In this multicenter, randomised, placebo-controlled, double-blind trial, hyperalgesia area around the scarce following colorectal laparoscopic surgery (piece removal) will be assessed in 3 groups of patients : group 1: continuous ropivacaine preperitoneal infusion, group 2 : intravenous lidocaine infusion, or group 3 : control group without local anesthetics. All patients will receive parenteral analgesia combining acetaminophen and morphine.

Besides hyperalgesia assessment, immediate postoperative and long-term pain, morphine consumption, and endocrin-metabolic response will be evaluated in this study.

Inclusion Criteria:

• Age 18 to 80
• ASA status 1 - 3
• Colorectal laparoscopic surgery with piece removal
• French speaking
• Written informed consent

Exclusion Criteria:

• laparoscopy without colorectal extraction
• chronic pain
• analgesic consumption during the 24 hours previous to the surgery
• morphine and LA intolerance
• drug addiction
• inflammatory bowel disease
• general inflammatory disease
• sepsis
• anemia < 10 gr/dl
• liver or renal or cardiac insufficiency
• uncontrolled diabetes
• preoperative consumption of opiate/corticosteroid/beta-blockers, and anti-arrhythmic drugs, MAOIs, neuroleptics.
• preoperative consumption of NSAIDs excluding aspirin referred cardiology