Patients will be randomly allocated to three different postoperative strategies : postoperative patient-controlled intravenous analgesia with morphine ( control group , n = 25 ) , a transversus abdominis plane block with ropivacaine 0.375 % at the end of surgery plus postoperative patient-controlled intravenous analgesia with morphine ( TAP group , n = 50 ) , or perioperative intravenous lidocaine plus postoperative patient-controlled intravenous analgesia with morphine ( LIDO group , n = 50 ) .