A 68-year-old man presents with glucose 722 mg/dL and serum acetone 4+; an arterial blood gas is likely to show which feature?

A 68-year-old man presents with glucose 722 mg/dL and serum acetone 4+; an arterial blood gas is likely to show which feature?

• A. Low pH
• B. High pH
• C. Low PO2
• D. High PO2

Answer: (A)

Diabetic ketoacidosis from severe hyperglycemia with ketosis causes a metabolic acidosis with acidemia. Ketone bodies accumulate and lower the bicarbonate, driving the arterial pH down. On an arterial blood gas you would expect a low pH, with low bicarbonate and a compensatory drop in pCO2 from hyperventilation. Oxygen tension is typically normal unless there are other lung issues, so a high PO2 isn’t expected. So the most likely ABG feature is a low pH.

Diabetic ketoacidosis from severe hyperglycemia with ketosis causes a metabolic acidosis with acidemia. Ketone bodies accumulate and lower the bicarbonate, driving the arterial pH down. On an arterial blood gas you would expect a low pH, with low bicarbonate and a compensatory drop in pCO2 from hyperventilation. Oxygen tension is typically normal unless there are other lung issues, so a high PO2 isn’t expected. So the most likely ABG feature is a low pH.