NEW YORK (CBSNewYork) -- A report issued Monday indicated that Joan Rivers did not consent to a laryngoscopy during which she lost consciousness due to lack of oxygen, and also claimed that physicians did not intervene properly as her condition worsened.
Rivers never regained consciousness after the procedure and died a few days later.
Rivers' daughter, Melissa Rivers, said through her attorneys that the "multiple failings" amounted to more "misconduct and mismanagement" at the clinic.
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Rivers, 81, went into cardiac arrest at Yorkville Endoscopy this August following a minor, elective vocal cord procedure. Reports at the time indicated that her doctor reportedly performed an unscheduled biopsy during the procedure.
Findings from a report released Monday by the Department of Health and Human Services Center for Medicare and Medicaid Services revealed that Rivers did consent to an upper endoscopy that was to involve a possible biopsy, a possible removal of polyps, and a possible dilation of the esophagus.
Rivers also consented to monitored anesthesia and the risks of the procedure were explained to her, the report said.
But Rivers did not consent to another procedure that she underwent before the endoscopy, the report said. A surgeon performed a procedure that involved placing tubes in Rivers' nose with a laryngoscope, and there was no documentation that she was given consent for that procedure as required, the report said.
The comedian's vocal cords seized during the procedures at Yorkville Endoscopy -- a condition called laryngospasm -- and cut off her air supply, according to reports.
As CBS2's Dick Brennan reported, the report also stated that "physicians in charge of the care of the patient failed to identify deteriorating vital signs and provide timely intervention during the procedure."
And as CBS2's Weijia Jiang reported, in a bizarre move, a staffer "proceeded to take pictures of the surgeon and the patient with his cellphone" while Rivers was sedated, saying maybe Rivers "would like to see this in the recovery area," the report said.
The report said further that the medical record lacked the patient's body weight, and the dose of propofol she was given was inconsistent with what was documented in the medical record.
A patient's weight is considered critical to determine how much of the drug to administer.
"Particularly for an elderly person – elderly people metabolize drugs differently, so it's especially important to know the appropriate dose for an elderly person," said CBS2's Dr. Max Gomez.
She died at Mount Sinai Hospital a week later.
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In a statement regarding the Monday report, Melissa Rivers' attorneys said: "Our client, Melissa Rivers, is terribly disappointed to learn of the multiple failings on the part of the medical personnel and the clinic as evidenced by the CMS report. As any of us would be, Ms. Rivers is outraged by the misconduct and mismanagement now shown to have occurred before, during and after the procedure. Moving forward, Ms. Rivers will direct her efforts towards ensuring that what happened to her mother will not occur again with any other patient."
Personal injury attorney Michael Lamonsoff said he believes Rivers' death was preventable.
"Joan Rivers didn't have to die," he said.
Lamonsoff believes Rivers' family will end up suing the clinic. Melissa Rivers hired a law firm last month to begin the process.
"When you have these types of administrative protocols that are flouted or treated laxly, they usually are followed by medical malpractice," he said.
Yorkville Endoscopy issued its own response to the report, saying it was taking action following the incident that preceded Rivers' death.
"From the outset of the August 28th incident described in the CMS Report, Yorkville has been fully cooperative and collaborative with all regulatory and accreditation agencies. In response to the statement of deficiencies, Yorkville immediately submitted and implemented a plan of correction that addressed all issues raised," the statement said. "The regulatory agencies are currently reviewing the corrective plan of action and have been in regular contact with Yorkville. In addition, the physicians involved in the direct care and treatment referenced in the report no longer practice or provide services at Yorkville. Yorkville will continue its commitment to complying with all standards and accreditation requirements."
The New York City Medical Examiner's office said Rivers' cause of death was "anoxic encephalopathy due to hypoxic arrest during laryngoscopy and upper gastrointestinal endoscopy with propofol sedation for evaluation of voice changes and gastroesophageal reflux disease."
That means she suffered brain damage due to a lack of oxygen.
The clinic soon afterward was placed under investigation by the New York State health department.
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