Details about Joan Rivers' death emerge as lawsuit is filed

Willie Grace | 1/27/2015, 2:29 p.m. | Updated on 1/27/2015, 2:29 p.m.
Attorneys for the estate said they are suing for damages and said the family wants to "make certain that the ...

The lawsuit argues that during this part of the procedure Cohen and Bankulla failed to ensure Rivers' airway was appropriately maintained and that they "failed to properly observe and monitor Joan Rivers' vital signs which were deteriorating" and that her blood pressure "dropped significantly" as did her pulse and oxygen saturation level according to the lawsuit.

After Cohen completed the EGD he took a selife with Rivers while she was under sedation during the procedure, without her consent, according to the lawsuit.

When he took the photo, the lawsuit says, Cohen announced that maybe Rivers would "like to see these in the recovery area."

Dr. Gwen Korovin then said she wanted to "go down again" and take another look, doing another laryngoscopy, the procedure for which the facility did not have written consent, according to the lawsuit.

Korovin performed the laryngoscopy despite a concern voiced by Bankulla that the procedure could compromise Rivers' airway, the suit says, adding that Cohen told Bankulla she was just "being paranoid," and the doctors proceeded with the second laryngoscopy.

According to an October investigation by the medical examiner's office, the cause of death was "anoxic encephalopathy due to hypoxic arrest," a medical description of brain damage caused by lack of oxygen "that happened during the laryngoscopy."

Rivers had a laryngospasm, a spasm of the vocal cords that makes it difficult to breathe, according to the investigation.

Her body was unable to take in enough oxygen and eventually her heart stopped delivering fresh oxygenated blood to her brain, which shut down.

When the doctors did notice that Rivers' vital signs had dropped, as had her oxygen saturation level, they tried to get her breathing better. When 10 minutes of ambu bagging didn't work, the lawsuit says Bankulla asked another doctor to get the tracheotomy kit ready.

In that case, the lawsuit says the doctors should have performed an emergency tracheotomy.

Bankulla looked for Korovin to perform a cricothyrotomy, but the lawsuit says Korovin had left the room.

Korovin is a well known doctor who has successfully treated an impressive list of celebrity clients who have come to her with voice trouble.

The list of famous patients who have sung her praises include actors Hugh Jackman and Nathan Lane and singers Celine Dion, Lady Gaga and Ariana Grande.

Korovin is a licensed medical doctor, but she "did not have privileges to perform surgical procedures" at Yorkville Endoscopy nor was she credentialed to perform procedures at the facility, according to the lawsuit.

After Rivers started to deteriorate further, the lawsuit alleges that Korovin left the room "because she knew she was not permitted to perform medical services or procedures" at that particular clinic and wanted to "avoid getting caught."

The lawsuit also says the doctors were inadequately trained to handle an emergency like the one they encountered.

CNN left voice messages and emails for all the individuals and facilities named in the suit. So far, none has responded to CNN's inquiries.

In relation to this case in the past, the Yorkville Endoscopy clinic has said, "Our anesthesiologists monitor the patient continuously utilizing state-of-the-art monitoring equipment, and remain at the bedside throughout the procedure and into recovery." It added that all its doctors are certified for advance cardiac life support.