[Pharmacokinetic simulation of high-dose administration of dexmedetomidine for decubitus treatment]

We used only dexmedetomidine to sedate a patient with Alzheimer disease, Parkinson's syndrome and emaciation for decubitus treatment in the prone position. The infusion rate of dexmedetomidine without a loading dose was increased until sufficient sedation was attained. The maximum plasma concentration and the plasma concentration in a stable state, which were calculated by pharmacokinetic simulation analysis, were 2.3 ng x ml(-1) and 1.5 ng x ml(-1), respectively. Respiration disorder did not occur and hemodynamic stability was preserved despite administration up to 11.5 mcg x kg(-1) x h(-1). An increase in the dose per weight was needed to increase the absolute dose because of emaciation. It was found by pharmacokinetic simulation analysis that the plasma concentration of dexmedetomidine required for decubitus treatment might be higher than the plasma concentration considered to be necessary for sedation in intensive care units. The simulation was conducted to administer dexmedetomidine, to estimate hemodynamic reaction, and to estimate the necessary plasma concentration. We conclude that dexmedetomidine is useful as an anesthetic agent for decubitus treatment in the prone position, although further investigations with regard to its safety are required.