Hi @vasili
This should be possible, but you will also need to get the page/post id and pass this as the first parameter. The code would look like so:
global $wp_query;
if(is_object($wp_query->queried_object) && $wp_query->queried_object->ID)
{
echo get_post_meta($wp_query->queried_object->ID, 'field_name', true);
}