Answer:
Explanation:
There are several approaches and surgical techniques in the reparation of an abdominal aortic aneurysmectomy according to the recent studies. In certain cases, it is recommended to use standard dacron graft with a flexible collar (the collar graft). The other one applies standard dacron graft.
Abdominal aortic aneurysm (AAA) is linked to 1.3% mortality in the male population older than 65-85 years. AAA is defined as the degradation of the elastic media of the previously atheromatous aortic wall. AAA occurs between the aortic hiatus in the diaphragm (T12 vertebra level) and the bifurcation into the common iliac arteries (L4 level). The diameter of the normal aorta varies in the population. In men, it is between 16 to 22 mm.
The most common risk factors for the AAA developing are smoking, male sex, older age, hypertension, hyperlipidemia and previous vascular disease.
The most common symptoms of AAA are a pain in the abdomen, chest or lower back. The presence of peripheral vascular disease if thrombus formation is present within the aneurysm or mural emboli decrease blood flow to the periphery. In certain individuals, there is a ureteric obstruction due to the compression. The diagnosis is performed by bimanual palpation in the region above the umbilicus. Other diagnostic imaging is necessary most commonly via ultrasound and CT scan.
Open repair is performed under general anaesthesia. The abdominal cavity is entered via a midline incision, the AAA is detected. Proximal control is provided with the clamp to the aorta (below the renal arteries). The distal control is provided via clamping the common iliac arteries. The aneurysm is opened and any thrombus removed. A graft is anastomosed to either end of the affected region of the aorta. Thus, clamps are removed and blood flow is maintained.
EVAR repair is performed by the stent-graft placement within the aneurysm which requires CT angiography preoperatively. The graft has 2 components, of which both are inserted on catheters under fluoroscopic guidance. EVAR is performed under local anaesthesia with sedation, epidural or spinal block.
The main body of the graft is inserted via the common femoral artery, while the contralateral is then inserted via the other femoral artery. In this way, there is an entirely new lumen for the distal aorta and proximal common iliac arteries.
In the case of an endovascular repair of abdominal aortic aneurysms, total percutaneous access or endovascular aortic aneurysm (EVAR) has been documented. In this approach, the most common material used may be constructed from self-expanding nickel-titanium (nitinol) with polyester graft material. The complications are defined as suture break (separation of adjacent metallic rings) and metal-ring fracture.
The most common postoperative complications are pseudoaneurysm, haematoma, graft-enteric fistula, suture line disruption. In case of open abdominal repair, there is always a possibility for a hernia complication and connective tissue disorder.
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