NEW YORK (KABC) -- The New York clinic where comedy legend Joan Rivers went into cardiac arrest may lose its certification on Jan. 7, 2015, unless the clinic can prove it has corrected a number of deficiencies, according to state officials.
A report from the U.S. Department of Health and Human Services found employees at Yorkville Endoscopy photographed Rivers with a cell phone while she was sedated, improperly documented how much propofol was used, and "failed to identify deteriorating vital signs and provide timely intervention."
Rivers was undergoing an upper gastrointestinal endoscopy to treat voice changes and acid reflux when she went into cardiac arrest on Aug. 28. After the procedure, Rivers was taken to Mount Sinai Hospital and put into a medically-induced coma. She died on Sept. 4 at the age of 81.
Medical examiner spokeswoman Julie Bolcer said that the cause was brain damage due to lack of oxygen. It is classified as a therapeutic complication, which means the death resulted from a predictable complication of surgery.
Lapses at the Upper East Side clinic were later found in four categories necessary for accreditation, including governing body and management, surgical services, medical staff and patient rights.
Yorkville Endoscopy says it has been cooperating with regulatory agencies.
"The regulatory agencies are currently reviewing the corrective plan of action and have been in regular contact with Yorkville," the clinic's statement added. "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."
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Rivers' daughter, Melissa Rivers, has retained attorneys Jeffrey B. Bloom and Ben Rubinowitz to investigate her mother's death.
"Our client, Melissa Rivers, is terribly disappointed to learn of the multiple failings on the part of medical personnel and the clinic as evidenced by the CMS report," her attorneys said Tuesday in a prepared statement. "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."
ABC News contributed to this report.