Opioid-sparing effect of ketamine during tonsillectomy in children

In the adult population, Ketamine is currently used as an antihyperalgesic and opioid-sparing agent during the perioperative period. However, for doses of ketamine up to 0.5mg/kg, these effects have not been found in pediatric population. The aim of the present study was to evaluate the efficacy of a preoperative bolus of 1mg/kg of ketamine on postoperative pain intensity and morphine consumption in children undergoing tonsillectomy. We have undertaken a retrospective comparison of 60 consecutive children operated for tonsillectomy in our institution before (first 30 patients) and after (last 30 patients) the introduction of a preoperative bolus of 1mg/kg of ketamine. Data collected were: age, ASA score, dose of intraoperative sufentanil, OPS score during PACU stay and the first postoperative day, morphine consumption during PACU stay and the first postoperative day, psychodysleptic manifestations, pain at first solid oral intake and postoperative respiratory complications or haemorrhage. No difference was found between the two groups in terms of demographic characteristics. Perioperative doses of sufentanil, postoperative opioid consumption or pain score in PACU or during 24hours were similar between the two groups. The two groups did not differ in terms of pain at first oral intake, or other adverse effects. These results suggest that 1mg/kg of ketamine administered right after anaesthesia induction in children undergoing tonsillectomy did not result in an opioid sparing effect.