Intravenous sodium and chloride: not too much, not too quick, and only to healthy kidneys!

Although the first clinical use of a fluid therapy based on sodium chloride dates back to the European cholera pandemic in 1831 (1), the first clinical study focused on the acid-base equilibrium in patients receiving NaCl 0.9% (or saline or normal saline) for volume expansion was published in 1999 and was entitled “Rapid Saline Infusion Produces Hyperchloremic Acidosis in Patients Undergoing Gynecologic Surgery” (2). This landmark study aimed at evaluating the effects of the administration of saline, a high chloride concentration crystalloid, in clinical practice.