What electrolyte abnormality is commonly seen in patients with diabetic ketoacidosis?

In diabetic ketoacidosis (DKA), hyperkalemia is a common electrolyte abnormality. This occurs due to several factors associated with the acidotic state of DKA. When ketoacids accumulate in the blood, it leads to an increase in hydrogen ions (H+) in the extracellular fluid. In response to this acidosis, potassium ions (K+) will shift out of the cells into the extracellular space to help mitigate the effects of increased hydrogen ions. This intracellular shift results in elevated serum potassium levels, leading to hyperkalemia.

It's important to note that while patients may present with high potassium levels during the initial evaluation, total body potassium is often actually depleted because of factors such as vomiting, osmotic diuresis, and loss of potassium in urine due to the associated hyperglycemia. Therefore, the serum potassium may appear high, but the patient could still be at risk for hypokalemia with rehydration and insulin therapy, which would drive potassium back into the cells.

Understanding this mechanism clarifies why hyperkalemia is commonly seen in DKA, as the primary physiological response involves a compensatory shift of potassium due to acidosis.