But what if you could proactively estimate the right dose before blood pressure starts to drop—especially under general anaesthesia? Each participant first received stepwise norepinephrine infusions while awake, then repeated the protocol under general anaesthesia (using propofol and remifentanil) and simulated surgical stimulation. ConclusionThis research demonstrates a predictable, linear relationship between norepinephrine dose and MAP during general anaesthesia, enabling clinicians to estimate starting doses more accurately. Key pointsThe Eur J Anaesthesiol study found a linear, predictable relationship between norepinephrine dose and mean arterial pressure in healthy volunteers. The dose-response relationship between norepinephrine dose and mean arterial pressure with and without general anaesthesia: A study in healthy volunteers.