There are plenty of ways on how to manage an uncooperative pediatric patient. First is assurance. The kinds should be assured that nothing harmful is going to happen and that you (parents) will always be by their side. Second, Touch and hold. Kids always feel the need to be protected. When we hold them they tend to feel relaxed and protected. Third, Give positive insights and relate it to their super heroes. Fourth, offer rewards if they were able to follow and do what you asked them to. Fifth, show that you are in-charge of the situation in a gentle manner.
