Declaring and using global variables in a custom admin menu item - php

Question

I'm working on a custom review system. In this project in need to have and ID passed from a callback function which is declared below:
add_action( 'wp_ajax_edit_review', 'edit_review_callback' );
function edit_review_callback() {
check_ajax_referer( 'edit-review-function', 'security' );
$GLOBALS['review_edit_id'] = $_POST['table_id'];
echo $GLOBALS['review_edit_id'];
die();
}
That function is called like this:
$(".edit_review").click(function() {
//Select the right id for selecting right row
var tr = $(this).closest('tr');
var td = tr.find('td:eq(0)').text();
//Create data to send withs security nonce
var data = {
action: 'edit_review',
security: '<?php echo $ajax_nonce_edit; ?>',
table_id: td
};
//Send ajax-request
$.post(ajaxurl, data, function(response) {
alert( 'Response: ' + response );
});
var url = "<?= get_site_url() . '/wp-admin/admin.php?page=sub_menu_item_two_review'?>";
$(location).attr('href',url);
});
I want to set these global variables to use them in my custom menu item.
Which is declared like this:
add_submenu_page(
'review_page_slug',
'review_menu_page',
'Edit review',
'manage_options',
'sub_menu_item_two_review',
'edit_review_render'
);
Some where in here i want to use the variable:
function edit_review_render() {}
Ways I have tried to declare global variables;
global $review_edit_id; $review_edit_id = value;
$GLOBALS['review_edit_id'] = $_POST['table_id']; //As visible in the code below;
Ways I have tried to read variables:
global $review_edit_id; var_dump($review_edit_id); //Same as using the databas with global $wpdb;
var_dump($GLOBALS['review_edit_id']);
echo $GLOBALS['review_edit_id'];
I'm new to wordpress and have been working with it for about 4 weeks by now. I think its fun but I've been stuck on this part since the day before yesterday. Any help woud be much apriciated(and sorry for the big amount of code.).