Exam 22 - Peripheral Vascular System Disorders

• Disorders of the Peripheral Vascular System can be broken down into effects of aging, risk factors, assessment, diagnostic testing, hypertension, and arterial or venous disorders.

Effects of Aging on the Peripheral Vascular System

• Degenerative changes are a normal part of aging
• Blood vessel walls thicken and become less flexible
• Decreased elasticity of blood vessels leads to increased peripheral vascular resistance, higher blood pressure, and increased risk of PVD

Risk Factors for Peripheral Vascular Disease (PVD)

• Non-modifiable risk factors include age, gender, and family history
• Vascular resistance increases with age due to arteriosclerotic changes
• Men are more susceptible to PVD until women experience menopause
• A family history of atherosclerosis increases the risk of PVD
• Modifiable risk factors include smoking, hypertension, hyperlipidemia, obesity, lack of exercise, emotional stress, and diabetes mellitus
• Smoking causes vasoconstriction, elevates blood pressure, and reduces circulation
• Hypertension causes wear and tear on vessels, leading to narrowing and increased resistance
• Hyperlipidemia contributes to plaque buildup
• Obesity increases workload on the heart and blood vessels
• Lack of exercise leads to loss of muscle tone, affecting venous return
• Emotional stress may increase blood pressure, cholesterol, and vasoconstriction
• Diabetes Mellitus, or elevated glucose levels contribute to atherosclerosis

Peripheral Vascular System Assessment

• Arterial assessment findings include pain, pulses, capillary refill, edema, skin, and color
• Pain may manifest as intermittent claudication (cramp-like pain during activity) or pain at rest, indicating chronic disease
• Pulses may be weak, thready, or absent
• Capillary refill may be more than 2 seconds
• Edema is usually absent
• Skin may be dry, shiny, and hairless, and cool or cold to the touch
• Color may exhibit pallor with elevation or erythema with dangling
• Venous assessment findings include pain, pulses, edema, skin, and ulceration
• Pain may be aching and cramping, relieved by activity or elevation
• Pulses are usually present
• Edema is present due to venous insufficiency
• Skin may exhibit darker pigmentation, dryness, scaling, and tough areas
• Stasis ulcers may be present
• Assessment Tools include the Five P's (Arterial Occlusion) and PATCHES
• The Five P's (Arterial Occlusion) are pain, pallor, pulselessness, paresthesia, and paralysis
• PATCHES (Arterial or Venous) includes pulses, appearance, temperature, capillary refill, hardness, edema, and sensation
• Pulses should be assessed affected extremity first and compared bilaterally, using Doppler ultrasound if needed
• Appearance includes color (pale, mottled, cyanotic, or discolored), necrosis, bleeding, and ulcers (size, depth, location, edges)
• Temperature: Arterial extremity feels cool while venous extremity feels normal or warm
• Capillary Refill should be <2 seconds; prolonged in PVD
• Hardness indicates longstanding PVD and increased risk of stasis ulcers
• Edema may be pitting (acute) or non-pitting (chronic); Measure circumference of affected and unaffected extremity
• Sensation should be assessed for pain, numbness, tingling, and tenderness

Diagnostic Testing for PVD

• Non-Invasive Procedures includes treadmill test, plethysmography, Doppler ultrasound, and duplex scanning
• A treadmill test evaluates blood flow after exercise and identifies claudication
• Plethysmography measures changes in blood volume in extremities
• Doppler ultrasound measures blood flow in arteries or veins and assesses intermittent claudication and deep vein obstruction
• Duplex scanning uses ultrasound and Doppler to locate thrombi in veins (diagnoses DVT)
• Pulsation used with palpate when assessing
• Invasive procedures includes phlebography/venography, I-fibrinogen uptake test, angiography, D-dimer, and digital subtraction angiography (DSA)
• Phlebography/Venography is the gold standard for assessing deep leg veins and diagnosing DVT; contrast medium is used to detect filling defects
• I-fibrinogen Uptake Test detects acute calf vein thrombosis where fibrinogen tagged with iodine 125 is used
• Angiography uses contrast medium to visualize arteries via radiography
• D-dimer is a serum test for fibrin degradation product elevated levels indicate thrombus
• Digital Subtraction Angiography (DSA) uses intravenous contrast solution that visualizes blood vessels via radiography

Hypertension

• Hypertension is a risk factor in atherosclerosis and PVD
• Blood pressure classifications ranges from normal to hypertensive crisis
• Normal is <120 mmHg systolic and <80 mmHg diastolic
• Hypertension is >140 mmHg systolic or >90 mmHg diastolic
• Stage I hypertension is 140-159 mmHg systolic or 90-99 mmHg diastolic
• Stage II & III hypertension is >160 mmHg systolic or >100 mmHg diastolic
• Hypertensive crisis is >180 mmHg systolic or >110 mmHg diastolic (requires emergency care)
• Pre-hypertension is 120-139 mmHg systolic or 80-89 mmHg diastolic
• A diagnosis of hypertension is based on an average of two or more elevated readings on separate occasions
• Factors determining arterial blood pressure are blood flow and peripheral vascular resistance
• Blood flow is the amount of blood pumped per heartbeat
• Peripheral vascular resistance is vessel diameter and blood viscosity
• Regulation of blood pressure occurs via sympathetic nervous system and the renin-angiotensin-aldosterone system (RAAS)
• The sympathetic nervous system regulates blood pressure where epinephrine and norepinephrine cause vasoconstriction
• Decreased blood flow to kidneys activates RAAS system
• Renin converts angiotensinogen to angiotensin I
• Angiotensin I converts to angiotensin II
• Angiotensin II stimulates aldosterone release, causing sodium and water retention and vasoconstriction
• Classifications of hypertension include essential (primary) and secondary
• Essential (primary) hypertension has an unknown cause in 90-95% of cases
• Theories of essential hypertension include arteriolar changes, sympathetic nervous system activation, hormonal influence, genetic factors, weight, lifestyle, sodium intake, and alcohol intake
• Non-modifiable risk factors include age, gender, race(African Americans), and family history
• Modifiable risk factors include smoking, obesity, high-sodium diet, elevated cholesterol, oral contraceptives/estrogen therapy, alcohol, stress, and sedentary lifestyle
• Secondary hypertension is attributed to identifiable medical diagnosis
• Conditions contributing to Hypertension include renal vascular disease, adrenal cortex disease, coarctation of aorta, head trauma, pregnancy
• Malignant hypertension is a rapidly progressing elevation in blood pressure (diastolic > 120 mm Hg)
• Untreated hypertension leads to fibrous tissue replacing elastic tissue in arterioles, decreasing tissue perfusion in heart, kidneys, and brain
• Malignant hypertension damages arterioles in heart, kidney, brain, and eyes
• Can be common in African American men <40 years old
• Medical Management Goals include blood pressure measures and medications based on severity, risk factors, and organ damage

Arterial Disorders

• Arteriosclerosis/Atherosclerosis includes arterial thickening, plaque buildup, lack of oxygen, and common complications
• Arteriosclerosis involves thickening, loss of elasticity, and calcification of arterial walls
• Atherosclerosis involves plaque buildup in arteries, leading to narrowing
• Ischemia occurs when oxygen demand exceeds supply, leading to cell death
• Common complications include obstruction, thrombosis, aneurysm, and rupture
• Arteriosclerosis Obliterans is when plaque forms on the vessel wall, causing occlusion
• Tissue demand exceeds blood supply, causing claudication.
• Clinical Manifestations: Five P's of arterial occlusion
• Subjective: Pain with activity relieved by rest; and pain at rest
• Objective: Weak or absent pulses, pale, hairless, shiny skin
• Prognosis: Ischemia may lead to necrosis, ulceration, and gangrene
• Arterial Embolism is blood clots or foreign substances that block arterial blood flow
• Clinical Manifestations: Severe pain, absent distal pulses, pale, cool, and numb extremity, necrotic changes, shock
• Arterial Aneurysm include: Enlarged, dilated portion of an artery due to arteriosclerosis, trauma, or congenital defect
• Clinical Manifestations:
• Large, pulsating mass
• Thoracic: Chest pain, shortness of breath, cough, hoarseness, dysphagia, edema of face, neck, and arms
• Abdominal: Pain in chest, lower back, or scrotum
• Buerger's Disease (Thromboangiitis Obliterans): Inflammation and thrombosis of small and medium-sized arteries; related to tobacco use
• Clinical Manifestations: Pain in arch of foot with exercise, cold and pale extremities, ulcers and gangrene, sensitivity to cold, superficial thrombophlebitis
• Raynaud's Disease is intermittent arterial spasms causing ischemia; is intermittent arterial spasms causing ischemia in fingers, toes, ears, and nose when triggered by cold or emotional stimuli
• Manifestations of Raynaud's include chronically cold hands and feet, pallor, coldness, numbness, cyanosis, pain, and ulcerations

Venous Disorders

• Nursing priorities focus on promoting tissue healing, promoting comfort, maintaining peripheral tissue perfusion, preventing infections, and patient teaching when treating Peripheral Venous Disease
• Thrombophlebitis is venous stasis, hypercoagulability, trauma to vessel wall
• Pain and edema occur when the vein is obstructed, increased calf and thigh circumference, erythema, warmth, and tenderness along course of vein
• Varicose Veins include vessel wall weakens and dilates, stretching valves and resulting in an inability of vessel to support a column of blood result is blood pooling in veins or varicosities (venous stasis)
• Venous Stasis Ulcers: Deep vein insufficiency and blood stasis in leg veins.
• Ulcer manifestations include varying degrees of pain, from mild to dull ache, which may be relieved by elevation of extremity, visibly ulcerated skin, most often on the medial aspect of the ankle, with dark pigmentation