Seabrook took a high hit from Canucks forward Raffi Torres in the second period of Game 3 that many Blackhawks believe should have resulted in a suspension. Seabrook took two more hits before being pulled from Game 3 to be checked for concussion symptoms, but returned to play the third period.
He was held out as his teammates staved off elimination with a 7-2 win in Game 4 and traveled with the team to Vancouver in hopes of playing Thursday night.
Coach Joel Quenneville says there was a chance he could have played, but "he's just not ready."
Vancouver leads 3-1 in the best-of-seven series.