Joan Rivers' Cause of Death Revealed

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The New York City medical examiner found that Rivers died from lack of oxygen

The New York City medical examiner's office has found that Joan Rivers died from complications due to surgery.

"OCME [Office of the Chief Medical Examiner] 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," spokeswoman Julie Bolcer said in a statement. "The classification of a death as a therapeutic complication means that the death resulted from a predictable complication of medical therapy."

Read more Joan Rivers, Legendary Comedian, Dies at 81

In other words, Rivers died due to lack of oxygen to her brain. A laryngoscopy is a procedure in which a doctor examines the back of the throat and vocal cords; Rivers had been complaining of recent changes to her voice. An upper gastrointestinal endoscopy involves looking at the upper gastrointestinal tract with a light. Both are routine procedures. 

Melissa Rivers said in a statement to The Hollywood Reporter, "We continue to be saddened by our tragic loss and grateful for the enormous outpouring of love and support from around the world. We have no further comment at this time." 

Read more Joan Rivers' Death: Surgery Clinic Receiving Death Threats

The legendary comedian died in New York City on Sept. 4, after what started as a routine procedure at Yorkville Endoscopy, an outpatient surgery center where her gastroenterologist, Dr. Lawrence Cohen, served as medical director. He has since stepped down from that position as the Upper East Side clinic has come under scrutiny following Rivers' death. It has been reported that another doctor, who was not authorized to perform procedures at the clinic, performed a biopsy on Rivers' vocal chords. The clinic has repeatedly denied any biopsy was performed. A spokeswoman for the clinic also said an anesthesiologist always administers anesthesia and that "general anesthesia has never been administered at Yorkville Endoscopy."

Rivers was rushed to Mount Sinai Hospital in New York after reportedly suffering cardiac arrest during the procedure. The New York State Department of Health had launched an investigation into Rivers' death.

On Thursday, a DOH spokesperson told THR in a statement: "The State Department of Health (DOH) has completed its investigation of Yorkville Endoscopy and has forwarded its findings to the Federal Centers for Medicare and Medicaid Services (CMS). Any questions regarding the status of the final determination should be directed to CMS."

A spokeswoman for Yorkville Endoscopy told THR in a statement: "“HIPAA [privacy] laws prevent us from disclosing any information regarding patients.”

Oct. 16, 3:33 p.m. Updated with DOH statement.

Twitter: @lalasoo