular and extracellular fluid. The total body potassium generally is depleted. As ketones accumulate in the blood, the patient’s pH drops below 7.3.