More than a month after Joan Rivers' death on Sept. 4, the New York City Medical Examiner revealed that a lack of oxygen to the comedienne's brain is what killed her.

Calling the complication "predictable," the examiner's office said it found no obvious medical error on the part of Yorkville Endoscopy, the clinic where Joan was undergoing a throat procedure when she went into cardiac arrest.

The New York State Health Department is still continuing their full investigation of the Manhattan practice, but neither Yorkville nor the doctor who performed the surgery have been accused of wrongdoing at this time.

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According to the medical report, the lack of oxygen caused brain damage and Joan's heart stopped after she was sedated with propofol.

After the cause of death was revealed, daughter Melissa Rivers said in a statement to ABC News, "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."

Joan was originally rushed to the hospital on Aug. 28 after suffering complications and was put on life support just a few days later.

"My mother’s greatest joy in life was to make people laugh," Melissa said following Joan's passing. "Although that is difficult to do right now, I know her final wish would be that we return to laughing soon."