Yes, you can. It should not remove the Scene; do you mean that you're changing the Image Source you're using for a backdrop behind the chromakey(ed camera?)
You can add a second Image Source behind the existing one, configure it, then set the one you wanted to switch away from as 'not visible' (eye icon in the Sources list). You can also go into Studio Mode, and make changes in the Preview window. I do not believe they should update to the Program (live) window until you hit the Transition button.
Need more information about the problem to be able to assist further.