A young girl with T1DM presents with drowsiness and deep breathing and a blood sugar level of 20. What is the next appropriate step in her management?

In a case where a young girl with Type 1 Diabetes Mellitus (T1DM) presents with symptoms of drowsiness and deep breathing, accompanied by a significantly elevated blood sugar level, the clinical picture is suggestive of diabetic ketoacidosis (DKA). Deep breathing is indicative of the Kussmaul respiration that often accompanies metabolic acidosis, which is common in DKA.

To properly manage this condition, obtaining an arterial blood gas (ABG) is crucial. The ABG will provide key information about the patient’s acid-base status, including the level of acidosis or alkalosis and the presence of compensatory respiratory changes. This information helps guide the immediate treatment plan, which could include administration of intravenous fluids, insulin therapy, and electrolyte management.

Other options, such as serum urea and blood culture, while important in their own right, are not immediate priorities in this context. A CT scan is not relevant to the acute management of DKA and would not provide useful information for addressing the current crisis. Therefore, performing an ABG is the most appropriate next step in assessing and managing the girl’s condition effectively.