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Peripheral Vascular Disease gangrene

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					PERIPHERAL VASCULAR
       DISEASE


Presented by Jill Kerkman
Pathophysiology

 Form of atherosclerosis
 Progressive disease
   May occur suddenly if an embolism occurs
    or when a blood clot rapidly develops in a
    blood vessel restricted by an
    atherosclerotic plaque, and the blood flow
    is quickly cut off.
 PVD is a generic term that encompasses
  vascular insufficiencies such as
  arteriosclerosis, arterial stenosis, Raynaud’s
  phenomenon.
 Peripheral arteriosclerosis is common in the
  elderly and is often associated with
  hypertension and hyperlipidemia.
   PVD is frequently observed in patients with
     CAD, diabetes, and a long-term history of
     smoking.
Two types of PVD
 Functional
   Doesn’t have an organic cause.
   Doesn’t involve defects in blood vessels’
    structure, usually short-term effects and
    come and go.
   Ex: Raynaud’s disease.
 Organic
   Caused by structural changes in the blood
    vessels, such as inflammation.
   Ex: Peripheral artery disease, caused by
    fatty buildups in arteries.
How Common is PVD?

 Affects about 1 in 20 people over the age of
  50, or 8 million people in the US.
 PVD is only diagnosed in 50% of the
  population.
 Symptomatic PVD carries at least a 30% risk
  of death within 5 years and almost 50% within
  10 years, primarily due to MI (60%) or stroke
  (12%).
Symptoms of PVD
 Leg or hip pain during walking (intermittent
  claudication).
 The pain stops when you rest.
 Numbness, tingling or weakness in the legs.
 Burning or aching pain in feet or toes when
  resting.
 Sore on leg or foot that won’t heal.
 Cold legs or feet.
 Color change in skin of legs or feet.
 Loss of hair on legs.
The 5 P’s

 Peripheral signs of PVD are the classic 5 P’s
  Pulselessness
  Paralysis
  Paraesthesia
  Pain
  Pallor
 Paralysis and paraesthesia suggest limb-
  threatening ischemia and mandate prompt
  evaluation and consultation.
 Advanced PVD may manifest as mottling in a
  “fishnet pattern”, pulselessness, numbness,
  or cyanosis. Paralysis may follow, and the
  extremity may become cold; gangrene
  eventaully may be seen. Poorly healing
  injuries or ulcers in the extremities help
  provide evidence of preexisting PVD.
  Who is at risk for PVD?
 Over the age of 50
 Smokers
 Diabetics
 Overweight (especially with syndrome X or
  hyperinsulinism)
 Male sex
 Sedentary people
 People who have hypertension or high
  cholesterol
 Family history of heart or vascular disease
 Pain Scale
 A subjective grading scale for PVD pain is as
  follows:
   Grade 1: Definite discomfort or pain, but only
     of initial or modest levels (established, but
     minimal).
   Grade 2: Moderate discomfort or pain from
     which the patient’s attention can be diverted,
     for example by conversation.
   Grade 3: Intense pain (short of Grade 4) from
     which the patient’s attention cannot be
     diverted.
   Grade 4: Excruciating and unbearable pain.
How is PVD Diagnosed?
 Ankle-Brachial Index Test (ABI)
  The blood pressure in your arms and
    ankles is checked using a regular blood
    pressure cuff and a special ultrasound
    stethoscope called a Doppler.
  The pressure in your ankle is compared to
    the pressure in your arm to determine how
    well your blood is flowing.
  The index is determined by dividing ankle
    systolic BP by arm systolic BP.
 ABI
 Measurements are usually taken at rest and
  after standardized treadmill exercise (i.e.. For 5
  min. at 2mph, 12%).
 A normal resting ABI is 1 or 1.1.
 An index of 0.9 or less indicates the presence
  of obstructive disease.
 0.5 or less suggests multiple-level arterial
  disease.
 An ABI of less than 0.26 indicates severe, limb-
  threatening arterial compromise.
Duplex Ultrasonography and
Doppler Color-Flow Imaging
 Technical advances in ultrasonography have
  allowed reproducible measurements of blood
  vessels and blood flow as well as
  standardization of criteria for assessment of
  PVD.
 Doppler color-flow imaging are useful in
  localizing diseased segments, and spectral
  imaging can assess lesion severity.
Magnetic Resonance Imaging
and Angiography
 Useful in evaluating arterial dissection and
  characterizing vessel-wall morphology
  (including hematoma or thrombus).

 Computed Tomography (CT) Angiography
  Treatment for PVD
 Severe lower extremity PVD is treated initially
  with cardiovascular disease risk factor
  modification:
  Exercise training
  Medication
  Diet
  Stop Smoking
  Interventional Radiology
  Surgery
  Gene-Based Therapy
Exercise

 Research has shown that regular exercise is
  the most consistently effective treatment for
  PVD.
 Patients who have taken part in a regular
  exercise program for at least 3 months have
  seen substantial increases in the distances
  they are able to walk without experiencing
  painful symptoms.
Exercise Prescription
 Training Intensity
   Initial
     • Set by result of peak treadmill.
     • Starting exercise work load brings on
       claudication pain.
   Subsequent
     • Speed or grade increased if patient
       walks > 10 minutes.
     • Grade increased first if speed > 2 mph.
     • Speed increased first if < 2 mph.
Exercise Prescription

 Duration
  Initial
     • 35 minutes (intermittent walking)
  Subsequent
     • Add 5 minutes every session until 50
       minutes (intermittent walking) is possible
Exercise Prescription

 Frequency
   3-5 times per week.

 Specificity of Activity
  Treadmill walking is the recommended
    exercise.
Stop Smoking

 On average, smokers are diagnosed with
  PVD as much as 10 years earlier than non-
  smokers.
 Stopping smoking now is the single most
  important thing you can do to halt the
  progression of PVD or prevent it in the future.
Medications
 Drugs that lower cholesterol or control high
  blood pressure.
 Decrease blood viscosity.
   Trental, Persantine, or Coumadin
 Antiplatlet agents: their primary long-term
  benefit is reduction in cardiovascular events
  and mortality.
   ASA doses of 75 to 325mg QD have
     shown protective benefits.
   Ticlid and Plavix also have shown promise
     in disease prevention and in therapy after
     vascular intervention.
Interventional Radiology
Treatments
 Angioplasty
 Stents
 Thrombolytic Therapy
 Stent-Grafts
 Gene-Based Therapy
 The field of molecular genetics has provided
  new understanding of vascular physiology and
  pathology and has opened exciting frontiers in
  the treatment of PVD.
 Direct gene transfer by intramuscular injection
  of DNA encoded with vascular growth factors
  has resulted in growth of new vessels and
  collateral circulation in chronically occluded
  lower extremity arterial vessels.
Surgical Treatments for PVD

 Thrombectomy
 Bypass Grafts
 Aneurysms
 Most common lethal peripheral vascular
  abnormality.
   An artery whose diameter is 1.5 times the
     normal.
 Aortic aneurysms are caused by weakening of
  the artery walls due to atherosclerosis. The
  weakened walls balloon out, forming an
  aneurysm.
 When blood pumps from the heart through the
  aorta, it places pressure on the aneurysm
  walls. Over time, the aneurysm can get bigger
  and bigger, until eventually it may rupture.
Aortoiliac Occlusive Disease
 Typically involves the distal abdominal aorta
  as well as the common and external iliac
  arteries.
 Aortobifemoral bypass with a prosthetic graft
  has been the traditional treatment of choice
  for aortoiliac occlusive disease since the
  1960’s.
 The operative morbidity and mortality are in
  the 2% range, and long-term patency
  exceeds 90%.
Superficial Femoral Occlusive
Disease
 Presents with symptoms of claudication of the
  calf and sole of the foot.
   Usually improves as collateral circulation
     develops.
 Best treatment initially is antiplatelet therapy
  in combination with a vigorous exercise
  program.
Tibial Artery Disease

 Distal atherosclerotic disease involving the
  tibioperoneal trunk and the tibial vessels is
  the most difficult to treat and leads to the
  greatest morbidity and tissue loss.
 ABI is typically less than 0.4 before rest pain
  develops, and any value less than 0.3 almost
  always results in ischemic tissue loss.
Upper Extremity Disease

 Atherosclerotic disease involving the arms is
  almost always limited to the larger proximal
  vessels and rarely involves the brachial,
  radial, or ulnar arteries.
 Although these patients have no symptoms,
  they can have a large discrepancy in BP
  between the left and right arms.
   Always prudent to measure BP in both
     arms.
Thrombosis
 A thrombus, or blood clot, within a blood
  vessel.
 Normally, a blood clot forms to prevent
  bleeding but a thrombus is an abnormal blood
  clot in the vessel when it is not even
  punctured.
 The clotting process may be encouraged by
  the buildup of fatty acids on the vessel walls.
 Thrombosis in the vein may cause pain and
  swelling.
Deep Venous Thrombosis
 A blood clot in a deep vein.
 May form on the valves within the vein, and
  may subsequently increase in size to totally
  occlude the vein.
 Sometimes parts of the clot may break off
  and travel in the bloodstream to the lungs and
  cause serious health problems (pulmonary
  embolism).
 DVT is perhaps the most dangerous problem.
 Patients with DVT have a 30 to 40% risk of
  recurrence later in life.
Phlebitis
 Inflammation of the leg veins.
 Two types:
   Inflammation of the veins on the surface of
     the leg (more common).
   Inflammation of the deep veins of the leg.
 Phlebitis is caused by an infection or injury.
 Can cause a blood clot to form and this clot
  can then embolize and result in pulmonary
  embolism. This is the worst thing that can
  happen if you have phlebitis.
Pulmonary Embolism
 An embolus is a clot or any other piece of
  material that is carried around in the blood.
 Pulmonary embolism is where the embolus
  gets stuck in a vessel going to the lungs.
 The only way a clot can go to a vessel in the
  lungs is if it passes through the heart and is
  pumped out of the pulmonary artery.
 So, the closer the clot is to the heart, the
  more likely to get a pulmonary embolism.
  Varicose Veins
 Caused because either the blood flow is too slow
  making the vein pile up with blood or the valve in
  the vein is not working well so the blood falls
  down due to gravity and piles up in the veins of
  the legs.
 Sclerotherapy: Irritant chemical is injected into
  the veins, causing them to scar and seal off. This
  “detours” the blood to nearby healthier veins.
 Stripping: Procedure used to remove larger
  varicose veins. Parts of the vein can be removed
  or tied off, or the entire vein can be removed.
 Surgery continues to play an important role in
  the management of peripheral vascular
  disease.
 Revascularization procedures provide
  excellent outcomes for many patients at risk
  for loss of a limb or seriously impaired quality
  of life.
 Although endovascular techniques are now
  being used for managing many vascular
  problems, the traditional surgical approaches
  still offer well-documented benefits.