Week 7: Chp 31: Aortic Artery Disease Flashcards
Aortic Artery Disease is also known as?
an aneurysm
Risk Factors
family history, advanced age, male gender, smoking, atherosclerosis, treated and untreated hypertension, high total serum cholesterol, known coronary artery disease, and genetic and/ or metabolic abnormalities
What is the most common site for a dissecting aneurysm?
Thoracic (descending) aortic aneurysm
15000 people in the U.S. die each year of what aneurysm?
abdominal aortic aneurysm (AAA)
Which risk factor is most important?
smoking
-patient can control (modifiable)
What is a major factor in aortic aneurysms?
genetics
What is the hereditary disease most closely linked to an aneurysm?
-Marfans Syndrome
>affects connective tissues, patient is tall and thin with disproportionately long arms, legs, fingers, toes
>this syndrome results in the degeneration of the elastic fibers of the aortic media
What disorders cause AAA (abdominal aortic aneurysm)
- syphillis
- patients born with a bicuspid aortic valve
- Ehlers-Danlos syndrome, a rare genetic disorder
What causes aneurysms?
- chronic inflammation (aortitis)
- blunt trauma (usually from motor vehicle accidents, can cause aneurysms in the descending thoracic or abdominal aorta)
- blunt trauma can cause rupture of aorta
- hypertension
- marfans syndrome
- atherosclerosis
What is an aneurysm?
a permanent localized dilation of an artery that forms when the middle layer (media) of the artery is weakened, producing a stretching effect in the inner layer (intima) and outer layers of the artery
- while the artery widens, tension in the wall increases, further widening occurs, and the aneurysm enlarges
- the diameter of the artery can be enlarged to at least two times the normal circumference
Aneurysms can occur where?
in the three different areas of the aorta
- ascending aortic aneurysm; located in the arch of the aorta
- descending aortic aneurysms or thoracic aneurysms are located above the diaphragm
- abdominal aortic aneurysms (AAA); located below the diaphragm in the abdomen (most common location)
Aneurysms are classified as 2 categories
True or False
True Aneurysms
all three layers of the arterial wall are weakened
-further classified by their shape or form
-most common forms are saccular and fusiform
(saccular only projects from only one side of the vessel; a fusiform aneurysm develops if an entire arterial segment becomes dilated
True Aneurysm: Saccular
projects from only one side of the vessel
True Aneurysm: Fusiform
an entire arterial segment becomes dilated
False aneurysm
not a distortion of the vessel wall but rather a leak from the artery
-pseudoaneurysm
False Aneurysm: Pseudoaneurysm
- leak from the artery
- the leak is confined by the surrounding tissues, and eventually a blood clot forms
- typically caused by iatrogenic trauma that punctures the artery
- known complication of percutaneous arterial procedures such as arteriography
Clinical Manifestations
usually cause no symptoms and are found when a patient is evaluated for another medical condition
- typically occur when a complication such as dissection or rupture occur
- may be a palpable pulsatile mass in the abdomen with the AAA
- sometimes patient presents with chest, back, or flank pain depending on the location of the aneurysm
- the pain is typically not related to any activity and occurs spontaneously
- pain generally reflects a change in the aneurysm that needs immediate attention
- AAA are usually small do not cause any symptom
- majority of thoracic aneurysms are silent, with rupture or dissection constituting first symptoms
- overall only 5% to 10% of patients experience symptoms such as chest, back, or flank pain depending on the location of the aneurysm
Medical Management: Diagnosis
Computed tomography scanning with IV contrast is the gold standard for assessing the size and location of an abdominal or thoracic aneurysm
- abdominal ultrasound or transthoracic echocardiography (TTE) (can be done quickly and efficiently at the bedside and also because of their noninvasive nature and lack of radiation)
- Cardiac MRI (imaging modality that has shown improved sensitivity and specificity versus TTE in detecting aortic dilation) (lack of radiation exposure with MRI compared with CT may make it the imaging modality of choice for aortic dilation
- an ECG is also routinely done to rule out MI because complications of aneurysm usually involve chest pain
Treatment: Medications
focused on reducing the growth rate and preventing the complications of aneurysms
- antihypertensives
- macrolides
- tetracyclines
Medications: Antihypertensives
hypertension is an important risk factor for rupture, so BP is aggressively managed with antihypertensive medications
- angiotensin-converting enzyme inhibitors (ACE inhibitors)
- angiotensin II receptor blockers (ARBs)
- beta blockers
Medications: macrolides and tetracylcines
antibiotics that may inhibit secondary infections implicated in aneurysm development
-have been proposed as a treatment for AAA with varying rationales and degrees of success
Macrolides
antibiotic
-inhibit abdominal aortic aneurysm (AAA) progression by reducing secondary infection within aortic wall
Tetracyclines
antibiotic
-inhibit matrix metalloproteinase (MMP), which is involved in aneurysm formation, decrease the rate of aneurysm expansion
Statins
reduce the progression of atherosclerosis may influence aneurysm growth
Thoracic Aneurysm: Assessment Data
- pain (constant)
- heart failure
- dyspnea
- cough
- hoarseness of voice
- dysphagia
Thoracic Aneurysm: Pain
constant
-caused by stretching of the aortic tissue and impingement on adjacent structures
Thoracic Aneurysm: Heart failure
ascending aneurysms may produce heart failure and its associated symptoms by causing aortic regurgitation
-as the aortic root enlarges, the aortic valve leaflets are pulled away from each other, permitting backward leakage of blood
Thoracic Aneurysm: Dyspnea and Cough
respiratory symptoms caused by distortion and obstruction of trachea by aneurysm
Thoracic Aneurysm: Hoarseness of voice and Dysphagia
caused by distortion of the phrenic nerve or direct impingement on the esophagus by the aneurysm
Abdominal Aneurysm: Assessment data
- pain
- abdominal throbbing
- cyanosis
- blood clots
Abdominal Aneurysm: Pain
pain occurs in the back and abdomen because of impingement on adjacent structures and strecthingof aortic tissue
Abdominal Aneurysm: Abdominal throbbing
noticeable, small pulsating mass near the navel due to increased aortic pressure
Abdominal Aneurysm: Cyanosis and blood clots
blood can pool in the part of the aorta that is bulging, and a blood clot can develop inside the aneurysm
-if the clot breaks loose, symptoms such as pain, numbness, tingling, and cyanosis may result
Surgical Management
size and location of the aneurysm and presence of symptoms are the determining factors
- surgical intervention is shown to be the only treatment effective in preventing AAA rupture and aneurysm related death
- most common surgical procedure for AAA has been a resection and repair (aneurysmectomy); the aneurysm is excised and a graft is applied
- associated with risks
- endovascular aneurysm repair (EVAR) has gained an acceptance as an alternative to open surgical repair with reduce periprocedural risks
- people with an aneurysm less than 5 cm in diameter are advised not to have immediate surgery
Surgical risks
- bleeding
- infection
- MI
- renal failure
- graft occlusion
Surgical Management: endovascular aneurysm repair (EVAR)
an alternative to open surgical repair with reduced periprocedural risks
-endothelial stent graft or EVAR, which involves the transluminal placement and attachment of the suture-less aortic graft prosthesis across an aneurysm; the aneurysm eventually shrinks down onto the stent graft
What is the goal for patients who do not require immediate surgery?
monitor the growth of the aneurysm over time and maintain the BP at a normal level to decrease the risk of rupture
-for those with small or asymptomatic aneurysms regular ultrasounds or CT scans are necessary to monitor the growth of the aneurysm
Elective Surgery
patients with Thoracic Aortic Aneurysms (TAAs) measuring 2.8 in (7cm) in diameter or with abdominal aortic aneurysms measuring 2 in (5 cm) in diameter or those with smaller aneurysms that are producing symptoms are advised to have elective surgery
-a small aneurysm that expands more than 0.5 cm over a 6 month period of time should also be repaired surgically
Geriatric/ Gerontological Considerations for Elective Surgery
-most abdominal aortic aneurysms occur in patients between 60 and 90 years of age
-rupture is likely with coexisting hypertension and with aneurysms more than 6 cm wide
>at this point, the risk of rupture is greater than the risk of death during surgical repair
-elective surgery should be considered carefully if the patent is able to withstand surgery and anesthesia; important that the healthcare team provides the patient and family with all the facts regarding the risk and benefit in order for the patient and family to make the most informed decision
Complications
- aortic dissection
- rupture of the aortic aneurysm
Complications: Aortic dissection
(dissecting aneurysm)
- thought to be caused by a sudden tear in the aortic intima creating a false lumen in the artery opening the way for blood to enter the aortic wall
- degeneration of the aortic media may be the primary cause for this condition, with hypertension being an important contributing factor
- also frequently linked to Marfans syndrome; this is a life threatening emergency because of the loss of circulation to any major artery arising distal to the dissection
- the ascending and descending thoracic aortae are the most common sites but dissections can also occur in the abdominal aorta
Signs and Symptoms of Aortic Dissection
-sudden onset of severe and persistent pain described as “tearing” or “ripping” in the anterior chest or back and extending to the shoulders, epigastric area, or abdomen
-diaphoresis
-nausea
-vomiting
-faintness
-tachycardia
>blood pressure is markedly different from one extremity to another and often decreases because of loss of blood
Complications: Rupture
most life-threatening complication
-rupture causes sudden and extreme loss of blood
Signs and Symptoms of rupture
pain, tachycardia, and differing BPs between extremities
- in extreme cases, pain occurs then loss of consciousness due to hypovolemic shock from massive blood loss
- death rate with a ruptured abdominal aortic aneurysm (RAAA) or dissection is 80%
When do emergency surgical procedures happen?
indicated for patients with a ruptured or dissecting abdominal aortic or thoracic aneurysm
Nursing Diagnosis
- risk for ineffective peripheral tissue perfusion r/t interruption of arterial blood flow
- acute pain r/t vascular enlargement, dissection or rupture
- fear r/t threat of injury or death or the surgical intervention
Nursing Interventions: Assessment
- Vitals Signs
- Neurological Assessment
- Pain
- Peripheral pulses, skin color, and temperature
- peripheral sensation and motor response
- gentle abdominal auscultation and palpation
Nursing Interventions: Vital Signs
hypotension and tachycardia may indicate hypovolemia secondary to a loss of circulating volume
- blood pressure may vary between extremities if dissection is occurring because of the lessening of blood flow distal to the dissection
- hypertension, elevated diastolic pressure, and tachycardia can further weaken the vessel wall, increasing the risk that the aneurysm will enlarge, dissect, or rupture
Nursing Intervention: Neurological Assessment
an aneurysm of the aortic arch can cause neurological symptoms similar to those of a TIA or stroke
-the bulging aorta exerts pressure on the subclavian artery, decreasing blood flow through the common carotid arteries to the brain, causing neurological effects
Nursing Interventions: Assessing Pain
persistent abdominal, chest or back pain indicates that the aneurysm is pushing on adjacent organs and structures and may help pinpoint the location
-pain is also an indicator of a change such as dissection or rupture
Nursing Interventions: Peripheral pulses, skin color, and temperature
weak peripheral pulses, poor color, and cool extremities indicate lack of arterial flow, potentially because of dissection or thrombus formation in the aneurysm
Nursing Interventions: Peripheral sensation and motor response assessment
paresthesia’s or paralysis may indicate pressure against the arteries supplying the spinal cord
Nursing Interventions: Gentle abdominal ausculataion and palpation
pulsatile abdominal masses may indicate an AAA
- a bruit is caused by turbulent flow through the aneurysm
Nursing Interventions: Actions
- administer antihypertensives as ordered (control BP, which is a major risk factor for aneurysm rupture)
- administer statins as ordered (statins lower cholesterol and therefore reduce the risk of atherosclerosis, which may reduce the aneurysm growth rate)
- administer tetracyclines and macrolides as ordered (these types of antibiotics may inhibit AAA progression by reducing secondary infections within the aortic wall)
- administer stool softeners as ordered (prevent strain on the aneurysm during defecation)
- create calm environment to reduce stress (reduction in stress has been shown to reduce BP and therefore lessen stress on the aneurysm)
Nursing Interventions: Teaching
- Signs and symptoms of aortic aneurysm and aortic dissection such as any new chest, abdominal, or flank pain, especially new pain not associated with increased activity
- patients with Marfan’s syndrome should be encouraged to do regular screening and call their provider with any new chest, abdominal, or flank pain
- follow a strict treatment regimen
Why should patients with Marfan’s Syndrome be encouraged to do regular screenings?
patients with marfan’s syndrome are at increased risk for aneurysms due to the degeneration of the elastic fibers of the aortic media that occurs with that disease
-because of the emergent nature of aortic dissection, immediate recognition is essential to allow emergent repair
What is a strict treatment regimen to teach clients?
- compliance with medication
- smoking cessation
- maintaining a healthy weight
- regular exercise
- avoid crossing or elevating legs to decrease pressure on the aorta and iliac arteries
- stress reduction
- following diagnostic testing and screening recommendations (includes regular blood pressure and cholesterol checks)
- obtaining regular ultrasounds to measure the aneurysm growth
Evaluating Care outcomes
achieve this by complying with the prescribed therapy
- blood pressure and heart rate within normal limits
- strong peripheral pulses
- normal skin color and texture
- no complaints of abdominal, back, or chest pain
- no complaints of wheezing and SOB
- no complaints of dysphagia or hoarseness
- a normal neurological assessment
