Peripheral Vascular Notes

Peripheral Vascular System

Objectives

• Understand surgical procedures, techniques, and special considerations in peripheral vascular interventions.
• Identify the reasons for surgical intervention in peripheral vascular conditions.

Anatomy of Peripheral Vessels

• Major Arteries:
  • Carotid artery
  • Subclavian artery
  • Aorta
  • Renal artery
  • Iliac artery
  • Femoral artery
  • Popliteal artery
  • Tibial artery

Peripheral Vascular System Defined

• Includes all blood vessels outside the heart.
• Consists of the aorta and its branches.
• Arteries: Nourish organs with blood and nutrients; operate under high pressure.
• Arterioles: Respond to tissue needs for nutrients/oxygen.
• Capillaries: Thin-walled vessels where nutrient and metabolite exchange occurs primarily via diffusion.
• Venules: Smallest veins receiving blood from capillaries, involved in oxygen and nutrient exchange for waste products.
• Veins: Contain one-way valves to ensure forward blood flow towards the heart.

Peripheral Vascular Disease (PVD)

• Characterized by reduced blood circulation to body parts (excluding brain/heart) due to:
  • Narrowed vessels (stenosis)
  • Blocked vessels (occlusion)
  • Abnormal enlargements (pseudoaneurysm)
• Risk Factors:
  • Diabetes
  • Obesity
  • Smoking
  • Aging
  • Sedentary lifestyle
• Atherosclerosis is a leading cause of death and disability in the Western World.

Aneurysm

• True Aneurysm: Weakening and bulging of the vessel wall forming a blood-filled sac, vessel wall not injured.
• Causes: Exact cause unknown, potential factors include:
  • Atherosclerosis
  • High blood pressure
  • Family history
  • Older age
  • Smoking
  • Diabetes
  • Obesity
  • High cholesterol
  • Illicit drug use
  • Pregnancy
  • Trauma to the head or brain
• Complications:
  • Rupture leading to internal bleeding and death.
  • May be asymptomatic.
• Types:
  • Abdominal Aortic Aneurysm (AAA)
  • Brain aneurysms: Often small and asymptomatic; may be discovered incidentally.
• Treatment: Open surgery or endovascular repair with a graft.

Abdominal Aortic Aneurysm (AAA)

• Bulge in the wall of the aorta within the abdomen.
• Development Factors:
  • Atherosclerosis (weakens aorta wall)
  • Age (over 60)
  • Smoking
  • High blood pressure
  • High cholesterol
  • Family history
  • Genetic conditions
• Endovascular AAA Repair (EVAR): Minimally invasive procedure involving catheter insertion and stent graft placement.

Pseudoaneurysm

• Collection of blood outside an artery or the heart due to a damaged vessel wall.
• Damage pierces all three layers, forming a weak "wall".
• Causes:
  • Artery injury
  • Infection
  • Aneurysm rupture
  • Surgery
  • Trauma
• The wall consists of products from the clotting cascade.

Bypass Surgery

• Involves using a graft (vessel from another part of the body) to bypass a blockage in an artery.
• Types:
  • Coronary Artery Bypass Graft (CABG)
  • Femoral-Popliteal (Fem-Pop) Bypass
• Graft Sources:
  • Saphenous vein (leg)
  • Synthetic tube
  • Xenograft (bovine)

Thrombectomy

• Removal of a blood clot from a blood vessel to restore blood flow.
• Performed via open surgery or endovascular repair.
• Indications:
  • Stroke
  • Acute Myocardial Infarction (MI)
• Risk Factors:
  • Immobility
  • Injury
  • Disease
  • Certain medications
  • Obesity
  • Family history of blood clots
  • Age
  • Pregnancy
  • Recent surgery

Embolectomy

• Surgical procedure to remove an embolus (blood clot) from a blood vessel.
• Often an emergency procedure.
• Types:
  • Catheter embolectomy (minimally invasive)
  • Surgical embolectomy (open heart surgery)

Endarterectomy

• Surgical removal of plaque buildup from the lining of an artery to improve blood flow and reduce the risk of clots/stroke.
• Incision made to be able to remove fatty deposits and artery is then closed with stitches or a patch, this takes approximately 1-2 hours with local/general anesthesia.
• Types:
  • Carotid: Removes plaque from arteries in the neck leading to the brain.
  • Femoral: Removes plaque from arteries in the groin leading to the legs.
  • Aortic and Iliac: Removes plaque from main arteries in the abdomen and pelvis.

Shunt

• A small plastic tube used to divert blood around the section of the carotid artery during surgery.
• Usage based on surgeon preference and brain blood flow monitoring.

Amputation

• Surgical removal of a limb or part of a limb.
• Causes:
  • Accident or injury
  • Blood vessel disease
  • Cancer
  • Infection
  • Excessive tissue damage
  • Dysfunction
  • Pain
• Anesthesia: General, epidural, or spinal.
• Complications:
  • Joint deformity
  • Hematoma
  • Wound opening
  • Tissue death
  • Continuing pain
  • Phantom limb phenomena
  • Emotional trauma
  • DVT (Deep Vein Thrombosis) or PE (Pulmonary Embolism)

Angioplasty

• Procedure involving insertion of an inflatable balloon to widen a narrowed blood vessel by pushing plaque against the wall.
• Can be open or percutaneous transluminal.
• Used in emergencies like heart attacks.

Stents

• Tube-shaped device inserted into a vessel to keep it open.
• Used for weak or narrowed vessels.
• Made of polymer or metallic alloy mesh.
• Often used with angioplasty to treat heart attacks, angina, and carotid artery disease.

Arteriovenous Fistula (AV Fistula)

• Abnormal connection between an artery and a vein, bypassing capillaries.
• Leads to decreased blood flow to tissues below the fistula.
• Dialysis Fistulas: Surgically created for hemodialysis access.

Fistulogram

• X-ray procedure using contrast to look for abnormalities in dialysis grafts or AV fistulas.
• Detects abnormal connections of vessels in tissues around the brain or spinal cord.
• Arteries directly connected to veins or venous spaces (sinuses).

Varicose Veins

• Swollen, twisted veins just under the skin (also known as varicoses or spider veins).
• Caused by faulty valves and or weak walls within veins that allow blood to pool.
• Standing for too long without activating leg muscles does not put enough pressure on veins.
• Can cause Hemorrhoids