[Hemodynamic changes during slow induction of anesthesia using propofol and the effect of cardiac output on the propofol concentration]

This investigation assessed the hemodynamic changes during the slow induction of anesthesia using propofol, and evaluated the effects of cardiac output (CO) and other factors on the hypnotic dose of propofol, the time for hypnosis and the plasma propofol concentration. We studied 26 scheduled surgical patients and induced anesthesia with continuous infusion of propofol at the rate of 15 mg.kg-1.hr-1. The required dose of propofol and time for hypnosis were determined and the plasma concentration of propofol was measured after the administration of propofol 2 mg.kg-1. Cardiac output was determined by dye densitometry using indocyanine green 4 times during induction and CO did not show any significant changes during induction of anesthesia. Multiple linear regression analysis demonstrated that in addition to the age and total body weight, CO determined at achieving hypnosis was significantly related to the plasma concentration of propofol. Cardiac output might affect the pharmacokinetics of propofol during induction of anesthesia.