Will I be able to add a facebook style notifcation system when using codeigniter

I am no where near up to adding notifcations to my website idea. And I have lot of reading and learning to do. But usually node.js pops up when searching about how to make a notification systems. (I don't really understand what node js is yet or if that needs to intereact with codeigniter or not.)

So I'm not looking for detailed answers explaining how. I just want to make sure I'm not wasting my time making a whole site in codeigniter. Is it possible to add a notification system while using codeigniter? Otherwise I would have to have people constantly refreshing page to see whether someone has commented or not, which would not be acceptable these days.