A modeled concentration and a dose delivered over time can both describe a sedative requirement, but they have different units and answer different questions.
A randomized gastroscopy trial assigned 150 adults to five remimazolam dose groups, including a control group. The estimated propofol effect-site concentration associated with the study’s response in half of patients fell from 3.05 micrograms per milliliter at the lowest active remimazolam dose to 1.47 at the highest. Average propofol use per kilogram per minute also fell, from 0.587 in controls to 0.298 at the highest adjunct dose.
The effect-site value came from a model and was linked to a specific response. It is not a measured plasma concentration. The dose rate describes drug delivery and cannot be substituted for the modeled concentration. The trial did not find a significant difference in recovery-unit duration, illustrating why drug-sparing and workflow outcomes need their own measurements.