In the acid-base status of DKA, what is the expected carbon dioxide (CO2) level?

In diabetic ketoacidosis (DKA), the body experiences a significant metabolic disturbance primarily characterized by the accumulation of ketone bodies, leading to metabolic acidosis. This condition typically presents with a low arterial blood pH, primarily because of increased acidity due to the buildup of ketoacids.

As metabolic acidosis develops, the body attempts to compensate for the reduced pH by increasing the rate and depth of respiration. This response, known as Kussmaul breathing, enhances the elimination of carbon dioxide (CO2) through hyperventilation. Consequently, the expected CO2 levels in DKA are typically low, reflecting the respiratory compensation for the metabolic acidosis.

Therefore, the low CO2 level indicates that the respiratory system is responding to the acidotic state by attempting to reduce CO2, which in turn helps to increase pH back towards normal. This physiological response is a hallmark of metabolic acidosis due to DKA, resulting in the observed low CO2 levels.