Prevention of rocuronium injection pain in paediatrics: Ketamine versus midazolam? A prospective randomized double blind study

Introduction
Rocuronium bromide is a non-depolarizing muscle relaxant related to mono-quaternary steroid group which is used commonly in general anaesthesia for the facilitation of endotracheal intubation and for maintenance of muscle relaxation. Rocuronium injection pain is a significant drawback with an incidence ranging from 50% to 80% [,]. Separation of children from their parents and shifting them to the OT is an everyday problem to paediatric anaesthetists, in our centre; majority of anaesthetists use IV midazolam to solve this problem, some anaesthetists use IV ketamine hydrochloride instead. This randomized, double-blind study was designed to compare the effect of IV ketamine versus IV midazolam in reducing rocuronium injection-related withdrawal movements in paediatric patients.
Methods
Hundred and twenty paediatric patients aged 2–10 years subjected to urologic procedures under general anaesthesia were randomly classified into two groups: the ketamine group in which IV ketamine 1 mg kg was given and the midazolam group in which IV midazolam 0.05 mg kg was given before shifting the child to the operation room.
Results
Ketamine showed a highly significant reduction in the incidence of rocuronium injection-related withdrawal movements in paediatric patients (-value 0.000) compared to midazolam which was ineffective.
Conclusion
This study demonstrated that ketamine effectively reduced pain after injection of rocuronium in paediatric patients compared to midazolam which was ineffective, and both ketamine and midazolam resolved peacefully the problem of child-parent separation before shifting to the OR.