Ketamine and midazolam decrease cerebral blood flow and consequently their own rate of transport to the brain: an application of mass balance pharmacokinetics with a changing regional blood flow
Mass balance pharmacokinetics, with simultaneous blood sampling from an artery and the internal jugular vein, was used to characterize the cerebral uptake of ketamine, norketamine, and midazolam in normoventilated pigs. Intravenous injections of ketamine or midazolam decreased the cerebral blood flow (CBF) by one third, as measured by intermittent 133Xe washout. By means of pharmacodynamic models,