Determination of Anesthetics in Aqueous Solution by Infrared ATR Spectrometry

Abstract

One of the priority tasks in anesthesiology is the continuous monitoring of the uptake and elimination of anesthetic during and after anesthesia. The depth of anesthesia depends on the concentration of anesthetics in the brain. Since this is in equilibrium with the concentration in the blood, the determination of the content of anesthetics in the blood is a valuable method for obtaining information about the depth of anesthesia. This can be done by means of infrared spectrometry. The very intensive absorption bands shown by the commonly used volatile anesthetics halothane, enflurane, isoflurane, and gasous nitrous oxide (N₂O) allow the determination of these compounds. Respiratory gas analysis under clinical conditions by infrared spectrometry is well known, using the ordinary transmission technique. In our view, the parameters of blood analysis correlate more significantly with the depth of anesthesia.