If its the quick i would cut the rest of the nail down to where the quick is, trying not to cut the quick itself.. Otherwise you'll need to pack the quick to stop bleeding and wrap it for a day or two.. Otherwise the nail will grow mine.. Has happened a lot with me, those dew claws can snag on anything.. Whether its playing, jumping on couch, grabbing a boar or deer, decoy.. etc.. It happens..
If the quick is not damaged it shouldn't have any discomfort, just be careful not to allow to grab stuff with her paws for a week or two until it starts to grow back.. Depending on how far its damaged will depend on how fast.. Last time Kilie split her dew claw was in August, stripped it right down to the fur.. Full quick exposed.. Took a little over a month for the shell/nail to grow back over it and another few weeks to grow further out to cut again..