Paetsch is out indefinitely with a concussion, leaving the Sabres' depleted defense down a third player in the midst of their final playoff push.
Paetsch will miss "a pretty good period of time," Sabres coach Lindy Ruff said Thursday.
The defenseman had just passed the puck from deep in the Buffalo own zone early in the second period of Pittsburgh's 7-3 victory Wednesday when Laraque skated by and hit him with a raised elbow. Paetsch lay face-first on the ice for several minutes before getting to his knees.
He was assisted to the Sabres dressing room.
Laraque drew a five-minute penalty and was ejected from the game. The suspension will cost Laraque $20,855.61 in salary that will go to the Players' Emergency Assistance Fund.
Laraque will sit out against Philadelphia on Sunday, next Tuesday at the New York Rangers, and March 20 when the Penguins face Tampa Bay at home.
He will be eligible to return March 22 against New Jersey.