On August 28, 2014, Rivers experienced serious complications and stopped breathing while undergoing what was scheduled to be a minor throat procedure at an outpatient clinic in Yorkville, Manhattan. Resuscitated an hour later, Rivers was transferred to Mount Sinai Hospital in New York and later put on life support. She died on September 4 at Mount Sinai, never having awakened from a medically induced coma.
The New York City Medical Examiner's Office said that she died from brain damage which was caused by a lack of oxygen.
After nearly two months of investigations, federal officials said on November 10 that the clinic made a number of mistakes both before and during the procedure. Among those were the clinic's failure to respond to Rivers' deteriorating vital signs, including a severe drop in her blood pressure, possibly administering an incorrect anesthetic dosage, performing a surgical procedure without her consent, and other medical-clinic irregularities.