Belgian forward Jeremy Doku, who has been in excellent form this season, remains sidelined with a leg injury that kept him out of Sunday's 3-0 Premier League win at Crystal Palace.
"Sunderland in the New Year maybe (for a potential return on January 1). We will see," Guardiola told reporters.
City will also be without John Stones (thigh) and Rodri (hamstring) on Wednesday, while Omar Marmoush and Rayan Ait-Nouri are on international duty at the Africa Cup of Nations.
"When you are one game away from the semi-finals, if you can take it, take it, because you never know when it's coming back," Guardiola said.
James Trafford is set to start in goal instead of Gianluigi Donnarumma, the newly crowned FIFA Men's Goalkeeper of 2025, and Guardiola hinted at other changes amid a packed December schedule of seven matches.
"James is going to play and all the players that didn't play recently are going to play and some from the Academy because three days after that we have West Ham (in a Premier League match on Saturday)," Guardiola added.
"I'm not saying it's not the priority to get to the semi-finals of the Carabao Cup, but normally when we achieve it, it's when we have all the squad, no injuries and we can rotate."
City, four-time League Cup winners under Guardiola, are breathing down Arsenal's necks in the Premier League title race, two points behind the leaders in second place in the table.
