the effect of ketamine on posttonsillectomy pain in children: a clinical trial

introduction: tonsillectomy is one of the most common surgical operations and has such complications as pain, hemorrhage and laryngospasm. pain management is of vital importance in order to reduce the suffering and restlessness in children having undergone tonsillectomy. different studies differ in their findings as to the use of ketamine for postoperative analgesia. the aim of this study was to investigate the effect of peritonsillar injection of ketamine preoperatively on postoperative pain relief.  materials and methods: this was a randomized controlled trial (rct) on sixty 3-12-year-old children. children were randomly assigned to the intervention and control groups. peritonsillar injection consisted of 1 mg/kg ketamine in the intervention group and of normal saline in the control group. an injection of 1 cc was administered on each side five minutes prior to tonsillectomy. pain assessment was performed using the self-report oucher scale and cheops (children's hospital of eastern ontario pain scale) and sedative state assessment was performed using the wilson sedation scale. pain, medication and complications were studied for 24 hours. data analysis was performed using chi-squared test and t-test. results: the ketamine group had a lower pain score compared with the control group (1.40±1.003 compared with 1.53±1.074). the average pain was less in the control group two hours after the surgery. the difference was statistically significant. there was no difference between the two groups in terms of nausea and vomiting incidence.  conclusion: the peritonsillar injection of ketamine five minutes prior to the surgery reduces the post-tonsillectomy pain without causing any complications.