The 81-year-old comedienne was undergoing a procedure on her vocal chords when complications involving her heart occurred.
A 911 call was made from the endoscopy clinic in New York’s Mount Sinai hospital when the comic’s heart stopped during the routine surgery.
The caller was heard saying: "We have somebody in either cardiac or respiratory arrest."
According to the New York Daily News, a source close to the family said: "This is not looking good. No big medical decisions will be made until [Joan's daughter] Melissa arrives."
Joan made a name for herself with her edgy humour and, more recently, with her often below the belt comments about celebrities on E!’s Fashion Police.
The TV star’s co-hosts- Kelly Osbourne, Guiliana Rancic and George Kotsiopoulos- have yet to comment on Joan’s condition.
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