What lab work is required for Diabetic Ketoacidosis (DKA)?

From the Guidelines

Laboratory tests for diagnosing and monitoring diabetic ketoacidosis (DKA) should include blood glucose, serum ketones, arterial blood gases, electrolytes, complete blood count, and urinalysis, with specific measurement of b-hydroxybutyrate in blood being the preferred method for diagnosis and monitoring of DKA 1. When evaluating a patient for DKA, the following laboratory tests are essential:

• Blood glucose: typically >250 mg/dL
• Serum ketones: elevated, with specific measurement of b-hydroxybutyrate in blood being the preferred method 1
• Arterial blood gases: to assess for metabolic acidosis with pH <7.3 and bicarbonate <18 mEq/L
• Electrolytes: particularly potassium, sodium, chloride, and phosphate
• Complete blood count: to assess for infection
• Urinalysis: to detect ketones and glucose
• Anion gap calculation: to confirm metabolic acidosis, with values >12 mEq/L suggesting DKA It is crucial to monitor these parameters every 2-4 hours during treatment, as DKA results from insulin deficiency leading to hyperglycemia, ketone production, and metabolic acidosis, requiring prompt identification and treatment to prevent serious complications 1. The use of blood ketone determinations that rely on the nitroprusside reaction should not be used to monitor treatment of DKA, as they do not measure b-hydroxybutyrate, the strongest and most prevalent acid in DKA 1. Instead, direct measurement of ketones, such as b-hydroxybutyrate, may be necessary to monitor the resolution of the ketoacidosis 1.

From the Research

Lab Work for DKA

• The diagnosis of diabetic ketoacidosis (DKA) is characterized by a serum glucose level greater than 250 mg per dL, a pH less than 7.3, a serum bicarbonate level less than 18 mEq per L, an elevated serum ketone level, and dehydration 2.
• Laboratory tests used to diagnose DKA include measurement of A1C, blood urea nitrogen, creatinine, serum glucose, electrolytes, pH, and serum ketones; complete blood count; urinalysis; electrocardiography; and calculation of anion gap and osmolar gap 2.
• These laboratory tests can help differentiate DKA from other metabolic syndromes, such as hyperosmolar hyperglycemic state, gastroenteritis, and starvation ketosis, and can assist in diagnosing comorbid conditions 2.

Key Laboratory Parameters

• Serum glucose level: greater than 250 mg per dL 2
• pH: less than 7.3 2
• Serum bicarbonate level: less than 18 mEq per L 2
• Serum ketone level: elevated 2
• Electrolyte levels: require monitoring and replacement as needed 3, 4, 5

Monitoring and Management

• Frequent monitoring of patient's clinical and laboratory states is crucial in the management of DKA 5
• Laboratory tests should be used to guide fluid resuscitation, insulin therapy, and electrolyte replacement 4, 5
• Arterial or venous pH and blood gases should be monitored regularly 6