Chp. 30

Arteriosclerosis and Atherosclerosis

  • Definitions
      - Arteriosclerosis:
        - Hardening of the vessel wall
        - Accompanied by thickening
        - Often associated with aging
      - Atherosclerosis:
        - A type of arteriosclerosis characterized by plaque formation on arterial walls.
        

  • Key Differences
      - Arteriosclerosis involves the thickening and hardening of vessels.
      - Atherosclerosis involves plaque formation on the arterial wall.

  • Clinical Implications
      - Both conditions can decrease blood flow, leading to decreased perfusion.
      - Atherosclerosis poses risks such as plaque rupture and subsequent clot formation causing ischemia.

Plaque Characteristics

  • Types of Plaques
      - Stable Plaque:
        - Less likely to rupture.
      - Unstable Plaque:
        - Prone to rupture, requiring intervention.

Patient Assessment Techniques

  • Pulse Palpation:
      - Check pulses bilaterally for equality.

  • Capillary Refill:
      - Examine refill time as an indicator of perfusion.

  • Skin Temperature:
      - Cool skin may indicate poor arterial perfusion.
      - Warm skin may suggest venous issues.

  • Bruits:
      - Abnormal whooshing sounds that indicate turbulent blood flow.
      - Especially monitor carotid arteries.

Risk Factors for Atherosclerosis

  • Lifestyle Factors
      - Smoking
      - Sedentary lifestyle
      - Poor diet (high saturated fat and cholesterol)

  • Demographics
      - Older adults, particularly African American and Hispanic populations

  • Medical Conditions
      - Diabetes
      - Obesity
      - Hypertension

Dietary Recommendations

  • Saturated Fats:
      - Limit to 5-6% of daily caloric intake.

  • Trans Fats:
      - Avoid entirely.

  • Other Dietary Adjustments:
      - Include low-fat dairy, poultry, fish, legumes, non-tropical oils.
      - Limit intake of sweets, sugars, and red meats.

Pharmacological Treatments

  • Medications
      - Niacin: A B vitamin.
      - Lovaza: Contains omega-3 fatty acids, lowers triglyceride levels.
      - Statins (HMG CoA reductase inhibitors):
        - Lower total cholesterol.
        - Monitor liver enzymes every six months.
        - Avoid grapefruit juice which can lead to statin accumulation.
      - Ezetimibe:
        - Inhibits intestinal cholesterol absorption.
      - PCSK9 Inhibitors (e.g., Repatha):
        - Expensive but effective in lowering LDL cholesterol.
        - Administered via injection, typically bi-weekly or monthly.

Peripheral Artery Disease (PAD)

  • Definition:
      - Result of systemic atherosclerosis affecting peripheral arteries.

  • Diagnostic Tests:
      - Ankle-Brachial Index Test: measures blood flow.

  • Symptoms:
      - Intermittent claudication: pain in lower legs, potentially at rest.
      - Hair loss, dry/scaly skin, ulcers on toes.
      - Loss of pulse detection may require Doppler ultrasonography.

Types of Arterial Ulcers

  • Arterial Ulcers: Found on toes, display specific characteristics.

  • Management: Build collateral circulation through lifestyle changes (e.g., avoiding leg crossing).
      - Emphasize the importance of inspecting feet daily.

Surgical Procedures for PAD

  • Percutaneous Vascular Intervention:
      - Angioplasty with stenting to open blocked arteries.

  • Bypass Surgery:
      - Graft placement to bypass occluded arteries.

Complications Post-Procedure

  • Monitor for:
      - Bleeding, perfusion issues, and signs of clot formation.

  • Six P's of Ischemia:
      - Pain, pallor, pulselessness, paresthesia, paralysis, and poikilothermia (coolness).

Aneurysms

  • Definitions:
      - Permanent dilation of an artery, at least twice its normal size (e.g., thoracic, abdominal).

  • Possible Symptoms:
      - Gnawing pain in abdomen or back, possible bulge felt in abdomen.

Diagnosis of Aneurysms

  • Imaging Techniques: CT scans, ultrasound, patient assessment for bruises and abnormal findings.

  • Emergency response: Immediate action for ruptured aneurysms is necessary, often involving surgical intervention.

Post-Surgical Management

  • Activity Restrictions:
      - Limit lifting and strenuous activities for several weeks.

  • Monitoring Symptoms:
      - Watch for signs of leaks or complications following surgical procedures.

Venous Disease Overview

  • Primary Focus: Prevention of thrombus formation, i.e., DVT, and associated complications like PE.

  • Contributing Factors (Bershaw's Triad):
      - Stasis of blood, endothelial injury, hypercoagulability.

DVT Assessment and Management

  • Symptoms: Swelling, pain, warmth in the affected leg.

  • Diagnostic Tools: Venous duplex ultrasound and D-dimer testing.

  • Management Strategies: Anticoagulant therapy, ambulation, and use of compression stockings.

Understanding Anticoagulant Therapy

  • Types of Anticoagulants:
      - Heparin: monitor platelet counts and potential complications.
      - Warfarin: monitor INR values, patient education on vitamin K and dietary consistency.
      - Direct Oral Anticoagulants (DOACs) are also common.

Surgical Interventions for DVT

  • Thrombectomy: rarely done but used in severe cases.

  • Inferior Vena Cava Filter: Used to trap clots for patients at high risk of DVTs who cannot take anticoagulants.

Venous Insufficiency and Ulcers

  • Stasis Dermatitis: A common issue resulting from reduced blood flow.

  • Management: Compression therapy, elevating the legs, and ensuring proper wound care including nutrition.

Varicose Veins Treatment Options

  • Sclerotherapy and Stripping: Used primarily for cosmetic reasons or pain management.

  • Endovenous Ablation: A minimally invasive alternative with postoperative requirements for compression therapy.