Having worked in a general ED I completely understand how you are feeling. I am now working in a pedi only ED and love every minute. With kids, don't surprise them. One thing I have learned is to be honest. If you have to start an IV, sit with a set of supplies and show them how it works (retract the needle from the IV) and let them play with it. Google child life videos. We have child life specialists where I work and they are amazing. I have learned so much about how to prep kids from them. For instance, we don't call them IVs but special straws. Also, never tell them not to cry. I have been able to talk many kids into holding still and they still cry. I will straight up say "the most important thing is for you to hold really still. You can cry and that is ok, but hold your arm as still as you can." Always make sure you have someone helping to hold, but life is much easier, for the majority, if you are honest with them.