Dual-Loop Target Controlled Infusion in Laparoscopic Cholecystectomy (DLTCI)

the controller in the current study measures and calculates the error(NI error),which is the difference between the set point(NI=36)and the measured NI.If the NI error is different from 0,the controller determines a new propoflo and/or remifentanil concentration.

the investigator modified the effect-site target concentrations of both drugs without minimum or maximum concentration limits without using the Narcotrend monitor only depend on the experience of anesthesiologist.