A variety of failed approaches has led to skepticism regarding our ability to effectively prevent the injury causing CIN. Systemically administered vasodilators, such as dopamine agonists, adenosine antagonists, prostaglandins, and endothelin antagonists, have been disappointing despite the rationale behind their use [
13]. Antioxidants, such as N-acetylcysteine, ascorbic acid, and bicarbonate, have enjoyed initial enthusiasm based upon single-center trials [
14‐
16]. However, when considering data presented at society meetings and the increasing number of published negative trials, enthusiasm has waned and even meta-analyses have not found significant efficacy [
17]. It is in this context that the article by Meier
et al., published this month in
BMC Medicine [
4], is particularly valuable as it explores reasons for the heterogeneity in trial results.