Week 7: Chp 31: Peripheral Arterial Disease (PAD)

Question 1

Main Contributor to PAD; main risk factor

Answer 1

-atherscelrosis

Question 2

Modifiable Risk Factors

Answer 2

• smoking
• hypertension
• diabetes
• dyslipidemia
• sedentary lifestyle
• obesity
• ineffective stress management

Question 3

Non-modifiable risk factors

Answer 3

• age
• gender
• ethnicity
• family history
• a strong family history of coronary artery disease or PAD is an important predictor of its occurrence and subsequent prognosis

Question 4

Peripheral Arterial Disease

Answer 4

progressive and chronic condition, where the obstruction of blood flow through the large peripheral arteries causes a partial or total arterial occlusion

• deprives the lower extremities of oxygen and nutrients; the result of this inadequate tissue perfusion can be ischemia and necrosis, or cell death
• affects the limbs and is a manifestation of systemic atherosclerosis

Question 5

PAD can be caused by?

Answer 5

caused by a combination of atherosclerosis, inflammation, stenosis, embolus, and thrombus

Question 6

Clinical Manifestations

Answer 6

may be asymptomatic, identified only by a reduced BP in the ankle, or it may manifest symptoms of intermittent claudication, or atypical lower extremity pain

• person with PAD typically experiences profound limitation in exercise capacity and quality of life
• will vary with the tissues involved and the severity of altered blood flow
• early stage–> classic leg pain (intermittent claudication), fatigue and pain in a specific muscle group during exertion

Question 7

Intermittent Caludication

Answer 7

muscle pain–ache, cramp, numbness, or sense of fatigue, classically in the calf muscle, that occurs during exercise and is relieved by a short period of rest

Question 8

Atypical Leg Pain

Answer 8

limited or painful joints, cold and/ or ulcerated extremities, or painful stretching
-exercised induced and rest relief

Question 9

The vascular assessment for PAD

Answer 9

includes pulse palpitation, auscultation for femoral bruits, and inspection of the legs and feet

Question 10

How to confirm Diagnosis of PAD

Answer 10

abnormal physical examination findings must be confirmed with diagnostic testing
-other comorbid causes of atypical leg pain should be ruled out before diagnosing

Question 11

Non-invasive testing for PAD

Answer 11

-ankle-brachial index (ABI)
-plethysmography
-graded-exercise treadmill test
>provide information about the arterial system with minimal risk

Question 12

Ankle-Brachial Index (ABI)

Answer 12

used a doppler probe to compare the BP obtained at the ankle with the pressure obtained at the brachial artery

• BP readings are normally higher in the ankle than those in upper extremities
• test provides a ratio known as ABI; value can be derived by dividing the ankle BP by the brachial BP
• ABI less than 0.9 in either leg is diagnostic of PAD

Question 13

Ankle-Brachial Index Values

Answer 13

• Greater than 1.30= non-compressible arteries (stiff arteries)
• 1 to 1.29= normal
• 0.91 to 0.99= borderline PAD
• 0.41 to 0.9= mild to moderate PAD
• 0 to 0.4= severe PAD

Question 14

Plethysmography

Answer 14

non-invasive test used to evaluate arterial flow in the lower extremities

• pulse volume recordings are plethysmographical tracings that detect changes in the volume of blood flowing through a limb
• pressure cuffs are placed on the thigh, calf, ankle, or foot
• the pressure cuffs are inflated to 65 mm Hg and a plethysmographical tracing is recorded at the various areas where the cuffs are placed
• a normal pulse volume recording is similar to a normal arterial pulse wave tracing and consists of a rapid systolic upstroke and rapid downstroke with a prominent dicrotic notch.
• with increasing severity of PAD, the waveforms are decreasing or flattening depending on the degree of occlusion

Question 15

Treadmill Test

Answer 15

give valuable information about the degree of peripheral arterial narrowing in patients who experience intermittent claudication

• once the resting pressure and pulse volumes are obtained, the patient is asked to walk on a treadmill at a constant speed, either at a constant grade or with a variable incline (lasts for 5 minutes)
  1. confirms the diagnosis of intermittent claudication and PAD
  2. demonstrates the objective functional limitation of PAD
  3. documents the effect of therapy on initial and absolute claudicating distances
  4. uncovers previously unrecognized coronary artery disease

Question 16

Duplex Ultrasound

Answer 16

uses the detection of sound waves to measure the velocity of blood flow
-used to detect and localize vascular lesions and quantify the amount and severity of damage through blood flow velocity criteria

Question 17

Stages of PAD

Answer 17

• Stage I: Asymptomatic PAD
• Stage II: claudication
• Stage III: Rest Pain
• Stage IV: Necrosis or gangrene

Question 18

Stages of PAD: Stage I: Asymptomatic PAD

Answer 18

• no claudication/ pain is experienced by patient
• bruit may be heard
• pedal pulses are decreased or absent

Question 19

Stages of PAD: Stage II: Claudication

Answer 19

• muscle pain, burning and cramping are experienced with exercise and are relieved by rest
• pain is reproducible with the same amount of exercise

Question 20

Stages of PAD: Stage III: Rest Pain

Answer 20

• pain is experienced at rest
• pain often awakens patient at night
• pain is described as numbness and burning and usually occurs in the distal portion of the extremity
• pain is often relieved by putting the extremity in the dependent position

Question 21

Stages of PAD: Stage IV: Necrosis or gangrene

Answer 21

• ulcers and blackened tissue occur on the toes, the forefoot, or the heel of the foot
• gangrenous odor may be present

Question 22

Computed tomography angiography (CTA)

Answer 22

is a CT scan that requires contract material to visualize blood vessels

• it displays the roadmap of the vasculature which identifies the issues and is sometimes essential for determining interventional strategies
• Advantages: quick non-invasive testing, wide availability, high resolution, and 3D imaging
• Disadvantages: lack of hemodynamic data, exposure to radiation, use of contrast agents

Question 23

Magnetic Resonance Angiography (MRA)

Answer 23

magnetic resonance test that focuses on the study of the vasculature

• uses contrast and non-contrast techniques when imaging the peripheral arteries
• Non-contrast MRA has inferior resolution and may contain artefacts that limit interpretation, but is a valuable alternative for use in patients with mild to moderate chronic kidney disease for whom se of contrast agents is not recommended
• vascular calcification can be underestimated by MRA and may affect revascularization procedures

Question 24

Angiography

Answer 24

consists of arteriography of the lower extremities

• done to quantify the narrowing of the occluded vessels
• arteriography involves injecting contrast medium into the arterial circulation through a small sheath in the groin
• treatment options can be derived and refined via arteriography; one treatment option is balloon angioplasty for the occluded vessel with stent placement
• angiography can also provide a better visual for refinements for planned peripheral bypass surgery

Question 25

Treatment

Answer 25

goal is to provide relief of symptoms, prevent the progression of arterial disease and cardiovascular complications, improve quality of life, and provide education about the disease

• medications and non-surgical and surgical interventions are options
• non-pharmacological interventions such as weight reduction, smoking cessation, exercise, and adherence to a low-fat diet are first line actions

Question 26

Medications

Answer 26

target the risk factors driving the progression of atherosclerosis in PAD

• antihypertensive, antiplatelet, and statin agents
• Beta blockers can be used for BP control

Question 27

Medications: Antiplatelet

Answer 27

acetylsalicylic acid (aspirin) and clopidogrel (Plavix) are prescribed in patients with chronic PAD
-inhibit platelet aggregation, therefore decreasing the probability of vascular events

Question 28

Medications: Lipid-Lowering Statins

Answer 28

successfully reduce total cholesterol in most patients when used for extended period
-Achieve target LDL-C level of less than 100 mg/dL

Question 29

Nonsurgical Management

Answer 29

consists of positioning or promoting vasodilation by having limb in a dependent position

• exercise; to increase blood flow to affected limb by increasing collateral circulation
• percutaneous transluminal angioplasty, laser-assisted angioplasty, rotational atherectomy

Question 30

Nonsurgical Management: Percutaneous transluminal angioplasty

Answer 30

nonsurgical, minimally invasive method of improving arterial blood flow

• a cannula is inserted into or above an occluded or stenosed artery
• the occluded artery is then dilated with a balloon catheter
• success is proven when it opens the vessel and restores or improves arterial blood flow
• stents may be used to keep vessels open
• transfemoral approach is safest; alternative brachial or axillary

Question 31

Nonsurgical Management: Laser-assisted angioplasty

Answer 31

minimally invasive intervention for patients with PAD

• a laser probe is advanced through a cannula that is inserted into or above an occluded artery
• usually indicated for smaller occlusions in the distal superficial femoral, proximal popliteal, and common iliac arteries
• heat from the laser probe vaporizes the arteriosclerotic plaque to open the occluded or stenosed vessel

Question 32

Nonsurgical Management: Rotational Atherectomy

Answer 32

used to improve blood flow to the ischemic limbs of people with PAD

• more commonly used for very hard, calcified stenotic lesions that are not amenable to balloon angioplasty
• rather than compressing plaque and stretching an artery narrowed by atherosclerotic plaque, the goal is removal of the plaque by breaking it into micro fragments which can pass harmlessly into the circulation

Question 33

Surgical Management

Answer 33

surgical or revascularization is indicated when patients have severe pain at rest or claudication that interferes with ADLs
-arterial revascularization through bypass grafting
-surgical bypass treats narrowed arteries by creating a bypass around a section of the artery that is blocked
(autogenous grafts; patients own saphenous vein or synthetic grafts if patients own vessels are not available)

Question 34

Complications

Answer 34

• Critical Limb Ischemia

- Acute Limb Ischemia

Question 35

Complications: Critical Limb Ischemia

Answer 35

sustained, severe decrease of arterial blood flow to the affected extremity, which leads to chronic ischemia, rest pain, ulceration, gangrene, and limb loss if left untreated

• obstructive atherosclerotic arterial disease is the most common cause of this
• presents after extended course of PAD
• once PAD progresses to CLI the prognosis is generally poor; infection, cellulitis, and tissue breakdown can occur; all of which increase the requirement for oxygenated blood, which is decreased because of the disease process
• without adequate tissue perfusion, tissue breakdown and ulcers worsen, and gangrene becomes apparent; need revascularization to save the limb

Question 36

Complications: Acute Limb Ischemia

Answer 36

sudden decrease in blood flow to an extremity that threatens tissue viability
-be the first manifestation of PAD in a previously asymptomatic patient or caused by an acute event that leads to symptomatic deterioration in a patient
with lower extremity PAD and intermittent claudication

Question 37

What is the most common cause of peripheral occlusions

Answer 37

-embolus

Question 38

Acute Limb Ischemia Clinical Manifestations

Answer 38

“six Ps”

• pain
• pallor
• pulsenessless
• paresthesia (pins and needles, tingling)
• paralysis
• poikilothermia (cool)

Question 39

Goal of treatment for Acute Limb Ischemia

Answer 39

preserve tissue and save the limb

• initiation of anticoagulation therapy with IV heparin is usually the first intervention to prevent further clot formation
• other interventions: restore blood flow, which relieves pain, helps heal ulcers, and possibly prevents amputation

Question 40

Clinical Manifestations of Severe PAD

Answer 40

• extremity is cold and cyanotic or darkened
• pallor may occur when extremity is elevated and dependent redness may occur when extremity is lowered
• muscle atrophy can also accompany prolonged PAD

Question 41

Nursing Diagnosis

Answer 41

• ineffective peripheral tissue perfusion r/t interruption of arterial blood flow to the peripheral tissue
• risk for impaired skin integrity r/t altered circulation or sensation
• chronic pain r/t decreased peripheral perfusion e/b the inability to walk for prolonged periods of time or having pain at rest

Question 42

Nursing Interventions: Assessment

Answer 42

• assess bilateral BP (increased risk of subclavian artery stenosis. upper arm BP difference greater than 15 to 20 mm Hg is abnormal and suggestive of subclavian stenosis. use bigger BP measurement when calculating ABI and titrating blood pressure medications)
• Palpate pulses in both legs (weak or absent pulses indicate poor blood flow through the extremity)
• Visual Assessment of feet and limbs (signs of ulcer formation, sluggish capillary refill, dry, scaly, dusky, pale, or mottled skin, thickened toenails, loss of hair on lower calf, ankle, and foot indicate poor peripheral blood flow)
• Temperature (cool or cold temp in extremities indicates poor flow)
• Assess bilateral muscle tone (muscle atrophy can accompany prolonged chronic arterial disease)
• Assess pain

Question 43

Nursing Intervetions: Actions

Answer 43

• administer medications as ordered (anti-hypertensives, antiplatelet agents, Cilostazol (has antiplatelet and vasodilation properties that can improve PAD)
• proper positioning (keep extremity dependent)

Question 44

Nursing Interventions: Teaching

Answer 44

• positioning (avoid crossing legs)
• Inspect feet daily
• report chest discomfort or neurological changes
• lifestyle changes consistent with management of atherosclerosis: DASH diet, limit alcohol, smoking cessation, moderate exercise