Seyed Alireza Bameshki - Cardiac Anesthesia Research Center, Imam-Reza Hospital, Faculty of Medicine, Mashhad University of Medical Science, Mashhad, Iran.
Mohammad Reza Salari - Cardiac Anesthesia Research Center, Imam-Reza Hospital, Faculty of Medicine, Mashhad University of Medical Science, Mashhad, Iran.
Mahdi Bakhshaee - Sinus and Surgical Endoscopic Research Center, Ghaem Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Majid Razavi - Cardiac Anesthesia Research Center, Imam-Reza Hospital, Faculty of Medicine, Mashhad University of Medical Science, Mashhad, Iran.

Introduction: Tonsillectomy is the one of the most common types of surgery in children, and is often accompanied by post-operative pain and discomfort. Methods of pain control such as use of non-steroidal anti-inflammatory drugs (NSAIDs), narcotics, and local anesthetics have been used, but each have their own particular side effects. In this study we investigated the effect of ketamine on post-operative sedation and pain relief.   Materials and Methods: A total of 50 children aged between 5 and 12 years who were candidates for tonsillectomy were divided into two groups. The study group received ketamine-midazolam (ketamine 1 mg/kg, midazolam 0.1 mg/kg) and the control group received midazolam (0.1 mg/kg) in the pre-operative period. The same methods of anesthesia induction and maintenance were used in all patients. Pain score was assessed using the Wong-Baker Faces Pain Rating scale and sedation was evaluated using the Riker Sedation-Agitation scale at the time of extubation as well as 5, 10, 15, and 30 minutes and 1, 2, and 6 hours after surgery.   Results: The two groups were similar in terms of age, weight, gender and duration of surgery. Pain after 15 and 30 minutes and agitation after 10 and 15 minutes following extubation were lower in the study group (ketamine-midazolam). Mean consumption and time of first request for analgesia after surgery as well as incidence of post-operative vomiting were similar in the two groups.   Conclusion:  Adding ketamine to midazolam in pre-operative of tonsillectomy reduces agitation and post-operative pain in the first 30 minutes after surgery.

Children, Ketamine, Post-operative pain, Sedation, Tonsillectomy