Seventy patients were scheduled for radical prostatectomy, were recruited to this prospective single-blind, were randomized and placebo-controlled by trial. They were randomly divided into two groups of 35 patients each by a computer-generated randomization sequence, the TKE (Tramadol + Ketamine + Electroacupuncture), and TK (Tramadol + Ketamine + placebo Electroacupuncture.The randomization performed by the certified acupuncturist.