The current API doesn't have a sorting option for listing playlist items, but if you are inserting the items programmatically, you can specify the position
value when inserting to make new videos appear at the top of the list.
If it's someone else that is adding the videos, than you'll have to get all pages. Since the playlists are limited to 200 items, this requires 4 requests at most. Not ideal, but it's the only option now.