Chemistry
Serum osm
Lactate
Serum ketones
CBC
Also consider:
Blood cultures
Urinalysis/Urine culture
LFTs
Lipase
Troponin
CXR
ECG
Head CT
Blood cultures
Urinalysis/Urine culture
LFTs
Lipase
Troponin
CXR
ECG
Head CT
Glucose >600
Osm >320
Bicarb >15
pH >7.3
Serum ketones negative or mildly positive
Neurologic abnormalities frequently present (coma in 25-50% of cases)
Hyperosmolar hyperglycemic state
Physiologic stress response 
Cerebral edema in DKA
Diabetes mellitus 
Nonketotic hyperglycemia
Diabetic ketoacidosis
Hyperosmolar hyperglycemic state 
Diabetic ketoacidosis 