McCartin, 26, suffered a head knock in their five-point win over St Kilda after being caught high by debutant Max Heath in the final term at Marvel Stadium on Sunday.
The defender was floored by the impact following the marking contest and had blood on his face as he left the field.
McCartin has an unfortunate history with head injuries, having missed four games last season due to concussion.
His brother Paddy was forced to retire from the AFL two years ago because of concussion issues.
West Coast great Jeremy McGovern was forced into early retirement by the AFL's concussion panel last month, and Essendon's Nik Cox was ruled out for the rest of the season.
Cox, concussed in a tackle at training before Christmas last year, was at least given a pathway to return to the AFL by the panel.
Asked if the Swans had raised concerns about McCartin's playing future, coach Dean Cox said: "No, not at all.
"We've been through concussions a fair bit at this footy club.
"We manage them as well as we possibly can with the player's safety first, and that hasn't changed.
"We'll just keep progressing with Tom, and he's upbeat about getting back to play footy as soon as he possibly can."
Saints youngster Heath escaped sanction for the incident.
McCartin will miss the Swans' SCG clash against former teammate Luke Parker's North Melbourne on Saturday.
The key defender should be eligible to return for their round-20 derby against GWS, but the Swans aren't putting a timeline on his return.
"(It's) day by day. That's all he can do," Cox said.
"And that would be the same as if, you know, Isaac Heeney was in protocols. We'd be doing exactly the same.
"We want them to progress as quickly and as safely as they possibly can."
North Melbourne will be without ruckman Tristan Xerri after failing to overturn his three-match suspension for an incident that resulted in Melbourne midfielder Tom Sparrow being concussed.
Xerri's absence comes at an opportune time for in-form Swans ruck Brodie Grundy, who set up midfielder Errol Gulden for the match-winning goal against the Saints with a hitout.
"A lot of people talk about (Grundy's last) month. For five or six weeks before that month, he wasn't beaten," Cox said.
"Not only wasn't beaten, but actually played to his strengths and impacted the way he always has."
Sydney's finals hopes are slim but alive after their past two win lifted them to 10th (8-9) on the ladder.
They will need to be perfect with six home-and-away rounds remaining, sitting eight points behind the ninth-placed Western Bulldogs, while eighth-placed Fremantle have 44 points.
"The dialogue, certainly around the whole footy club, is we need to play our best footy - hopefully for as long as possible," Cox said.
"You've got to focus on what's right in front of you, and that's North Melbourne."
10°C