A prospective controlled study to determine the blood propofol concentration in anesthesiologists exposed to propofol vapor in the expired gases of patients receiving propofol-based intravenous sedation

Study Objective: To determine the blood propofol concentration of anesthesiologists who were exposed to the expired gases of patients receiving propofol-based intravenous (IV) sedation. Design: Prospective controlled investigation and laboratory analysis. Setting: Operating room of a university hospital and an independent technical laboratory. Subjects: 5 anesthesiologists who independently delivered propofol-based IV sedation to patients presenting for first trimester termination of pregnancy. In addition, a patient receiving propofol-based IV sedation was recruited as a positive control. A laboratory technician who never had previous exposure to propofol was recruited as a negative control. Interventions: Blood samples were obtained from each anesthesiologist before and after an 8-hour work period of anesthesia care of patients as described above. Blood samples were also obtained from the positive control, following propofol-based IV sedation, and the negative control. Measurements: An independent laboratory determined the blood propofol concentrations using a gas-liquid partition chromatograph and verified the results by repeated measurements in order to avoid a laboratory error. The gas-liquid partition chromatograph had an analytic capability that set the detection limit for propofol at 50 ng/mL. Main Results: None of the anesthesiologists had detectable blood propofol concentration in either the pre-exposure or post-exposure sample. The positive control and the negative control had detectable and non-detectable blood propofol concentration, respectively. Conclusions: This experiment did not detect propofol in the blood of anesthesiologists who administered propofol-based IV sedation to patients.