Randomization and masking
We aimed to randomly assign 50% of patients to either natriuresis-guided therapy or SOC. Randomization was done using the EHR (EPIC). To get random treatment allocation, a random number generator within the EHR was used that returned either 0 (zero) or 1. This variable was randomly generated within each individual patient file and hard-coded and could not be altered after the number had been generated. Via this way every patient had a 50% chance of being allocated to one of both randomized treatment groups—in analogy to ‘flipping a coin’. On the basis of this number, a study specific orderset was filled with treatment-arm-specific orders, which was ordered upon start of intravenous loop diuretic therapy. This trial was an open-label study. However, to prevent contamination and cross-over between treatment arms, physicians and investigators were blinded to all urinary sodium measurements (timed collections as well as spot urinary sodium) in the SOC arm. More details on the use of the EHR and blinding has been reported previously