Correspondence  |   May 2017
Rapid Fluid Infusion and Depth of Anesthesia
Author Notes
  • Nagoya University Graduate School of Medicine, Nagoya, Japan (Y.U.A.).
  • (Accepted for publication January 11, 2017.)
    (Accepted for publication January 11, 2017.)×
Article Information
Correspondence   |   May 2017
Rapid Fluid Infusion and Depth of Anesthesia
Anesthesiology 5 2017, Vol.126, 985-986. doi:10.1097/ALN.0000000000001577
Anesthesiology 5 2017, Vol.126, 985-986. doi:10.1097/ALN.0000000000001577
We read with great interest the recent article by Itakura et al.1  The authors clearly demonstrated a decrease in plasma propofol concentration during rapid fluid infusion, especially hydroxyethyl starch. Several studies have evaluated cardiovascular effects on plasma propofol concentrations and proposed mechanisms for a decrease in drug concentration.2–4  Itakura et al.1  emphasized the effect of increased metabolic clearance of propofol. It was suggested that rapid fluid infusion would decrease the blood concentration of drugs during target-controlled infusion and recommended that anesthesiologists increase propofol infusion rates up to two times during rapid infusion. However, rapid fluid infusion may affect propofol pharmacodynamics as well as pharmacokinetics.5  Hemodilution secondary to rapid fluid infusion might enhance the hypnotic activity of propofol despite decreasing plasma concentration.4,6  Propofol pharmacodynamics may vary due to many factors, including cardiac output, metabolic rate, and hemodilution (which results in anemia and hypoalbuminemia).5,7  The free propofol percentage is modified by fluid infusion.8  Propofol and hydroxyethyl starch might form a complex and potentially result in a clinically important interaction.9  Thus, the conclusions of Itakura et al.1  may need some revision.
First Page Preview
First page PDF preview
First page PDF preview ×
View Large