<prompt> Mannitol is not useful for ?GlaucomaRaised ICTImpending renal failurePulmonary edema  <response>: Ans. is d i.e., Pulmonary edema Mannitol It is a nonelectrolyte of low molecular weight that is pharmacologically ine. It raises osmolarity of plasma and tubular fluid. Mannitol decreases tubular water and electrolyte reabsorption by ? Due to osmotic effect, fluid is retained in the lumen of PT. Inhibits transpo processes in thick AscL1 - most impoant cause of diuresis. Expands ECF r intravascular volume - draws water from the intracellular compament - increases GFR and inhibits renin release. Increases renal blood flow, especially to medulla -3 medullary hypeonicity is reduced - coicomedullary osmotic gradient is dissipated - passive salt reabsoion is reduced. Uses - Raised IOT glaucoma, raised ICT, to maintain. GFR and urine flow in impending renal failure, and to counteract low osmolality of plasmaECF due to rapid hemodialysis. Contraindications - Acute tubular necrosis ARF, anuria, pulmonary edema, Acute LVF, cerebral hemorrhage. 