Leaking Abdominal Aneurysm, Mesenteric Embolism or Thrombosis

Question 1

Where do leaking abdominal aneurysms usually occur? What are the two types?

Answer 1

Below the renal arteries (abover the bifurcation of the common iliac)

Can be saccular (outpocketing) or fusiform (diffuse swelling)

Question 2

What is often the cause of a leaking abdominal aneurysm? When and where do they rupture ?

Answer 2

Usually due to a thrombus on top of a plaque (atheromatous vessel wall with overlying mural thrombi)

They may rupture into the peritoneal or retroperitoneal tissue which is almost always fatal - prone to rupture when they reach 6-7cm

Question 3

How are aortic aneurysms surgically fixed?

Answer 3

Most aneurysms are conveniently located below the renal arteries so that surgical resection can be performed with placement of a dacron graft

Question 4

Describe the clinical presentation of a leaking abdominal aneurysm.

Answer 4

• Severe central abdominal pain, commonly radiating to the back and may be to the groin along the course of the genito-femoral nerve.
• The patient may collapse from the accompanying hypotensive shock or suddenly die.
• Often the patient is a smoker with a history of angina, MI, intermittent claudication, TIA or stroke.

Question 5

What are the degrees of severity of ischaemic bowel disease?

Answer 5

Question 6

List some causes of ischaemic bowel disease.

Answer 6

Question 7

Describe the pathology of transmural infarction in ischaemic BD.

Answer 7

Arterial or venous side is occluded –> infarction which appears haemorrhagic because of blow reflow to the damaged area

Within 1-4 days intestinal bacteria produce gangrene and perforate the bowel

Question 8

Describe the clinical presentation of mesenteric embolism or thrombosis.

Answer 8

• Severe and continuous pain which quickly develops all the all the hallmarks of peritonitis
• Generalised pain accompanied by vomiting
• History of angina, MI, intermittent claudication, TIA or stroke.

Question 9

What is Virchows Triad?

Answer 9

Factors that predispose to thrombosis:

1. Changes to the constitution of the blood - hypercoagulability
2. Changes to the blood flow - haemodynamic changes
3. Changes to the wall - endothelial dysfunction/injury