This patient's clinical presentation is consistent with diabetic ketoacidosis (DKA). Mild cases of DKA with no vomiting can be managed by an experienced outpatient team or on a general inpatient ward. However, patients with severe DKA (eg, pH <7.1, bicarbonate <5 mEq/L, altered mental status) should be admitted to an intensive care unit for close monitoring as they are at greatest risk for complications (eg, cerebral edema).
Treatment of severe DKA begins with volume repletion with isotonic fluids (eg, normal saline, Ringer's lactate) given over an hour followed by initiation of an insulin drip. A small bolus given over an hour prior to initiating insulin therapy has been shown to minimize the risk of cerebral edema compared to starting an insulin drip immediately. Potassium-containing intravenous (IV) fluids should be administered simultaneously with the insulin drip for patients with normal or low potassium levels as insulin moves potassium intracellularly and causes hypokalemia.
Ongoing management consists of blood work every 1-2 hours and close titration of IV fluids to correct electrolyte derangements and acidosis. During this period, patients should be closely monitored for signs of cerebral edema such as altered mental status, lethargy, headache, and vomiting. A head CT should be ordered for patients in whom cerebral edema is suspected. Once the metabolic acidosis has resolved and the anion gap has closed, the patient can be transitioned to a subcutaneous insulin regimen.
Bicarbonate should not be added to the IV fluids as it has not been shown to be beneficial. In addition, bicarbonate administration can cause hypokalemia, cerebral edema, and metabolic alkalosis.
