The Effects of Parecoxib in Children

Research Design Parecoxib is a intravenous drug and will be administered as a single bolus injection at the induction of anaesthesia for the purpose of this study. Recruitment Group 1 -60 patients age 4 to 15yr. -This allows for the loss of patients either to refusal for further investigations or cannula malfunction. -Tonsillectomy model is being utilised for this study -Patients undergoing tonsillectomy with or without adenoidectomy will be recruited Parental or patient consent will be obtained Patients in group 1 will be randomised to receive parecoxib in either one of these doses 0.25mg/kg, 1mg/kg or 2mg/kg. -Patients will then have 6 blood assays taken in total - 1st blood assay 30 minutes post administration of drug -2nd blood assay in post anaesthesia care unit - 3rd to 6th blood assay taken in day stay unit at 30 minute to 1 hour intervals -Pain scores will also be taken simultaneously with blood assay 2-6 Group 2 -All patients in group 2 will receive 1mg/kg of parecoxib as a single bolus at induction of anaesthesia. -15 patients age 4 to 15yr. -General or Orthopaedic patients All study patients will receive the following drugs. Paracetamol 30mg/kg orally as per day stay protocol prior to induction. Intravenous induction using propofol 2-3mg kg -1 or inhalation induction using sevoflurane. Anaesthesia will be maintained using total intravenous anaesthesia (TIVA), propofol and remifentanil infusion will be used. Lignocaine 1-2mg kg -1 will be used to spray the vocal cords prior to intubation. Ondansetron 0.15mg kg -1 and Dexamethasone 0.15mg kg -1will be used as antiemetics for Group 1 patients. Ondansetron 0.15mg kg -1 will only be given at the discretion of the anaesthetist for the Group 2 patients.