Efficacy and safety of premedication with oral ketamine for day-case adenoidectomy compared with rectal diazepam/diclofenac and EMLA (R)

Background: Because of its pain-attenuating and sedative properties oral ke tamine has been used as premedication in children and adults. We wanted to compare in children scheduled for adenoidectomy safety and efficacy of oral ketamine with a premedication that causes similar preoperative sedation an d relief of pain at the venepuncture site. We also evaluated the effect of i.v. glycopyrrolate added to these combinations. Methods: One hundred children between 10 and 15 kg of body weight scheduled for day-case adenoidectomy were randomly assigned to one of four groups: g roups DG and DS received diclofenac 12.5 mg and diazepam 0.5 mg/kg rectally , EMLA(R) cream at the venepuncture site, and placebo orally; groups KG and KS received ketamine 6.0 mg/kg orally, placebo cream at the puncture site, and placebo rectally; additionally groups DG and KG received glycopyrrolat e 5 mu g/kg, and groups DS and KS received placebo intravenously. We record ed perioperatively scores (open scale 1-9) for strider, sedation, bleeding, nausea, pain, heart rate, the need for analgesics and registered psychotom imesis and well-being at home. Results: The children of the K-groups became more tearful during separation from their parents (P=0.0072). No other differences were found between the ketamine and diazepam/diclofenac groups before and after premedication unt il induction of anaesthesia. Oral ketamine produced unpleasant psychotomime sis in four out of 59 children. During the first 10 min postoperatively, th e score for strider was significantly higher in group KS than in the D-grou ps; strider scores greater than or equal to 6 were seen in one child of the D-groups (DS) and in six children of the K-groups (n.s.), of whom three de veloped laryngospasm (one reintubation). Glycopyrrolate diminished salivati on in all groups, but had no effect on strider scores. Additionally, gIycop yrrolate delayed the onset of eating at home. Conclusion: Premedication with racemic oral ketamine 6 mg/kg does not seem to be suitable for upper airway procedures. Addition of iv. glycopyrrolate before the induction of anaesthesia significantly reduced the scores for sa livation.