Predictive performance of'Diprifusor'TCI system in patients during upper abdominal surgery under propofol/fentanyl anesthesia

Objective:To evaluate the predictive performance of‘Diprifusor’TCI(target-controlled infusion)system for its betterapplication in clinical anesthesia.Methods:The predictive performance of a‘Diprifusor’TCI system was investigated in 27Chinese patients(16 males and 11 females)during upper abdominal surgery under total intravenous anesthesia(TIVA)withpropofol/fentanyl.Measnred arterial propofol concentrations were compared with the values predicted by the TCI infusion system.Performance was determined by the median performance error(MDPE),the median absolute performance error(MDAPE),thedivergence(the percentage change of the absolute PE with time),and the wobble(the median absolute deviation of each PE fromthe MDPE).Results:The median(range)values of 14.9%(-21.6%～42.9%)for MDPE,23.3%(6.9%～62.5%)for MDAPE,-1.9%h(-32.7%～23.0% h)for divergence,and 18.9%(4.2%～59.6%)for wobble were obtained from 227 samples from all patients.For the studied population,the PE did not increase with time but with