She is known for her number of plastic surgeries, but while undergoing a procedure today Joan Rivers stopped breathing. And reports are that she is currently in critical condition.

81-year-old Rivers was having a surgery done on her vocal chords at a doctor's office in New York this morning when reports say she stopped breathing and had to be rushed to Mount Sinai Hospital.

According to the NYPD Rivers is in critical condition at the hospital and TMZ reports that at one point her heart had stopped beating.

At this time it is unclear if doctors were able to restart her heart, but her daughter Melissa has been contacted and is en route to New York City.

Update: E! News' Ken Baker tweeted just before 1pm that Joan has been upgraded to stable condition

Update: As of this morning Melissa Rivers say her mother is resting comfortably at the hospital after suffering cardiac respiratory failure during her procedure Thursday. She has cancelled several upcoming performances to rest and recuperate.