1. leaving (on, open, unfinished, etc.)
after the -masu stem of a verb; indicates that something is left in an improper state
目は開きっぱなしだ。The eyes are left open.
2. (doing) continuously; constantly; keep ...-ing
after the -masu stem of a verb
全く、こっちが振り回されっぱなしだよ。Honestly, I'm being jerked around constantly.