Characterization of the Temporal Profile of the Anti-nociceptive Effect of Ketamine Bolus Measured With ANI (Keta-ANI)

This prospective observational cohort (n=20) will record ANI continuously around a single IV ketamine bolus in patients scheduled for elective surgery under general anaesthesia to describe the time course of the anti-nociceptive effect.

PKPD modelling will use the Domino pharmacokinetic model and an Emax link model with a ke0 to relate predicted effect-site concentrations to ANI changes; analyses performed with NONMEM. ANI will be sampled every 6 seconds for 5 minutes after the bolus.