or, if you prefer, "blood electrolytes," although in medical usage these two terms are equivalent. -- "Blood ionogram" is a false cognate often seen in literal translations of medical documentation into English. Although the term "ionogram" has specific meanings in other fields, particular with regard to the measurement of ionizing radiation (i.e., radioactivity), It's virtually never used per se in English in connection with blood tests or blood chemistry. For reference, here's what the former U.S. Surgeon General's encyclopedic online dictionary has to say (this about the Chem-20 blood test): -- " Electrolytes: Positively charged ions include sodium, potassium, calcium, and magnesium… Negatively charged ions include chloride, bicarbonate), protein, phosphorous, SO4, and organic acids. When an electrolyte test is performed, the measured ions usually include sodium, potassium, chloride, and bicarbonate. Calcium and magnesium levels are also obtained in many institutions as part of this test." -- Hope this helps!