Luongo, a two-time NHL all-star, was injured while making what appeared to be a routine save on a shot by Philippe Boucher about five minutes into the game.
He slowly collapsed to the ice and was assisted off while favouring his left leg.
No official word on his condition was immediately available.
Curtis Sanford replaced Luongo in goal.
Luongo, twice a finalist for the Vezina Trophy, entered the game ranked seventh in the NHL in save percentage (.928) and ninth in goals-against average (2.18) this season for a Vancouver team that has not lost in regulation in eight games.