urine electrolyte analysis urine sodium analysis true https://www.ncbi.nlm.nih.gov/pubmed/31911412 urine sodium ion analysis JSmith A method which assesses the amount, proportions or properties of sodium in urine, the fluid waste product excreted by the kidneys. Sodium, the chemical element with atomic number 11 that in its ionic form has lost one electron, forming a cation with a charge of +1, is the chief cation of extracellular body fluids. urine Na+ analysis 2013-11-13T11:19:45Z MMO:0000434 measurement_method_ontology