Module 2.4 - Peripheral Vascular Disease Flashcards
1
Q
What is a peripheral vascular disease?
A
- Peripheral vascular disease is defined as disorders of both the peripheral arteries and veins. It affects approximately 1 in every 5 adults with increased prevalence with age.
- In patients > 70 years of age, the chance of developing peripheral vascular disease (PVD) is increased by 15-20%. It often coexists in those patients that have other atherosclerotic diseases such as CAD.
- It has a strong association with Diabetes Mellitus and smoking. (the strongest risk factors for PVD). Older patients with long-standing diabetes and evidence of neuropathy are at highest risk for this disease.
- PVD includes both arterial and venous manifestations (Peripheral arterial disease & chronic venous insufficiency)
2
Q
What is peripheral artery disease?
A
- PAD generally refers to atherosclerotic occlusive disease in the arteries of the lower extremities primarily
- It may be silent or present with a variety of symptoms and signs indicative of extremity ischemia
- Severe PAD may cause rest pain with skin atrophy, hair loss, cyanosis, ischemic ulcers and gangrene.
- Diminished or absent pulses along with arterial bruits may be present.
- Will eventually lead to peripheral artery obstruction
3
Q
What are the subjective/physical findings associated with PAD?
A
- Pain – intermittent claudication (i.e., pain to calf, thigh, or buttock when walking) Pain that awakens them from their sleep? The relationship of pain location and corresponding anatomy of the occlusive disease is as follows:
- Pallor – changes in extremity appearance depends on the duration and severity of PAD. Patients with significant PAD have significant pallor, patients with chronic arterial occlusion may have intensified skin color due to compensatory arteriole dilation in response to ischemia
- Pulses – absent or diminished distal to the obstruction. A good exam includes palpation of the brachial, radial, femoral, popliteal, dorsalis pedis and posterior tibial arteries.
- Paresthesia – chronic ischemia can cause varying patterns of sensory loss
- Paralysis
- Poikilothermia – unable to maintain temperature; cold. Temperature of the skin is an indicator of flow in the dermal vessels and is a useful marker of perfusion
- Bruits over a narrowed artery
- Loss of hair on toes or lower extremity
- Glossy, thin skin
- Peripheral edema
4
Q
What are Rutherford’s Categories of PAD
A
- Stage O – asymptomatic
- Stage 1 – mild claudication
- Stage 2 – Moderate claudication with distance
- Stage 3 – Severe claudication
- Stage 4 – rest pain
- Stage 5 – Ischemic ulceration not exceeding ulcer of the digits of the foot
- Stage 6 – Severe ischemic ulcers or frank gangrene
5
Q
What diagnostic tests can be used for PAD?
A
- Ankle-Brachial index (ABI)
- Doppler ultrasonography - does not accurately visualize arterial anatomy
- Duplex ultrasonography - accuracy diminished in obese patients
- Treadmill testing – measure ABI post exercise, decline suggests PAD
- Magnetic resonance angiography (MRA) – contraindicated in patients with implanted metal devices, stents, clips, coils
- Computed tomographic angiography (CTA) - can be used if MRA contraindicated. Must be mindful of iodine dye in allergic patients and dye load effect on kidneys, particularly in the elderly
- Contrast angiography – definitive study, hemodynamic significance of stenosis can be determined at the time, the lesion can be corrected. Has more side effects: potential bleeding infection, contrast nephropathy from iodine dye
6
Q
What is an Ankle-Brachial index (ABI)?
A
- It is defined as the ratio of the SBP in the ankle divided by the SBP at the arm.
- This is the best diagnostic test for PAD.
- Normal reading is 1.0 -1.3.
- Readings less than 1.0 suggest PAD
- Patients with long standing diabetes, chronic renal failure and/or the elderly may have ABI > 1.3 due to dense calcified vessels.
7
Q
What supportive measures are used in patients with PAD?
A
- Meticulous foot care
- Protective shoes to prevent trauma
- No constrictive sock wear to decrease blood flow
- Exercise program/therapy – increases blood flow that may improve claudication. Improves muscular strength and endurance, induces vascular angiogenesis and reduces red blood cell aggregation and viscosity.
8
Q
What medications are used patients with PAD?
A
Platelet inhibition aggregation medications are given to induce vasodilation:
- Pletal 100 mg PO BID or Trental 400 mg TID
- Aspirin 81-325 mg QD or Clopidogrel (Plavix) 75 mg PO QD
9
Q
What interventions are left for patients if supportive measures and medications have failed to manage PAD?
A
Revascularization:
For those patients with progressive disease and worsening functional status that have failed medical management, a refer to a vascular specialist is warranted for consideration of:
- Percutaneous intervention
- Surgical Bypass
10
Q
What are the goals of care for PAD management?
A
- Diabetes Control
- Smoking cessation (complete)
- Hypertension management
- HLD management
- Age – greatest risk is for those > 70 years of age.
11
Q
What causes Arteriosclerosis obliterans?
A
- Stenosis or occlusion of the arterial lumen that results from atherosclerosis
- May form acutely or be a chronic condition
- Increased incidence in men (3:1), mostly seen between 50-70 years of age and in patients with diabetes
12
Q
Describe the findings associated with acute limb ischemia due to Arteriosclerosis obliterans and how is it managed?
A
- Findings: Acute and sudden severe pain, paresthesia, numbness, coldness with loss of distal pulses, cyanosis and coolness. Reflexes can also be decreased
- Management: initiate anticoagulation with IV heparin immediately, may need revascularization, intra-arterial thrombolysis with TPA or surgical intervention for thromboembolectomy
13
Q
What is thromboangitis obliterans (Buerger’s disease)?
A
- Non atherosclerotic inflammatory vasculopathy involving small and medium sized arteries and veins in the distal upper and lower extremities caused by an inflammatory and highly cellular intraluminal thrombus.
- It is more common in men, in Asians and Eastern Europeans. It is rarely seen in women. Smoking increases the possibility of this disease.
- exact etiology is unknown, immune system plays a central role and smoking worsens the condition. May have a genetic disposition.
14
Q
What are the 3 phases of Thromboangiitis obliterans (Buerger’s disease)?
A
- Acute – inflammation occurs quickly, thrombosis and subsequent abscesses are possible
- Intermediate – Progressive development of thrombus, less inflammation
- Chronic – end stage lesion with occlusive thrombus and fibrosis
15
Q
What are some subjective/physical findings associated with Thromboangiitis obliterans (Buerger’s disease)?
A
- can include pain with walking (intermittent claudication) and at rest, coldness, pallor and decreased pulses.
- Can progress to ulcerations
17
Q
What is and what causes Chronic Venous Insufficiency (CVI)?
A
Results from venous outflow disturbance of the limbs. It may or not be associated with venous valvular insufficiency and involves the superficial and/or deep venous system of the lower extremities.
18
Q
What are some subjective/physical findings associated with Chronic Venous Insufficiency (CVI)?
A
- Aching legs, worse with standing
- Tingling, burning, muscle cramps
- Restless legs
- Fatigue
- Dependent edema
- Shiny, taut skin
- Brown blotches, color changes – stasis dermatitis
- Ulcerations or varicose veins
19
Q
What diagnostic tests are used for Chronic Venous Insufficiency (CVI)?
A
- Venous Duplex - confirms the diagnosis of CVI and assesses it’s etiology and severity
- Photoplethysmography - assesses the physiological function. Venous refill time < 18-20 seconds is indicative of CVI
- Phlebography or venography - includes assessments of venous reflux (incompetent valves) and obstruction
- Computed tomography and magnetic resonance venography - can identify venous obstruction in pelvis or iliac system
- Intravascular Ultrasound - evaluate venous compression or obstruction
