permanent localized dilation of artery

50% increase in size of vessel leads to weakening or destruction or arterial wall

athreosclerotic anneuryms occur more often in men than women (increased age is a risk factor)
Aorta is most common site for aneurysm formation however it may form in any vessel

pulsating mass may cause dull pain or pressure however its rare

rupture-causing fatal hemorrhage

dissection-serparation of layers of artery, blood flows between layers

pressure on surrounding structures

thrombus formation, possible embolization, ischemia to distal region

atherosclerosis is most common cause

other causes include congential defects

trauma (blunt and perforating)

infections: syphillis, mycotic aneurysm from fungal infections

hereditary abnormalities of connective tissue

uncontrolled htn enhances development

aging, risk factor after 65, natural vascular changes that occur with age

impaired nutrition over time leads to vascular changes in vessel wall

**aorta-usually at point where artery is not supported by skeletal muscle

aorta under great stress and pressure due to high pressure during systolic ejection of blood and its large diameter

AAA most common however also found in thoracic aorta, illac arteries, femoral and popliteal arteries (rare)

location-artery or venous

etiology-cause (atherosclerotic, hypertesnive, mycotic, syphiliis)

gross appearance-based on shape, anatomic features, and size

layers of vessel walls dilate while one is still in tact

include fusiform, saccular, and dissecting

localized dilation of artery

bilateral outpouching

unilateral outpouching

one side weakens and pouches out

occurs as the hematoma forms a localized enlargement of the involved artery

layers divide

development of pulsating sack around hematoma

maintains comm with lumen of an artery whose wall has been ruptured

a blood clot is retained in the outpouching of the tissue

forms pouch outside the vessel

most common type

rise below the level of the renal arteries but above illac bifurcation

most are asymptomatic until 5-6 cm

most are palpable at 5cm

most commonly fusiform but may be saccular

most accurately diagnosed by ultrasound and CT scan

reeval q 6 months

pulsating mass in periumbilical area slightly to the left of midline w/ or w/o pain

bruits heard

distal variability in BP-pressure in arm>thigh

increased size can cause abdominal and lower back pain

groin and flank pain due to pressure on other structures

enlargement can result in partial intestinal obstruction and upper GI bleed

atheromatus plaque leading to embolization and occulsion of distal vessels causing poor circulation to affected extremity

from aortic arch to level of diaphragm

**most common site for dissecting Aneur

seen in acendeing, descending, and transverse sections of aorta

usually fusiform

commonly develop between origin of l subclavian and diaphragm

clinical manifestations result from compression or obstruction on surrounding areas, dissection, or rupture

most common symptoms when they occur include chest pain, deep and radiating to neck, back, and shoulders

aorta most common site for dissecting aneur

longitudinal splitting of medial layer surrounded by a column of blood

usually afects acsending aorta, aortic arch, and descending aorta

as heart contracts, increases pressure to damaged area and inc dissection

differs from anneurysm in that false lumen if formed sep intima and media layer of vessel

etiology unknown-most have htn

some may have marfans/connective tissue disease

abd or chest xray may show calcifcation that outlines aneur

CT and U/s used to detect and monitor size

MRI/MRA

Spinal CT-gives 3D view

arteriography-allows for visualization of aneur and the vessel

type 1-intima tear, in the ascending aorta with extension in descending

type ii-origin in and is limited to ascending

type iii-arise from within descending and the dissect may proceed proximally distally or both directions

may mimic MI

dyspnea

severe ripping and tearing pain in back and abdomen

pain may be above or below diaphragm

if arch involved-neuro deficits

once detected studies are done to detect size and location

carotid and coronary arteries assessed for atherosclerosis and corrected prior to aneurysm repair surgery

If AAA asymptomatic and smaller than 5cm, surg usually not done

every 6 months and u/s can be done to assess changes

anti-htn meds prescribed to address BP
athero treated w/ cholesterol lowering agents

restrict cholesterol to less than 300mg/day

Pain reduction

Blood transfusions as needed

Monitor for shock caused by leak or rupture

Monitor adequate fluids(IV) and Urine output

Assesstissue perfusion vital organs

Measure serial HCT, HGB

arterial blood to tissue distal to the aneur is reduced during surg

post op nursing considerations aneur-risk for impaired gas exchange

Pt with prosthetic vascular grafts are susceptible to infections

If mesenteric vessels clamped during surgery perfusion to GI tact may be decreased