Remifentanil Tapering and Post-adenotonsillectomy Pain in Children

Tonsillectomy is the commonest operation of childhood and results in considerable pain. Remifentanil is a potent, ultra short acting opioid with a long- established safety record in paediatric anaesthesia that is used to provide intraoperative analgesia. There is evidence from adult studies that remifentanil increases postoperative pain, although this may be ablated if propofol (rather than inhalational anaesthesia) is used or if the remifentanil is tapered rather than abruptly discontinued at the end of surgery. The analgesic effect of gradual withdrawal of remifentanil at the end of surgery has not been studied in children and may have significant clinical implications. The primary measure of efficacy will be the dose of fentanyl rescue analgesia in the peri-operative period (1 mcg.kg-1 bolus for \>20% increase in pulse, blood pressure or movement intraoperatively or a FLACC(Face, Legs, Arms, Cry, Consolablity) score of \>5 in recovery).