The cardiac arrest leading to Joan Rivers' death happened as the comedian's personal doctor began performing a biopsy on her vocal cords, a source close to the death investigation told CNN.
A staff member at Manhattan's Yorkville Endoscopy clinic told investigators that the doctor, who has not been publicly identified, took a selfie photo in the procedure room while Rivers was under anesthesia, the source said.
Rivers, 81, was at the clinic for a scheduled endoscopy by another doctor, gastroenterologist Dr. Lawrence Cohen. That procedure, intended to help diagnose her hoarse voice and sore throat, involved the insertion of a camera down her throat.
After Cohen, the clinic's medical director, finished his work, a biopsy was done on Rivers without her prior consent, according to the source.
An ear, nose and throat specialist not certified by the clinic as required by law performed a biopsy on her vocal cords. The doctor is described by the source as Rivers' personal ear-nose-throat physician.
"Even though you are a licensed physician, you still should have, if you will, the checks and balances to get your approval to practice in that particular place," said Dr. Arthur Caplan, a medical ethicist at New York University's Langone Medical Center.
Investigators believe that Rivers' vocal cords began to swell during the allegedly unauthorized biopsy, cutting off the flow of oxygen to her lungs, which led to cardiac arrest on the morning of August 29, the source said.
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