Details behind Joan Rivers' procedure

NEW YORK -- So what are the risks and complications in the kind of procedure that Joan Rivers underwent?

Just after 9:30 Thursday morning, law enforcement officials arrived at Yorkville Endoscopy.

There had been an emergency call that Joan Rivers had reportedly stopped breathing during a minor endoscopic procedure.

Endoscopy refers to a tiny camera that doctors use to look inside the body.

E News is reporting the 81-year-old comedian had a procedure to look at her vocal cords.

This clinic however focuses on digestive disorders.

"Most vocal cord procedures are done in a hospital under general anesthesia or ambulatory surgery center," said Dr. Yosef Krespi, of Lenox Hill Hospital.

As an ear, nose, and throat specialist at Lenox Hill Hospital, Dr. Yosef Krespi was not involved in the care of Joan Rivers. But, he says any endoscopic procedure involving the throat comes with a risk of an airway spasm.

"That by itself can cause depletion of oxygen, inability to inhale air, and therefore cardiorespiratory problems," Dr. Krespi said.

As questions remain regarding what went wrong, there's a reminder that all procedures come with risks.

"Obviously the older and younger the patient, we are more concerned, we are more concerned with the risks of anesthesia," Dr. Krespi said.