Parayko, who is second among Blues defensemen in average ice time per game (22:49), missed the previous seven games because of an upper-body injury.
Jake Allen will start for St. Louis, which has lost two straight (0-1-1) after winning its previous four.
Thatcher Demko will make his second straight start, and fourth in the past 20 games, for Vancouver, which has won eight straight at home and leads the Edmonton Oilers, Calgary Flames, Arizona Coyotes and Vegas Golden Knights by one point for first place in the Pacific Division.