Inclusion Criteria:  Age betwween 3 and 15 years Weight < or = 50 kg indicaction of coelioscopic appendicectomy ASA 1,2 or 3 consent of the children and the holder of parental autority  Exclusion Criteria:  Age<3 years or > 15years or weight > 50kg refusal of the children and the holder of parental autority ASA 4 Peritonitis Patients with long term morphinic traitment Epilepsy Hepato-cellular insuffisiancy local anesthesia allergy or nalbuphine allergy coagulation abnomrmality exclusion of health insurance