Joan Rivers Cause of Death Revealed

Joan Rivers died of lack of blood oxygen to the brain in a "predictable complication" of throat surgery, according to the New York City Medical Examiner's office.

The comedienne, 81, died Sept. 4. She had been rushed to Mount Sinai Hospital in New York on Aug. 28, after she stopped breathing while undergoing the procedure, and was then placed in a medically induced coma.

The findings were released Thursday in a statement by the Office of the Chief Medical Examiner:

"OCME has completed its investigation. The cause of Ms. Rivers' death is anoxic encephalopathy due to hypoxic arrest during laryngoscopy and upper gastrointestinal endoscopy with propofol sedation for evaluation of voice changes and gastroesophageal reflux disease. The manner of death is therapeutic complication. The classification of a death as a therapeutic complication means that the death resulted from a predictable complication of medical therapy."