comparison of effect of intravenous ketamine, peritonsillar infiltration of tramadol and their combination on pediatric post-tonsillectomy pain: a double-blinded randomized placebo-controlled clinical trial

in this study, the aim was the evaluation of effect of intravenous (iv) administration of ketamine, peritonsillar infiltration of tramadol and their combination for control of post-operative pain in comparison with single use of each drug in children undergoing tonsillectomy. one hundred and twenty children, aged 2-15 years, selected for elective adenotonsillectomy were enrolled in the study. we divided the patients into four groups of 30 each, group i: received iv ketamine 0.5 mg/kg, group ii: received peritonsillar infiltration of tramadol 2 mg/kg, group iii: received iv ketamine 0.5 mg/kg added to peritonsillar tramadol 2 mg/kg and group iv: received iv and peritonsillar infiltration of 0.9% saline. we utilized the children’s hospital of eastern ontario pain scale (cheops) recorded each 15 min after surgery to the    first h and then each 2 , 4, 6, 8, 16, 24 h to assess pain levels postoperatively. the analysis of data showed that group iii had significantly lower cheops scores than another three groups ( p <0.001), while both groups i and ii had the same ranged scores, which were not statistically significant ( p >0.05). during 24 h after surgery, the first time for analgesic requirement was higher in group iii in comparison with other groups ( p <0.001). combined use of iv ketamine 0.5 mg/kg with peritonsillar infiltration of tramadol 2 mg/kg provided better and more prolong analgesic effects compared with using each drug alone in patients undergoing tonsillectomy.