PVD

Question 1

What is PVD?

Answer 1

Compromised blood flow to the extremities

Question 2

What causes PVD?

Answer 2

1) Atherosclerosis** (chronic problem)
2) Arterial embolism (acute problem)
- Emboli may originate from heart, abdominal aorta, or femoral artery
3) Vasculitis
- Inflammation of the walls of the BVs

Question 3

Common arteries for athersclerotic plaques

Answer 3

Distal abdominal aorta
Iliac arteries
Subclavian arteries
Coronaries

Question 4

If your patient has PVD, what should you also assume?

Answer 4

They have CAD.

Question 5

Over __% of people over 75 have atherosclerosis

Answer 5

Over 70%

Thus for everyone over 75, assume they have PVD, and thusly also assume that they have CAD

Question 6

Risk factors for atherosclerosis

Answer 6

DM
Essential HTN
Hyperlipidemia
Smoking
Aging
Men
Obesity and physical inactivity
Sedentary lifestyle
Family hx of premature atherosclerosis
Hyperhomocysteinemia (high levels of homocystein predispose people to endothelial damage)

Question 7

What is intermittent claudication?

Answer 7

Angina of the legs!
Pain and limping when walking or exercising. Pain is experienced in the calf, thigh, or buttock, and is relieved with rest.

Question 8

S/S of PVD

Answer 8

Intermittent claudication**
Feet are cold to the touch
Pain in legs when lying flat, and relieved by a sitting position
Weak or absent pulses in legs/feet
Pallor when legs are raised
Dependent rubor (redness in legs when in a dependent position)
- Shiny skin
- Loss of hair
- Thickened toenails (may have fungal infection)

Question 9

What is the most severe symptom of PVD?

Answer 9

Critical limb ischemia (CLI)

Question 10

What is critical limb ischemia (CLI)?

Answer 10

Extreme form of intermittent claudication

• Pain in legs at rest
• Blood flow is so diminished that even basic metabolic demands are not met
• Associated with non-healing ulcers and gangrene

Question 11

Diagnostic tests for PVD/atherosclerosis

Answer 11

Doppler U/S
Ankle/Brachial Index
Duplex Ultrasonographic Scan
Transcutaneous Oximetry
- Test to measure oxygen content in the tissues
- Normal is 60mmHg
- < 40mmHg = skin ischemia
MRI
Angio with contrast

Question 12

What is the ankle/brachial index?

Answer 12

Ratio of the BP in the lower legs to BP in the arms
Normal is .95
< .9 = claudication
< .4 = Pain at rest (CLI)
< .25 = ischemic ulceration or impending gangrene

Question 13

Goals of treating PVD

Answer 13

Improve functional status
Prevent stroke
Prevent limb loss
Reduce potential atherosclerotic progression and cardiovascular morbidity

Question 14

How to treat PVD

Answer 14

Treat risk factors the patient has (lifestyle changes)
Lipid-loweing therapy (statins)
Vitamin C and E supplements
Anti-plt therapy
Revascularization procedures
Amputation

Question 15

Revascularization procedures we may see our patients for

Answer 15

• Percutaneous transluminal angioplasty (PTA) with possible stent placement
• Bypass surgeries
• Intra-arterial thrombolytic therapies
• Balloon-catheter embolectomy
• Endarterectomy

Question 16

Indications for revascularization procedures

Answer 16

1) Acute ischemia
- Emboli
- Thrombi
- Pseudoaneurysm from previous fem a-line
- Ischemia within 4-6 hours post-op

2) Chronic Ischemia
- Atherosclerosis that causes claudication

Question 17

Patients presenting for revascularization procedures were probably given ____ overnight

Answer 17

Heparin
Surgeons don’t want the vessels to clot
Studies show that regional blockade if best for these patients (be aware of coagulopathy)

Question 18

Description of peripheral revascularization surgery

Answer 18

1) Donor and recipient arteries are exposed, tunnel is created and graft is passed
2) Graft may be saphenous vein or prosthesis
3) Heparin and papaverdin are given IV
4) Do NOT give phenylephrine in these cases, as it will directly oppose the actions of papaverdin
5) Anastomoses are constructed
6) Arteriogram and doppler to assess flow and quality of pulses
7) Heparin probably won’t be reversed to prevent clotting of the new graft

Question 19

Anesthetic considerations for the person with PVD

Answer 19

1) Always assume they have CAD!! Pt with PVD has a 3-5x greater risk of MI, stroke, and death.
- No long periods of hyper or hypotension or tachycardia!!

2) CABG operations are usually performed before surgery on the peripehral vasculature in pts who experience angina and claudication

Question 20

You should always assume that someone with PVD has ____ unless _____

Answer 20

CAD

Unless they had a CABG

Question 21

Risks of revascularization surgeries

Answer 21

Hemorrhage and infection (like every surgery ever)
PE (clot may become dislodged)
Cardiac complications (from assumed CAD)
- MI, low CO, pulmonary edema
Ischemia of the lower extremities if lithotomy position is used

Question 22

Monitoring for peripheral re-vascularization

Answer 22

5-Lead EKG
A-line
Ability to monitor intravascular volume with CVP, CO, or foley

Question 23

Benefits of RA vs. GA for revascularization (vascular grafting)

Answer 23

1) Increased graft blood flow
- lower incidence of graft occlusion
2) Less increase in SVR with cross-clamping
3) Better post-op pain relief
4) Less activation of the coagulation system
5) No difference in cardiopulmonary complications between RA and GA
6) Sympathectomy makes it easier for the surgeons

Even with RA, we do a balanced technique with propofol (sedation)

Question 24

Method of RA preferred for peripheral revascularization

Answer 24

Spinal

Remember that the patient will be heparinized, so they’re at higher risk for epidural bleed if we place it here

Question 25

If your patient has coagulopathy, should you do RA or GA?

Answer 25

GA, bitch.

Question 26

Make sure to make note of the time that this happens during a revascularization case

Answer 26

Time heparin is given.

Heparin peaks in 3-5 minutes, and this is when they’ll start doing shit.