In a head injury patient, mannitol should not be used for control of increase intracranial pressure when

Ans. (a) Serum osmolality >320mOsmol/kgRef: Bailey 261 e p 318 Mannitol* Mannitol is widely used to reduce ICP* Commonly used preparation: 20% solution, 0.25-1gm/kg is given IV as bolus* Serum osmolality should not be allowed to go>320mOsm/L, to avoid systemic acidosis and renal failure.Uses of Mannitol* To reduce ICP or intraocular tension* To maintain GFR and urine flow in impending renal failure* Forced dieresis in hypnotic or other poisoning* To counteract low osmolality of plasma/ECF due to rapid hemodialysis or peritoneal dialysisContraindication of Mannitol* Acute tubular necrosis* Anuria* Pulmonary edema* Acute left ventricular failure* CHF* Cerebral hemorrhage