On-line determination of serum propofol concentrations by expired air analysis

Propofol (2,6-diisopropylphenol)—an intravenous anaesthetic—can be identified and quantified in expired air directly. For the first time, a β -radiation ion mobility spectrometer operated in the positive mode and coupled to a multi-capillary column for rapid (seconds–minutes) pre-separation (MCC/IMS) was used for the quantification of Propofol in expired air. The comparison of the concentrations in exhaled air (300 ppt V –5 ppb V ) and in serum (0.3–5 μg/mL) showed satisfying agreement affirmed by a correlation coefficient of 0.73. Therefore, MCC/IMS is an adequate method to determine Propofol concentrations in exhaled air and may be applied for the prediction of venous concentrations or for automatic anaesthesia control.