Aneurysm: Thoracic and Abdominal/ Tissue Perfusion Flashcards
Aneurysm Thoracic & Abdominal
What is an aneurysm?
- A localized sac or dilation formed at a weak point in the artery wall
- Classified by its shape or form
- Types
— Saccular – projects from one side
— Fusiform – entire segment is dilated
Common sites of Aneurysms
most commonly in the abdominal aorta
Characteristics of arterial aneurysms
A – Normal artery
B – False aneurysm – pulsating hematoma
C – True aneurysm; 1,2,or 3 of all layers may be involved
D – Fusiform aneurysm; symmetric, spindle- shaped expansion of entire circumference
E – Saccular aneurysm – a bulbous protrusion of one side of the arterial wall
F – Dissecting aneurysm – usually a hematoma that splits the layers
Thoracic Aortic Aneurysm
- Approximately 70 % caused by atherosclerosis
- Occur most frequently in men 50-70 years
- Most common site for dissecting aneurysms
- Symptoms vary and depend on how rapidly the aneurysm dilates
- How is the pulsating mass affecting surrounding areas
- Patients can be asymptomatic
- Or have pain when supine, dyspnea, cough, hoarseness, stridor, dysphagia
- Can be mistaken for MI
Medical Management of Thoracic Aortic Aneurysm
- Is the Aneurysm symptomatic; expanding in size?
- Caused by a iatrogenic injury?
- Is it dissecting?
- Involving branch vessels?
- General measures
— Control the blood pressure
— Correct risk factors - Surgical intervention
— Repair aneurysm and restore vascular continuity
— Endovascular graft repair
Aortic Disection
- on aortic, disection occurs when blood penetrates the aortic intima and forms an expanding hematoma within the vessel wall
- A dissection result in a separation of the intima and media to create a “ false lumen” or dissecting hematoma
- The intima is compressed by the advancing hematoma
Repair of an ascending aortic aneurysm
Abdominal Aortic Aneurysm
- Caused by atherosclerosis
- Affects men 2 to 6 times more often than women
- Most often occur below the renal arteries
- If untreated; may rupture and cause death
- Pathophysiology
— Weakened middle layer of an artery
— HTN worsens a weak vessel wall
— Rupture
Abdominal Aortic Aneurysm clinical manifestations
- Only about 40% of patients have symptoms
- Feel their heart beating in their abdomen when lying down
- May occlude major vessels if associated with a thrombus
- Severe back pain or abdominal pain may be a sign of impending rupture
- A rupturing aneurysm symptoms may include constant intense back pain, decreasing BP, decreasing H & H.
Abdominal Aortic Aneurysm Medical Management
- Pharmacological – antihypertensive agents
- Endovascular and Surgical interventions
— Endovascular repair for infrarenal AAA
— Can be performed under local or regional anesthetic
Nursing Management of Aortic Aneurysms
- Nursing assessment – Anticipate possible rupture
- Post endovascular repair
— Must lie supine for 6 hours post repair
— Head of bed may be lifted to 45 degrees after 2 hours
— Assess vital signs and Doppler assessment of peripheral pulses every 15 minutes initially
— Assess access site
— Monitor for bleeding
— Notify surgeon of persistent coughing, vomiting or elevated BP
— Assess all systems - Provide Education – blood pressure control, medications
HYPERTENSIVE CRISIS
Patho
Hypertensive Emergency
Blood pressure > 180/120mm Hg and must be lowered immediately to prevent damage to target organs
Hypertensive Urgency
Blood pressure is very elevated but no evidence of immediate or progressive target organ damage
Conditions associated with hypertensive emergency
- Hypertension of pregnancy
- Acute myocardial infarction
- Dissecting aortic aneurysm
- Intracranial hemorrhage
Hypertensive Emergency
Info
- Reduce MAP by 20% to 25% within the first hour
- Reduce to 160/100 mm Hg over 6 hours
— Then gradual reduction over a period of days
— Ischemic strokes and aortic dissections are the exceptions
Hypertensive Crisis
Intravenous vasodilators
- Need very frequent monitoring of BP and cardiovascular status
— Sodium nitroprusside (Nitropress)
— Nicardipine (Cardene)
— Nitroglycerin
Hypertensive Urgency
- Oral agents can be given with the goal of normalizing blood pressure within 24 to 48 hours
- Fast-acting oral agents
— Beta-adrenergic blockers
— ACE inhibitors - Patient requires close monitoring of BP and cardiovascular status
- Assess for potential evidence of target organ damage
Gerontologic Considerations
Hypertensive crisis
- DBP tends to plateau in the late middle age.
- Age-related changes in the great vessels, related to an increase in collagen and decrease in elastin, cause stiffening.
- SBP progressively increases while DBP is unchanged
