passing vars while reloading admin page

hi,
im trying to paginate the results of a quary in one of my hooked admin pages
the page is under Manage, and it hooks to a plugin’s administration php

now, every time i want to change the page in the quary, i want to reload this same page, changing the page number variable

i want to send it through the url, like this:
…wp-admin/edit.php?page=myplugin/myplugin.php&myvar=value

but after reloading, the variable isnt set

any help? THX!!