PVD reduced Flashcards

1
Q

What is PVD

A
  1. Compromised blood flow to the extremities
  2. Ankle-brachial index of less than 0.9
    • Ratio of SBP in ankle vs SBP in brachial artery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What causes PVD

A
  1. Atherosclerosis- most common cause
    • goes hand in hand with CAD
  2. Arterial embolism- acute cause
  3. Vasculitis - inflam of vasculature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Is someone has PVD, it can be assumed that they likely have ___

Over what age can it be assumed that someone has PVD

A

CAD

Over 75 y.o. (exceeds 70%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Atherosclerosis risk factors

A
  1. DM
  2. Obesity/Inactivity
  3. Advanced age
  4. Male gender
  5. Family Hx of early atherosclerosis
  6. HTN
  7. HLD
  8. Smoking
  9. Hyper-homo-cystein-emia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Atherosclerosis s/s

A
  1. Intermittent claudication → most common symptom
    • pain that starts with walking/exercise and <strong>stops with rest</strong>
  2. cool/cold feet or leg pain while lying flat
    • relieved by sitting
    • sign of advanced disease
  3. loss of pulses in feet/legs
  4. pale color in legs when raised
    • <strong>dependent</strong> <strong>rubor</strong> - redness in dependent position
  5. shiny skin
  6. loss of hair on feet
  7. thinckened toenails→may have fungal infection
  8. critical limb ischemia
    • Most severe symptom
    • “rest pain”
    • lack of O2 to the limb at rest
    • associated with non-healing ulcers & gangrene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Diagnostic tests for atherosclerosis

A
  1. Duplex and Doppler Ultrasonography
    • measures lamilar flow it is either red = towards probe, blue = away
  2. Ankle/Brachial Index
    • Normal index is 0.95 at rest
    • < 0.9 = claudication
    • < 0.4 = pain with resting
    • < 0.25 = ischemic ulceration or impending gangrene
  3. Transcutaneous oximetry
    • 60 mm/Hg = Normal
    • < 40 mmHg in patients with limb ischemia
  4. MRI
  5. Contrast angiography - locates blocked area
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

atherosclerosis treatment

A
  1. LIfestyle modification
    • exercise, weight loss, smoking cessation
  2. Lipid-lowering medications
    • statin drugs
  3. Vitamin C, E, folate
  4. Antiplatelet therapy
  5. Revascularization
    • PTA w/stent, Bypass, Intra-arterial thrombolytic therapy, balloon embolectomy, endarterectomy
  6. Amputation :-(
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Surgical approach to Peripheral Revascularization

A
  • Donor and Recipient arteries are exposed and a tunnel is created for a bipass graft
  • Graft either Saphenous vein or prosthesis
  • Heparin given IV
    • must note the time (3-5 min onset)
    • Still able to use regional anesthesia (dose 3000-5000)
  • Anastamosis is made
  • Arteriogram to confirm flow
  • Heparin is usually NOT reversed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Giving what drug during revascularization will likely get you sent home for the day

A

Phenylephrine

Don’t get sent home for the day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

PVD

Anesthetitc risks and considerations

A
  1. Principal risk - athlerrosclerosis and ischemic heart disease (manage like they have CAD)
    • AVOID hypo/hypertension
    • AVOID tachycardia
  2. Patients with PVD have 3-5x greater risk of stroke, MI and death
  3. To reduce risks of revascularization suregery:
    • Patents who experience angina and claudication will get a CABG prior to revascularization surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Risks with revascularization

A
  • Pulmonary embolism (watch ETCO2)
  • MI
  • Low CO→ischemia
  • Hemorrhage
  • Infection
  • Pulmonary edema
  • Risks associated with the lithotomy position -
    • nerve palsy, limb ischemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

peripheral revascularization

Pre-op meds and Monitoring

A
  • Preop → make sure pt takes beta-blockers and/or other chronic medication
  • Intra-op monitoringConsider co-morbidities (<strong>CAD</strong>, <strong>diabetes</strong>, <strong>HTN)</strong>
    1. Fluid and volume status
      • A-line + CVP or foley to monitor fluid volume status/end organ profusion
      • Estimate blood loss and 3rd space fluid loss
      • Pulse ox oxygenation
    2. Follow Blood Gasses + coags + electrolytes
    3. Note Cross-clamp time (limb ischemia time)
    4. Note when heparin is given(peaks in <strong>3-5</strong>min)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

peripheral revascularization

Anesthetic management

A

​Regional is preferred (spinal > epidural = less hematoma risk)

  • Increased graft blood flow (grafts do better)
    • spinal is preferred - less hematoma risk
  • Less increase in SVR with cross-clamping (sympatectomy)
  • Better Postop pain relief (​less SNS outflow and less vasoconstriction)
  • Less activation of the coagulation system
    • less risk of grafts clotting and having to return to the OR
    • decreased SNS outflow = less inflammation
  • ​Make sure to check INR and platelets prior to regional
  • There is NO difference if CV complications with regional vs GA
    • ​BUT there is a SIGNIFICANT difference in complication rate of GRAFT OCCLUSIONS
    • General hage an increased risk of occlusions!!!
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In revascularization which is prefered, spinal or epidural?

A

Spinal

higher risk of hematoma with epidural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What advantage has been shown with regional vs general in revascularization

A

Regional has improved outcomes for graft occlusion, and post op pain management

…but shows no benefit in terms of cardiopulmonary complications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

PVD

Regional vs. General?

A
  • Assess for coagulopathy
  • General is indicated for pts in which heparin therapy has already been started
  • Regional is a good consideration b/c:
    • has <strong>lower</strong> incidence of post-op graft occlusion, r/t <strong>↓SNS outflow</strong>
      • vasodilation, ↓circulating catecholamines, and ↓ blood viscosity r/t fluid volume loading
    • If considering regional, <strong>spinal</strong> may be better choice over epidural to avoid <strong>hematoma</strong> (much smaller needle)
    • Studies have shown <strong>no difference</strong> btw RA & GA in terms of cardiopulmonary complications
  • Monitoring
    • pt’s present w/other co-morbidities (CAD,DM,HTN)-degree of monitoring depends on sx & extent of dz
    • Consider use of <strong>a-line</strong>
      • good documentation that an assessment of collateral flow has been performed esp w/co-existing microvascular disease such as Reynaud’s
    • <strong>consider need to monitor intravascular volume</strong>
      • <strong>CVP</strong>, <strong>Swan</strong>, or simply via <strong>foley</strong> - the “<strong>poor man’s Swan</strong>”
    • Initial revascularization procedures generally have minimal blood loss & minimal third space loss
  • Pre-op
    • make sure pt’s take <strong>beta</strong> <strong>blockers</strong> or other chronic meds such as antihypertensives (except ACE-inhibs)
  • Post-op
    • provide adequate analgesia to <strong>prevent ↑SNS stim</strong> & therefore maintain graft patency
    • can use <strong>Precidex</strong> (dexmedetomidine) an alpha-2 agonist to <strong>attenuate ↑HR & NE r</strong>elease during emergence or extubation (less sedating than propofol but can cause marked hypotension & bradycardia) Dose = 0.2-0.7 mcg/kg IV