Aortoenteric Fistula: What happened to Adele?

Happy New Year, Fans, and Welcome Back from the holidays! 

… Though it's a bittersweet return for us over at Seattle Grace Mercy West. Derek's hand seems to be recovering nicely, Jackson and Intern Stephanie's date ended well, and Bailey and Ben did finally exchange their wedding vows… But we lost one of our most beloved guest characters in Adele Webber. She has been a part of our world for nine seasons, and we'll miss her greatly. Rest in peace, Adele. (And thank you, Loretta Devine, for an amazing, Emmy Award-winning, and heartbreaking performance over the years!)

What was causing Adele to vomit so much blood?

Adele had an undiagnosed, abdominal aortic aneurysm – the main blood vessel in the body, the aorta -- had become enlarged, ballooning outward. Adele's particular aneurysm was so big that it started pushing up against her bowel, specifically her duodenum, and eroded into it. As this process occurred over time, an abnormal connection developed between the aorta and gastrointestinal tract – the condition is called a primary aortoenteric fistula and can be fatal without prompt surgical treatment.

Typically, these patients will first present with a "herald bleed." A blood clot will fill the fistula and cause upper or lower gastrointestinal bleeding as the bowel contracts. This initial episode will have relatively few hemodynamic consequences and can occur hours to days before an accurate diagnosis. Patients may also suffer from back pain and abdominal cramps, which usually sends them to the doctor. And often, when the aneurysm is this big, they will feel a mass in their abdomen.

But Adele is not our typical patient. Due to her Alzheimer's Disease, Adele did not inform anyone of her symptoms and ignored her herald bleed. Her blood clot eventually dislodged from the fistula, which led to her catastrophic vomiting of blood and rapid deterioration.

Bailey and Leah rushed Adele to the Endoscopy Suite to try to find the source of the bleeding.

An endoscopy is the fastest method in diagnosing an aortoenteric fistula. The procedure involves inserting an endoscope (a flexible tube with a light and camera attached to it) into the patient's mouth and down the throat in order to see inside of the digestive tract. Most fistulas may be discovered through this method, but in some occasions, the amount of blood blocks visualization, and a CT Scan may additionally be used. However, if imaging cannot confirm a diagnosis, the patient should proceed to surgery for emergent exploration because…

… Without immediate surgical intervention, aortoenteric fistulas have a 100% mortality rate.

The surgeon's first priority will be to locate the source of the bleed and STOP it – control can usually be achieved initially with a vascular clamp. Then, repairs will be initiated to the damaged aorta and affected piece of intestine, maintaining adequate circulation to the lower part of the patient's body. Frequently, the team will use flaps or grafts in order to prevent another fistula from forming as well as start the patient on multiple antibiotics to reduce the risk of infection.

Unfortunately, even though Bailey and Meredith successfully repaired the fistula, Adele's body had sustained too much trauma, causing her heart to fail after surgery.

Why did this happen to Adele??

As previously stated, Adele suffered from a primary aortoenteric fistula, due to a large abdominal aortic aneurysm. The aneurysm most likely formed from a build-up of atherosclerotic plaque and slowly developed over time. Other causes of a primary aortoenteric fistula stem from some type of inflammation such as syphilis, tuberculosis, mycotic infection or collagen vascular disease.

The more common condition is a secondary aortoenteric fistula – In these instances, a fistula occurs following open aortic surgery due to the formation of a pseudoaneurysm or scarring in the area. Specific risks include: Aortic aneurysm repair with a prosthetic graft, placement of an endovascular stent, tumor invasion, trauma, aortic radiation, or gastrointestinal disease.