Comparison of intranasal dexmedetomidine versus intranasal ketamine as premedication for level of sedation in children undergoing radiation therapy: A prospective, randomised, double-blind study

Objective: Radiation therapy is indicated in many solid tumours in children. Absolute immobility is required to precisely position children for optimal delivery of radiation energy to the target tissues, improve success rate and reduce the damage to nearby normal tissues. Intranasal (IN) administration of drugs is well tolerated, effective and fast acting. The primary aim of the present study was to evaluate the effectiveness of IN ketamine and dexmedetomidine for providing sedation in children before shifting to the radiotherapy suite. The secondary objective was to assess the requirement of propofol dosage in these patients. Methods: A total of 243 children aged between 1 and 5 years scheduled to undergo external beam radiotherapy were randomised to receive 5 mg kg−1 ketamine (group K, n=80), 2.5 µg kg^-1 dexmedetomidine (group D, n=85) or 0.5 ml of saline (group S, n=78) in each nostril. After 45 min, sedation score was measured according to the modified Ramsay score (MRS) at the time of shifting for radiation. Time to awakening and time to discharge after the procedure were also noted. Results: A significantly higher proportion of children in group D (84.7%) achieved an MRS score ≥3 as compared to group K (36.2%) and group S (3.84%). The total propofol dose (mg kg^-1) required was significantly less in group D (p<0.01). The patients in group D required more time to awakening, but this difference was not clinically significant. Conclusion: The present study demonstrated that IN dexmedetomidine is superior to IN ketamine to provide procedural sedation for radiotherapy in children.