Hypothesis : Low dose ketamine has an analgesic effect in children with mucositis treated by patient-controlled analgesia with morphine

Double blind versus placebo multicenter Phase III trial of kétamine in children with chemotherapy induced-mucositis treated by patient-controlled analgesia with morphine

Inclusion Criteria:

• Painful mucositis
• Child from 5 to 18 years.
• Presenting mucitis induced by chemotherapy or a conditioning of graft hematopoïetic.
• A pain not controlled by systematic paracetamol (10mg/kg/4h) or a the propacetamol (20mg/kg/4h).
• Not presenting a neurological or psychological difficulty at the use of the PCA or a EVA.
• First morphine amount going back to less 48h, and lass administration dating of more than 4h at the time of the beginning of the perfusion of Ketamine/placebo (EVA > 30 after stop morphine).
• Assent signed by the parents and each time possible by the child.

Exclusion Criteria:

• The child was already included in the study.
• The age of psychomotor development is lower than 5 years
• Presence of a depression or a major depressive episode according to definition DSM IV.
• Hepatic or renal anomaly major (rank 3 or 4 of the scale of toxicity NCI CTC v2.0)
• Bilirubin>3N
• Gamma WP>3N
• SGOT or SGPT >5N
• Creatinin>3N