Goalkeeper Allan McGregor and midfielder David Meyler both picked up knee injuries in Thursday's spirited 3-2 defeat at home to Manchester United, both withdrawn at half-time in the KC Stadium clash.
Bruce's son, Alex, is also a doubt for the encounter with Rene Meulensteen's men after sustaining a calf injury during the fixture against United.
The three are now set to undergo tests before the Fulham fixture.
"Both Allan and David had knee injuries," Bruce said. "They'll have x-rays and scans on Friday.
"David's is a concern because it's the knee he injured when he was out for so long (at Sunderland) while Allan's came after the challenge by Ashley Young in the first few minutes.
"Alex has got a calf problem and there's one or two others that have picked up problems. We'll see how they are and I can't really say at the moment who will be fit for Saturday."
Bruce was disappointed his charges were unable to hold onto a 2-0 lead against David Moyes' men, and said results are more important than earning credit in a losing performance.
He added: "The big question is whether we can find another performance like that. It's a huge, huge game for us and a chance to pick up some points against a team below us in the table.
"It's alright getting the plaudits for performances against the Manchester Uniteds, but we've got to make sure we produce performances against teams in and around us like the one we'll be facing on Saturday.
"The big teams like Manchester United will come here and expect to beat us. I don't think Fulham will come here and play with four up front like United did, so we have to find a way (of breaking them down)."
