This patient has diabetic ketoacidosis (DKA) and a low serum potassium level, so potassium chloride should be administered. The patient should be making adequate urine before administration of potassium replacement. Low potassium stores in the body will need correction prior to initiation of insulin therapy to avoid cardiac arrhythmias. Potassium chloride should be added to each liter of intravenous fluids to maintain the serum potassium level in the 4.0 to 5.0 mEq/L (4.0-5.0 mmol/L) range with the continued use of intravenous insulin therapy.

Antibiotic therapy is not warranted at this time. The mild leukocytosis upon presentation is most likely related to stress from DKA rather than an infectious process. In addition, the chest radiograph is normal.

Sodium bicarbonate provides no added benefit when the arterial blood pH is greater than 6.9 and may be associated with harm. A 2011 systematic review found that bicarbonate administration worsened ketonemia. Several studies found higher potassium requirements in patients receiving bicarbonate. Studies in children found a possible association between bicarbonate therapy and cerebral edema.

During the treatment of DKA, initiation of insulin therapy and correction of acidosis will shift the extracellular potassium back into the intracellular space. Significant worsening of the hypokalemia noted at presentation could occur if this is not corrected to a serum potassium level higher than 3.3 mEq/L (3.3 mmol/L) prior to initiation of insulin therapy, which could lead to the development of arrhythmias. Insulin therapy can be safely initiated once the serum potassium level is greater than 3.3 mEq/L (3.3 mmol/L).