Dykes has missed his side's last two games with a thigh strain and the midweek defeat to Preston continued the Hoops' poor recent form.
Albert Adomah could come into the reckoning for Warburton after looking lively when he came off the bench in the midweek defeat.
Warburton is already without Luke Amos, who has been ruled out for the rest of the season with a serious knee injury.
Jake Clarke-Salter will be missing from the Birmingham side for the trip to London after sustaining a calf injury in training.
Boss Aitor Karanka had hoped to feature the deadline-day signing from Chelsea but will now be without the defender for at least a fortnight.
Karanka's defensive options are becoming increasingly limited, with Adam Clayton suspended after being sent off in the midweek defeat at Norwich.
Lukas Jutkiewicz is set to miss out again due to coronavirus, while Jon Toral is also unlikely to feature as he continues to battle a groin strain.