159 patients undergoing laparoscopic colon resections will be enrolled and randomized in three different groups.~Patients in the first group will be subjected to the positioning of a peridural catheter with a continuous infusion of ropivacaine 0,2%99 ml+sufentanil 50 mcg at an infusion rate of 4-6 ml/h.~In the second group participants will receive an intraoperative bolus of morphine (0,05mg/kg) and post-operatively a patient controlled analgesia of endovenous morphine (injection dose 1 mg,lock-out 10 minutes,maximum morphine dosage for hour 4 mg).~In the third group the investigators will adopt an intraoperative bouls of morphine (0,05mg/kg) and post-operatively a patient controlled analgesia of sufentanil sublingual tablets( 15 mcg, lock-out 20 minutes)
Objective of the study is to compare three different analgesic techniques in patients undergoing laparoscopic colon resections: peridural catheter, patient controlled analgesia of endovenous morphine and patient controlled analgesia of sufentanil sublingual tablets.