 Recently clinical research has demonstrated the efficacy of computer- controlled endovenous drug delivery system guided by bispectral index score BIS of the electroencephalogram as the control variable. The BIS closed loop CL titration of propofol and remifentanyl target control infusion provides clinically adequate anesthesia with stability of cardiovascular parameters and favorable patients outcomes, including decreasing drug consumption and shortened postoperative recovery times when compared with manual control infusion. 