Two cases of hyperkalemia after administration of hypertonic mannitol during craniotomy.

Mannitol is used commonly as an osmotic diuretic to reduce intracranial pressure during the perioperative period of craniotomy. The rapid administration of mannitol solution can cause an imbalance of electrolytes such as sodium and potassium. Here, we report two cases of mannitol-induced hyperkalemia. We demonstrate that administration of mannitol during craniotomy increases potassium iron concentration, and in some cases it may cause disturbance of cardiac function.