The doctors who performed the throat procedure that ultimately led to Joan Rivers‘ untimely death failed to follow routine procedure before sedating her with Propofol, a new report states.

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According to the report, The New York State Department of Health and Human Services found no record of the Yorkville Endoscopy Center’s staff having weighed the late comedienne before administering the dosage of sedative.

This lapse in procedure could have been the reason why Joan stopped breathing during the operation, as she was allegedly given too much of the drug for her weight.

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A staff member reportedly later admitted to the Health and Human Services Department that she made a mistake with the dosage and accidentally gave the Fashion Police star twice the amount of medication needed to sedate her for the procedure.

joan rivers funeral

Melissa Rivers and her 13-year-old son, Cooper, attend Joan’s memorial service on Sept. 7, 2014 in NYC. (Photo Credit: Getty)

The report also stated that Joan’s personal doctor, Gwen Korovin, entered the operating room without authorization during the procedure and performed an unapproved laryngoscopy — an examination of the back of the throat and voice box — while the star was sedated.

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Joan’s daughter, TV personality Melissa Rivers, told Closer she is “outraged by the misconduct and mismanagement” at the Yorkville Endoscopy Center after hearing the latest on her mother’s cause of death.

Joan passed away on Sept. 4 at age 81 from a lack of oxygen to her brain during the Aug. 28 throat procedure.

TMZ was the first to report this news.