Ketamine does not reduce postoperative morphine consumption after tonsillectomy in children.
BACKGROUND
Tonsillectomy is one of the most frequently performed operations in children and frequently associated with moderate-to-severe pain.


OBJECTIVE
The aim of the present study was to assess the effect of a subhypnotic dose of ketamine on postoperative pain and morphine consumption after tonsillectomy in children.


METHODS
This randomized double-blind study involved 84 children, 2 to 12-year-olds, undergoing elective outpatient tonsillectomy. Children were assigned to 2 groups. Group K received morphine and ketamine, 0.25 mg/kg, at induction and Group M received morphine. Modified Children's Hospital of Eastern Ontario (mCHEOP) scale was used to evaluate postoperative pain. Pain, morphine consumption, and unwanted side effects were recorded for a 24-hour period. One-way analysis of variance and chi2 tests were used for statistical analysis.


RESULTS
Pain scores and adverse events were similar between the 2 groups. Although morphine consumption was less in the ketamine group during the immediate postoperative period, total morphine consumption over the course of the study was not significantly different between the 2 groups. Fewer patients in the ketamine group required supplementary oral analgesia in the postoperative surgical unit.


CONCLUSIONS
The addition of ketamine 0.25 mg/kg at induction of anesthesia did not decrease postoperative morphine consumption in children undergoing tonsillectomy.
Abu-Shahwan
Ibrahim
I
Department of Anesthesiology, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario. iabushahwan@cheo.on.ca
D000700:Analgesics / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004338:Drug Combinations; D004347:Drug Interactions; D005260:Female; D006801:Humans; D007649:Ketamine / Q000008:administration & dosage*; D008297:Male; D009020:Morphine / Q000008:administration & dosage*; D010147:Pain Measurement / Q000187:drug effects*; D010149:Postoperative Pain / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D014068:Tonsillectomy / Q000009:adverse effects*; D016896:Treatment Outcome
D000700:Analgesics; D004338:Drug Combinations; D007649:Ketamine; D009020:Morphine