https://tv.yahoo.com/news/joan-rivers-air-supply-cut-off-unexpected-throat-022500055.html The routine surgical procedure that ultimately took the life of Joan Rivers was the result of an unplanned biopsy on her vocal cords, according to The New York Daily News. The procedure is one that should not be conducted outside of a hospital, according to medical experts who spoke with the New York Daily News. Rivers underwent the procedure at Yorkville Endoscopy in New York, which generally deals with digestive issues. The biopsy caused the “Fashion Police” star's vocal cords to seize, known as laryngospasm. The medical source told the paper that had this procedure been done in a hospital, Rivers may have survived. The source further alleges that Rivers had only signed off on an endoscopy. Representatives for Joan Rivers, as well as her daughter Melissa, did not immediately respond toTheWrap's request for comment. Last week, the New York Medical Examiner's Office told TheWrap that the completed autopsy of Rivers’ body did not yield a firm cause or manner of death, and that further studies would be conducted to determine how she died. Reports were that she stopped breathing while undergoing the throat surgery on Aug. 28. Rivers was immediately rushed to a nearby hospital, but the comedienne did not recover. She was put in a medically-induced coma and put on life support, but she passed away on Sept. 4.