Use of methadone in the morphine-tolerant burned paediatric patient.

We describe the successful use of methadone in the restoration of sedation and provision of analgesia in two morphine-tolerant, paediatric patients who had suffered significant thermal injuries and were undergoing mechanical ventilation. Both patients had exhibited escalating requirements for sedative drugs while undergoing ventilation yet remained inadequately sedated. The introduction of i.v. methadone in place of i.v. morphine in the sedative regimen rapidly and effectively restored a state of sedation. Hyperalgesia and morphine tolerance appear to be associated; it is proposed that methadone acts primarily, under these circumstances, by re-establishing the analgesic state. Such use of methadone in the morphine-tolerant patient also afforded a concomitant sedative-sparing effect.