What you did was totally correct in more than one sense. If you had just looked at the patient and just declared death without much fuss, the family may have been questioning whether you could have tried more. But by trying to resuscitate for an hour - and more in the hospital - it is more likely they would feel that everyone tried their best to save him. It doesn't ease their grief, but in time they will realise the hopelessness of the situation and take solace that you all did all you could.