Theadministrationofi.v.fluidsandi.v.sodiumis,togetherwith the administration of oxygen, the most common medical intervention in the critically ill. It can take the form of fluid resuscitation with single or intermittent boluses of significant amounts of fluid, or be implemented as continuous slow volume infusion or as a combination of both or as i.v. nutrition orasvehicleforintermittentorcontinuousinfusionofdrugs. 1‐4 The speed, amount, timing, and physiological targets for such fluid delivery are determined by clinicians on the basis of physiological reasoning, observational evidence, personal preference, local culture, mentorship, marketing forces, heuristic bias, guidelines, and expert opinion in a manner that makesreproducibilityessentiallyimpossible andcreates enor