The problem you will have in this scenario is that you have to set the value of the new button value in session because you can't get that on content page and when you redirect it you can can simply you can retrieve the value from session and change it in any way you want and take the session variable global so that if you change it the effect is proper.
Session["Patient"]="Patient";
and when you assign it you can do this:
Session["Patient"] = "Book Appointment With Doctor"