In diabetic ketoacidosis, what is the primary cause of intracellular dehydration?

• A. Osmotic diuresis from hyperglycemia.
• B. Decreased insulin production.
• C. Elevated blood glucose level.
• D. Decreased serum osmolality.

Answer: (C)

When blood glucose rises dramatically in diabetic ketoacidosis, plasma osmolality increases. This creates an osmotic gradient that pulls water out of cells into the extracellular space to balance the forces, leading to intracellular dehydration. The high glucose level is the direct driver of this osmotic shift, making it the best explanation for why cells become dehydrated inside. Osmotic diuresis from the hyperglycemia contributes to overall fluid loss and volume depletion, but the intracellular water loss stems from the osmotic effect of the elevated glucose itself. Decreased serum osmolality would not cause this dehydration, since osmolality is increased, not decreased.