A federal investigation revealed that the doctors who operated on Joan Rivers made several egregious mistakes during the surgery that ultimately ended her life.

According to the New York Times, a federal inquiry found that Rivers' doctor failed to notice her blood pressure and pulse "deteriorating" for more than 15 minutes during the procedure at Yorkville Endoscopy.

Released on Monday, the investigation said that Ms. Rivers's blood pressure and pulse decreased precipitously while she was on the operating table on Aug. 28 between 9:12 and 9:26 a.m., yet cardiopulmonary resuscitation began at 9:28 a.m. at the earliest.

The report also contains a list of violations made by other doctors at the clinic.

  • The anesthesiologist originally wrote on Rivers' chart that he administered 300 milligrams of Propofol—more than double the recommended dosage for someone Rivers' size. He later changed the stated dose to 120 milligrams, saying he had made an input error. The staff allegedly never weighed Rivers to determine the appropriate dosage.
  • Yorkville Endoscopy medical director Dr. Lawrence Cohen took photos of Rivers during the procedure, telling investigators he thought she might want to see them after surgery. Investigators note Rivers did not give the clinic any written authorization to take photographs.
  • Dr. Cohen often invited Dr. Gwen Korovin—a personal physician to "many celebrity actors and singers," including Hugh Jackman, Julie Andrews, Lady Gaga, Ariana Grande, Nathan Lane and Celine Dion—into the Yorkville operating room, even though she "lacked the proper credentials."
  • Dr. Korovin allegedly gave Rivers a laryngoscopy—a throat surgery that Rivers had not consented to. The procedure "was aborted because the E.N.T. surgeon stated she could not see very well what she was trying to view."

Rivers' daughter, Melissa, said in a statement released by her attorneys that she is "outraged by the misconduct and mismanagement now shown to have occurred before, during and after the procedure."

Melissa reportedly retained the well-known Manhattan personal injury firm Gair, Gair, Conason, Steigman, Mackauf, Bloom & Rubinowitz for a multimillion-dollar lawsuit against the clinic and the doctors who operated on Rivers. It is expected to be filed in the next month.

[image via AP]