Sodium bicarbonate infusion for prevention of acute kidney injury: no evidence for superior benefit, but risk for harm?

The best "treatment" of acute kidney injury (AKI) is prevention. Patients who are at high risk of AKI should have an assessment of their volume status and receive appropriate volume expansion. The most effective type of intravenous fluid remains unclear. Innumerable studies have compared sodium bicarbonate and isotonic saline and have combined fluid hydration with pharmacological interventions, particularly N-acetyl-cysteine. However, abundant systematic reviews and meta-analyses have provided conflicting conclusions and have recognized a significant degree of heterogeneity between studies and publication bias. Most studies comparing intravenous sodium bicarbonate and saline were small. They often enrolled patients with a low risk for AKI, yielding low serious events (renal replacement therapy), and used different protocols for administration of fluids. Based on current literature, intravenous sodium bicarbonate does not seem to be more efficient than saline for the prevention of contrast-media-induced AKI, cardiac surgery-associated AKI, pigment nephropathy or septic AKI. However, some cohort studies or prospective randomized trials did track and report serious adverse events, such as higher rates of AKI or higher in-hospital mortality. At present, it should be concluded that the use of intravenous sodium bicarbonate administration to prevent AKI should be evaluated further in multicenter randomized double-blind trials rather than adopted into routine clinical practice.