Fluid management in the intensive care unit Saline vs. balanced solution

Volume management is an essential component of intensive care medicine. In addition to the estimation of the amount of fluid needed by a critically ill patient with the options of pharmaceutical and instrumental volume management, the question of the suitable substitution solution for volume treatment triggered a lively discussion in the last decade. For this purpose, crystalloid and colloidal substitution solutions are available. The use of colloidal solutions is associated with an elevated risk for acute kidney injury and with an increased mortality, so that substitution with crystalloid solutions has become established as the clinical standard. Various isotonic formulations are available for this purpose. In 2012 an Australian open-label study provided evidence that the substitution of a balanced chloride-reduced crystalloid solution in an intensive medical care situation was superior to a physiological saline solution with respect to the incidence of acute kidney injury. The potential reasons were presumed to be the formation of a hyperchloremic acidosis and vasoconstriction of the vas afferens by the supraphysiological chloride concentration in 0.9% saline. More recent high-ranking published data now question these findings and provide the opportunity to re-evaluate the currently available evidence.