To add to my earlier post.
Know your limitations. The reality is that you will restrain people, you will have to put limits on what people do - that is the nature of PICU, it is an incredibly restrictive environment for the most unwell (although of course I would argue that I was not unwell enough to be in PICU!) I think just caring and being realistic is the best you can hope for from an HCA. I am still in hospital at the moment (transferred from PICU a month ago) and the nurses, HCAs who acknowledge that I am feeling crap and that it won't change overnight are the ones I find the most helpful. They are optomistic for my recovery but they also validate that I am feeling very low.