To limit the scope of what you are renaming you could try the Rename with Preview functionality. For example, starting with the code below and a requirement to rename "emp" to "employee"
what I did was rename emp to employee in the foreach line:
then click the little red indicator (smart tag) that appears to the bottom right of the renamed variable. That brings up a context menu where "Rename with Preview" can be selected.
That menu option brings up a dialog where instances can be checked or unchecked as desired to limit the scope of the renaming operation.
This may vary depending on the versions of Visual Studio and ReSharper that you are using but it definitely works for Visual Studio 2010 and ReSharper 7 as that's what I tested it on.