Fig. 6. The effect of sevoflurane (second panel ) on electroencephalogram-derived parameters (95% spectral edge frequency [SEF], canonical univariate parameter [CUP], and Bispectral Index [BIS]) during a 40-min study period and during abdominal gynecologic surgery, lasting 150 min, in a 45-yr-old patient. During the study period and surgery, the remifentanil target concentration was kept constant at 4 ng/ml. At t = 46 min (I), the patient underwent intubation (after muscle relaxant was administered); at t = 50 min, surgery started; at t = 210 min, surgery ended; and at t = 214 min, the patient underwent extubation (E). The line through the electroencephalographic data is the model prediction derived from the Bayesian parameter estimates obtained during the study period. Prediction of the changes in electroencephalographic effect during surgery were good for CUP and BIS (R20.749 and 0.688 for CUP and BIS, respectively) but poor for SEF (R20.371). On top, the mean arterial pressure (MAP) is shown.