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 ...

(CNN) -- The estate of the late comedian Joan Rivers filed a lawsuit Monday in New York County Supreme Court detailing alleged missteps by the outpatient endoscopy facility and the physicians caring for Rivers during an August 28 procedure that the New York medical examiner said ultimately led to her death.

Rivers died at Mount Sinai Hospital on September 4, 2014.

Attorneys for the estate said they are suing for damages and said the family wants to "make certain that the many medical deficiencies that led to Joan Rivers' death are never repeated by any outpatient surgery center."

The lawsuit alleges that the doctors who performed the procedure at Manhattan's Yorkville Endoscopy clinic were "reckless, grossly negligent and wanton."

The lawsuit says they performed procedures to which Rivers did not consent.

It also alleges that one of the doctors did not have credentials or privileges to treat patients at the facility.

The comedian went to the medical center for a procedure to evaluate her "voice changes" and to determine what was causing her stomach reflux, according to the New York medical examiner.

The lawsuit says Rivers signed an authorization and gave her consent to let the doctors perform an upper endoscopy, or EGD, with possible biopsy/possible polypectomy and possible dilation of the esophagus. It was unclear if Rivers had given verbal consent to any other procedure before being sedated. The lawsuit maintains she did not.

During an upper endoscopy a camera is inserted to examine the upper part of the digestive system. A doctor controls the tiny camera on the end of a flexible tube. It is used to diagnose stomach, esophagus and small-intestine problems.

A biopsy would be done if a doctor found an area that looked like there was some kind of cancer. Voice changes can be a sign of throat cancer.

A polypectomy is done to remove nasal polyps, which are benign growths originating in the mucous membrane that can block the nasal passages.

During esophageal dilation doctors dilate or stretch the narrowed area of the esophagus, which they may do as part of a sedated endoscopy procedure. It's most commonly done because the esophagus has narrowed from acid reflux. Often patients with this problem have trouble swallowing and sometimes have pain. Less commonly, narrowing happens because of cancer of the esophagus.

Rivers first underwent a laryngoscopy. This is a procedure she did not consent to in writing. It is used by doctors to get a look at the vocal folds and glottis. It was during this first procedure that her doctors had "difficulty maintaining" her oxygen saturation at an "appropriate and safe level to ensure that her airway was not compromised" the lawsuit says.

Then Dr. Lawrence Cohen and Dr. Renuka Bankulla performed the upper endoscopy, the procedure for which they did have written consent. When Bankulla noticed the oxygen saturation level again dropped, the lawsuit says she requested that the EGD be stopped and the endoscope removed to increase Rivers' oxygen level.

Once her level was raised, Cohen reinserted the laryngoscope and continued the EGD.