Effect of xenon on catecholamine and hemodynamic responses to surgical noxious stimulation in humans

Study ObjectiveTo determine the effect of xenon in combination anesthesia with sevoflurane on the catecholamine and hemodynamic responses to surgical noxious stimulation in humans.DesignRandomized study.SettingA university hospital.PatientsThis study involved 32 female ASA physical status I and II patients, age 20-58 years, scheduled for abdominal hysterectomy.InterventionsPatients were randomly divided into 4 groups: group X50-S1.5, 50% xenon and 1.5% sevoflurane; group X70-S1.5, 70% xenon and 1.5% sevoflurane; group G70-S1.5, 70% nitrous oxide and 1.5% sevoflurane; and group S2.8, 2.8% sevoflurane. No premedication was administered to the patients, and anesthesia was induced by administration of sevoflurane in oxygen and 0.10 to 0.15 mg/kg of vecuronium. After tracheal intubation, the combination of anesthetics was started, and skin incision was performed after equilibration for more than 15 minutes.MeasurementsSystolic blood pressure and heart rate (HR) were recorded, and the plasma concentrations of norepinephrine, epinephrine (E), and dopamine were measured 0, 2.5, 5, 7.5, 10, 12.5, and 15 minutes after skin incision.Main ResultsThe maximal increase in the E concentration and the values of the area under the curve for E were significantly smaller in the X50-S1.5 and X70-S1.5 groups compared with that in the S2.8 group (P < 0.05). At 1 minute after incision, the HR in X50-S1.5 was significantly lower than those in G70-S1.5 and S2.8 groups and the HR in X70-S1.5 was lower than that in S2.8 group (P < 0.01). The systolic blood pressure in S2.8 group at 1 minute was significantly higher than those of other groups (P < 0.01).ConclusionCombination anesthesia using xenon and sevoflurane suppresses the plasma E concentration and hemodynamic response after skin incision more effectively than sevoflurane anesthesia alone.