Evaluation of a Low Dose Ketamine in Post Tonsillectomy Pain Relief: A Randomized Trial Comparing Intravenous and Subcutaneous Ketamine in Pediatrics

Pain control in children is still a therapeutic dilemma. Preschool patientsare affected from undesirable effects of postoperative pain more than adults. Tonsillectomyis associated with a high incidence of postoperative pain, not only complicatingthe recovery, but also delaying patients discharge.Objectives: Despite employing different surgical and anesthetic strategies in post-tonsillectomypain relief, this is still a clinical problem. The study was designed to evaluate theefficacy of a low dose ketamine in post tonsillectomy pain relief.Patients and Methods: Our prospective randomized double blinded study enrolled 75pediatric patients (3-10 years old) who were scheduled for a tonsillectomy procedure.Patients were randomly assigned to one of three groups receiving; intravenous (IV) ketamine0.5mg/kg, subcutaneous (SC) ketamine 0.5 mg/kg and placebo at the end of theoperation. Post-operative pain score was assessed using modified CHEOPS.Results: In our study we did not find any significant difference among the three groupsregarding sex, age, and weight, duration of operation, hemodynamic stability, and nauseaand vomiting. However, in ketamine groups, pain score and analgesic consumptionwere significantly lower (P 0.00). The efficacy of the both ketamine groups was similar.Conclusions: The study demonstrated that the both subcutaneous and intravenous injectionsof ketamine, at the end of the operation, were safe and effective for post-tonsillectomypain control. Ketamine reduced postoperative analgesic medications consumptionwithout increasing the risk of complications.