MacDonald was hit near the boards by the Panthers' Ryan Lomberg in the second period. He was stretchered off the ice.
The Avalanche said MacDonald is currently undergoing further evaluation.
"I heard he's OK, he's walking around, he's doing better,'' said teammate Andre Burakovsky, who had a hat trick in the Avs' 3-2 win. "I'm happy for him.''
Lomberg didn't get a penalty on the play but it did lead to some big hits from both teams the rest of the period.
"A scary moment," Colorado coach Jared Bednar told reporters. "But he's seen our trainers and everything is going good. I think [the hit] might have been clean. ... Physicality is part of the game but I don't love seeing guys go down, especially when they can't get up."