The Yorkville Endoscopy, the New York clinic where Joan Rivers stopped breathing a week before her death, denied ever administering general anesthesia or conducting a vocal cords biopsy that has been alleged in media reports as contributing to her demise.

It was the first time the Yorkville Endoscopy clinic issued a statement since August 28, when Joan Rivers was rushed to a nearby hospital from the center with cardiac arrest. She died at age 81 on September 4.

On September 10, New York’s Daily News reported that an unplanned vocal cord biopsy at the clinic had left Joan Rivers unable to breathe.

Joan Rivers’ doctor, who said he was an ear, nose and throat specialist, asked if he could use the clinic’s instruments when another doctor said he had noticed something on Rivers’ vocal cords, and Rivers’ physician was given the go-ahead, a medical source told the newspaper.

“A biopsy like that should only be done in hospital,” the newspaper quoted the unnamed medical source as saying.

“If she had been in a hospital when it happened, she might have been OK.”

In its statement, the Yorkville Endoscopy clinic did not mention Joan Rivers by name.

The cause of Joan Rivers’ death is still unknown pending further tests (photo Getty Images)

“A biopsy of the vocal cords has never been performed at Yorkville Endoscopy,” said the statement.

“General anesthesia has never been administered.”

The cause of Joan Rivers’ death is still unknown pending further tests, according to the Office of Chief Medical Examiner.

The State Health Department is investigating the Yorkville Endoscopy. It is reviewing documents and medical records and interviewing staff and physicians at the clinic in Manhattan’s Yorkville neighborhood, which opened in February 2013.

The clinic said its board-certified anesthesiologists use light to moderate sedation and monitor the patient continuously using state-of-the-art equipment.

“Yorkville Endoscopy has strict policies in place for the criteria of who gets treated in this center versus in a hospital,” it said, adding it also has all the airway equipment needed for emergency intubation.

The Yorkville Endoscopy said it has performed more than 18,000 procedures.

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