Point of care glucose (and potassium, if available)
VBG
Chem 7
Magnesium
Phosphorus
Serum ketones (or beta-OH and acetone)
Urinalysis
CBC
Urine pregnancy (if appropriate)
Consider infectious workup to identify trigger
Hyperglycemia (>200)
Acidosis
pH <=7.30 or bicarb <=15
+ketonemia (>1:2 serum dilution)
pH <=7.30 or bicarb <=15
Diabetic ketoacidosis 
Physiologic stress response 
Alcoholic ketoacidosis
Diabetes mellitus 
Starvation ketoacidosis
Nonketotic hyperglycemia
Cerebral edema in DKA
Hyperosmolar hyperglycemic state 