Abstract
We report a case of high serum osmolality, disturbed consciousness, congestive heart failure, acute renal failure and hyponatremia after administration of mannitol.
A 47-year-old man with a 5-year history of diabetes mellitus received an intravenous infusion of 4, 500ml of 20% mannitol for the treatment of acute glaucoma. He had disturbed consciousness and decreased urine volume after this treatment and was transferred to The Kitasato University Hospital on the 2nd day.
On admission, his consciousness level was confusion and stupor. He hadd wet, tense skin, but no pitting edema or decreased skin turgor. A chest X-ray showed obvious pulmonary congestion and cardiomegaly. Laboratory data showed a BUN of 44mg/dl, a serum creatinine of 6.6mg/dl, a serum sodium of 99mEq/l and a serum osmolality of 348mOsm/kgH2O. A high osmolar gap of 115mOsm/kgH2O was revealed from measured and calculated serum osmolalities. We suspect that intravenous mannitol infusion beyond the maximum excretion capacity of his diseased kidneys resulted in the accumulation of mannitol in the circulation. High serum osmolality induced the consciousness disturbance by intracellular fluid loss and the congestive heart failure by extracellular fluid excess. The acute renal failure superimposed on these conditions worsened his condition.
Two episodes of hemodialysis of short duration with a low blood flow (100ml/min) markedly improved his clinical condition immediately after treatment.
