<prompt> ECF volume assessment can be done most accurately bySucroseMannitolInulinAminopyrine  <response>: Indicators used for fluid volumes1. Total body water TBW- Deuterium Oxide D2O, Tritium oxide, Aminopyrine, Antipyrine2. ECF- Inulin, Sucrose, Mannitol, Sodium thiosulphate, Na223. Plasma volume- Evans blue, radioactive iodine labelled serum albumin I125 4. Blood cell volume- Cr51 labelled RBCThe most accurate indicator for ECF volume assessment is Inulin. 