Ch 38: Peripheral Artery Disease of the Lower Extremities

Question 1

Involves thickening of artery walls, which results in a progressive narrowing of the arteries of the upper and lower extremities. Atherosclerosis is the leading cause in a majority of cases. Risk increases with age. Strongly r/t other types of CV disease. Marker of advanced systemic atherosclerosis. Largely undiagnosed until issues arise. Risk factors: tobacco use (nicotine is a vasoconstrictor and impairs transport and cellular use of O2 and increases blood viscosity and homocysteine levels), DM, hyperlipidemia, elevated CRP, uncontrolled HTN.

Answer 1

Peripheral artery disease

Question 2

Classic sx of PAD. Occur when the vessels are 60-75% occluded

Answer 2

Intermittent claudication: Ischemic muscle pain (from buildup of lactic acid from anaerobic metabolism) that is caused by a constant level of exercise. Resolves within 10 minutes or less with rest (lactic acid cleared and pain subsides). Reproducible. PAD of iliac arteries produces claudication in the buttocks and thighs. Calf claudication indicates femoral or popliteal artery involvement.

Question 3

Clinical manifestation of PAD. Numbness of tingling in the toes or feet. Gradual, reduced blood flow to neurons produces loss of pressure and deep pain sensations. Injuries often go unnoticed by pts. Severe shooting or burning pain in the extremity.

Answer 3

Paresthesia

Question 4

Clinical manifestations of PAD

Answer 4

Thin, shiny, and taut skin. Loss of hair on the lower legs. Diminished or absent pedal, popliteal, or femoral pulses. Pallor develops in response to leg elevation. Reactive hyperemia (redness of the foot) develops when the limb is in a dependent position (dependent rubor). Pain at rest (most often occurs in the foot or toes and is aggravated by limb elevation. Occurs when blood flow is insufficient to meet basic metabolic requirements of the distal tissues. Occurs more often at night because CO tends to drop during sleep and the limbs are at the level of the heart).

Question 5

Complications of PAD

Answer 5

Atrophy of the skin and underlying muscles d/t prolonged ischemia. Delayed healing with even minor trauma to the feet. Wound infection (gangrene, tissue necrosis). Arterial ulcers (may results in amputation if adequate blood flow is not restored; mostly over bony prominences on toes, feet, and lower legs).

Question 6

Dx of PAD

Answer 6

Doppler ultrasound with duplex imaging maps blood flow throughout the entire region of an artery; can determine the degree of blood flow. Segmental BPS are obtained (using Doppler and sphygmomanometer) at the thigh, below the knee, and at the ankle level while the pt is supine; a drop in segmental BP of greater than 30 mmHg suggests PAD. Angiography and magnetic resonance angiography delineate the location and extent of PAD.

Question 7

PAD screening tool. Performed using a hand-held Doppler. Calculated by dividing the ankle SBP by the higher of the left and right brachial SBPs. Normal is 0.91 to 1.30 and indicated adequate BP in the extremities. An ABI between 0.71 and 0.90 indicated mild PAD. Between 0.41 and 0.70 indicated moderate PAD.

Answer 7

Ankle-brachial index (ABI)

Question 8

Risk factor modification for PAD

Answer 8

Decrease the risk factors in all pts with PAD regardless of the severity of sx. Decrease stress, caffeine, nicotine. Control HTN. Aggressive tx of hyperlipidemia (dietary interventions and drug thearpy). BP maintained

Question 9

Ramipril (Altace). Decreases CV morbidity. Decreases mortality. Increases peripheral blood flow. Increases ABI. Increases walking distance.

Answer 9

ACE inhibitors

Question 10

Cilostazol (Pletal). Inhibits platelet aggregatio. Increases vasodilatio
Pentoxyifylline (Trental). Increases erythrocyte flexibility. Decreases blood viscosity.

Answer 10

Antiplatelet agents

Question 11

PAD nursing care

Answer 11

Exercise- walk until pain, rest, then walk further; 30-60 min/day, 3-5x/week.
LIMIT elevation of legs (stops blood flow)
Don’t cross legs. No restrictive clothing.
Can apply warmth, but not cold (don’t want to further vasoconstrict).
May be on low-dose ASA and/or Plavix

Question 12

Care of the leg with critical limb ischemia (a condition characterized by chronic ischemic rest pain lasting more than 2 weeks, arterial leg ulcers, or gangrene of the leg as a result of PAD).

Answer 12

Revascularization via bypass surgery. 
Protect from trauma. 
Decrease ischemic pain. 
Prevent/control infection. 
Improve arterial perfusion. 
Spinal cord stimulation to decrease pain. Angiogenesis to stimulate blood vessel growth.

Question 13

Indications: Intermittent claudication sx become incapacitating. Pain at rest. Ulceration or gangrene severe enough to threaten viability of the limb.

Answer 13

Interventional radiology procedures

Question 14

Involves the insertion of a catheter through the femoral artery. Catheter contains a cylindrical balloon. Balloon is inflated, dilating the vessel by compressing atherosclerotic intimal lining. Stent may be placed.

Answer 14

Percutaneous transluminal balloon angioplasty (PTA).

Question 15

Removal of the obstructing plaque. Performed using a cutting disc, laser, or rotating diamond tip.

Answer 15

Atherectomy

Question 16

Combines PTA and cold therapy. Liquid NO. Cold limits restenosis by reducing smooth muscle cell activity

Answer 16

Cryoplasty

Question 17

Surgical therapy for PAD

Answer 17

Most common approach is a peripheral artery bypass surgery with autogenous vein or synthetic graft to bypass blood around the lesion. PTA with stenting may also be used in combination with bypass surgery.

Question 18

The nurse teaches a pt with PAD. The nurse determines that further teaching is needed if the pt makes which statement?

a) I should not use heating pads to warm my feet
b) I should cut back on my walks if it causes pain in my legs
c) I will examine my feet every day for any sores or red areas
d) I can quit smoking if I use nicotine gym and a support group

Answer 18

b) I should cut back on my walks if it causes pain in my legs

Question 19

Permanent, localized outputting or dilation of the vessel wall. Occur in men more often than in women. Incidence increases with age. May occur in more than one location. Growth rate unpredictable (the larger it is, the greater the risk for rupture)

Answer 19

Aneurysm

Question 20

May involve the aortic arch and thoracic/and or abdominal aorta. Dilated aortic wall becomes lined with thrombi that can embolize (leads to acute ischemic sx in distal branches).

Answer 20

Aortic aneurysm

Question 21

causes of aortic aneurysm

Answer 21

Degenerative, congenital, mechanical (penetrating or blunt trauma). Inflammatory, infections. Most common: atherosclerosis

Question 22

Risk factors for aortic aneurysm

Answer 22

Age, male gender, high BP. CAD, familial Hx, high cholesterol, lower extremity PAD, carotid artery disease, previous stroke.
Smoking. Being overweight or obese.
White and Native Americans have a higher risk than African Americans, Hispanics, and American Asians.

Question 23

S/S of aneurysm.

Cx.

Answer 23

Depend on location. Oftentimes asymptomatic. Found on routine exam or when evaluated for another problem. May have a pulsating mass or bruit. Back or abdominal pain.
Cx: Rupture causing massive hemorrhage and hypovolemic shock. (severe back pain, Grey turner’s sign-flank bruising)

Question 24

An aneurysm in which the wall of the artery forms the aneurysm, with at least one vessel layer still intact. Can be fusiform (circumferential and relatively uniform in shape) or saccular (pouchlike with a narrow neck connecting the bulge to one side of the arterial wall)

Answer 24

True aneurysm

Question 25

Not an aneurysm but a disruption of all arterial wall layers with bleeding that is contained by surrounding anatomic structures. May results from trauma, infection, peripheral artery bypass graft surgery, or arterial leakage after removal of cannulae)

Answer 25

False aneurysm (pseudoaneurysm)

Question 26

Dx and Tx of aneurysm

Answer 26

Dx: CT is most accurate. X-ray (chest to reveal abnormal widening of the thoracic aorta). ECG to rule out MI. Ultrasound (monitor size). angiography
Tx: Control BP, modify risk factors, monitor size. Goal is to prevent rupture and extension. Be conservative if

Question 27

Nursing care with Repair

Answer 27

Thorough hx and physical exam.
Preop- bowel prep, mark pedal pulse sites.
Post-op: ICu for 1-2 days, may have chest tubes. Graft patency (good BP). CV (watch for dysrhythmias, increased O2 demands). Infection. GI (paralytic ileus is common, NG tube, watch for bowel infarction-loose, bloody stools). Neuro (LOC, pupils, facial symmetry, extremities. CMST-circulation, movement, sensation, temperature). Renal (hourly urine output, BUN, creatinine)

Question 28

Not a type of aneurysm Happens after intimal tear or with degradation of the aortic wall medial layer, worsens with high BP. Results from the creation of a false lumen b/w the intimal and the media of the arterial wall. If the blood-filled lumen ruptures through the outside aortic wall, it can be fatal. Classification is based on anatomic location and duration of onset. Chronic HTN.

Answer 28

Aortic dissection

Question 29

Risk factors and S/S for aortic dissection

Answer 29

RFs: age, aortitis (i.e. syphilis), trauma, HTN, connective tissue disorders (ie Marfan’s), cocaine use, atherosclerosis, males, pregnancy
S/S: Sudden, severe excruciating chest/back pain radiating to neck/shoulders. Neuro deficits (altered LOC, dizziness, syncope). If is progresses down the aorta, the abdominal organs and the lower extremities demonstrate evidence of decreased tissue perfusion. An ascending aortic dissection usu. produces some degree of disruption in blood flow in the coronary arteries and aortic valve insufficiency. The pt may develop angina; MI; and a new high-pitched heart murmur.

Question 30

Complications, diagnosis, treatment, nursing care of aortic dissection

Answer 30

Cx: cardiac tamponade (blood from dissection leaks into pericardial sac), ruptured aorta; ischemia to spinal cord, kidneys, abdomen
Dx: CT and transesophageal echocardiography are the standard for the dx of acute aortic dissection. CXR, MRI.
Tx: decrease BP with IV Esmolol, endovascular repair or may need surgical repair.
Nursing care: frequent, close monitoring of BP. Teach about recurrence.

Question 31

Sudden interruption in the arterial blood supply to a tissue, an organ, or an extremity that, if left untreated, can result in tissue death. It is caused by embolism, thrombosis or a preexisting atherosclerotic artery, or trauma. Thrombi become dislodged in and block an artery of the lower extremity in areas where vessels branch or there is atherosclerotic narrowing.
S/S: 6 P’s (pain, allow, paralysis-late sign, pulselessness, paresthesia, poikilothermic- coolness; take on temp of room)
Tx: call HCP; may do IV heparin infusion, may need removal of embolus/thrombus.

Answer 31

Acute Arterial Ischemic Problems

Question 32

Nonatherosclerotic, segmental, recurrent inflammatory/vaso-occlusive disorder of the small- and medium-sized arteries and veins of the upper and lower extremities. Mostly in young men with a long hx of tobacco and/or marijuana use and chronic periodontal infection, but w/o other CVD risk factors.
S/S: intermittent claudication, ischemic ulcerations, sensitivity to cold.
Dx of exclusion.
Tx: stop tobacco use, avoid trauma/cold to extremities, may need finger or toe amputation.

Answer 32

Thromboangiitis Obliterates (Buerger’s Disease)

Question 33

Episodic vasospastic disorder of small cutaneous arteries, most often involving the fingers and toes. Occurs primarily in young women. Abnormalities in the vascular, intravascular, and neuronal mechanisms that cause an imbalance between vasodilation and vasoconstriction.
S/S: digits become white, then blue, then red; throbbing pain, tingling, swelling; attack c/b cold, stress, tobacco, caffeine
Tx: try to prevent episodes, put hands in warm water to decrease vasospasm, can try calcium channel blockers

Answer 33

Raynaud’s Phenomenon

Question 34

Primary cause of venous thromboembolism. Venous stasis (obesity, pregnancy, Afib, long trips, prolonged surgeries, immobility)
Damage of the endothelium (chemo, diabetes, sepsis, trauma, atherosclerosis)
Hyper coagulability of the blood (blood disorders, corticosteroids, estrogens, tobacco usage)

Answer 34

Virchow’s triad

Question 35

Usually caused by vein trauma from IV cannulation, varicose veins. Palpable, firm, subcutaneous cordlike vein. Area surrounding the vein may be itchy, painful to the touch, reddened and warm. Risk factors include age, pregnancy, obesity, estrogen therapy.
Tx: immediate removal of IV cateter, elevate extremity, warm/moist heat, oral NSAIDs, no systemic anticoagulants

Answer 35

Superficial vein thrombosis

Question 36

S/S: unilateral edema, pain, paresthesia, warm, red, temp >100.4, tenderness.
Cx: PE, chronic venous insufficiency, phlegmasia cerulea dozens (rare; swollen, blue, painful leg).
Tx: Prevention with early walking; change positions q2hrs; compression stockings, SCDs; may need preventation anticoagulation. If confirmed, no SCDs, IV heparin and oral warfarin for at least 5 days; may need thrombolytics or surgery

Answer 36

Deep vein thrombosis

Question 37

DVT drug therapy

Answer 37

Goal is to prevent clot formation or further clot development and embolization. Anticoagulants do not dissolve clots (the body will lyse the clot over time). Vitamin K antagonists (warfarin). Indirect thrombin inhibitors (heparins). Direct thrombin inhibitors (synthetics). Factor Xa inhibitors (no for use with renal problems or artificial valve). ASA alone is not recommended

Question 38

Warfarin- oral only. Used for long-term anticoagulation. Takes 3-4 days to start working so need to overlap with heparin for 5 days. Monitor levels with INR (keep at 2-3). Don’t give with ASA, NSAIDs, Dilantin, many vitamins/supplements. Levels affected by green, leafy veggie intake (drug will be less effective. Adjust coumadin dose based on normal intake). Vitamin K is the antidote.

Answer 38

Vitamin K antagonists

Question 39

SC (prevention) or IV (VTE tx). LMWH is SC. Closely monitor aPTT levels.
Cx: bleeding, HIT (must stop).
UH (unfractionated) and LMWH (much fewer cx and does not typically require monitoring and dose adjustment).
Protamine sulfate is the antidote

Answer 39

Heparin.
Thrombin inhibitor.
HIT= heparin induced thrombocytopenia

Question 40

Hirudin derivatives or synthetic, IV or SC. Refludan, Angiomax, Acova, Arixtra.
Binds with thrombin and inhibits its function. Can be used for pts with HIT. Monitor with aPTT or activated clotting time. No antidote.

Answer 40

Direct thrombin inhibitors

Question 41

dabigatran (Pradaxa); rivaroxaban (Xarelto); apixaban (Eliquis); edoxaban (Lixiana).
No antidote. Clinically equivalent to warfarin. Costly. For use in Afib to prevent stroke or after DVT occurrence, NOT with valvular disease.

Answer 41

Novel Oral Anticoagulants

Question 42

Surgical management of DVT

Answer 42

Thrombectomy- not used unless it is a huge occlusion

Inferior vena vaca filter- for recurrent DVT or PE prevention

Question 43

DVT nursing care

Answer 43

Bed rest with limb elevation for acute DVT. No massage or SCDs for acute DVT. Assess for PE. Teach about prevention and risk factors (no smoking; no oral BCPs; prevent dehydration; no pillows behind the knees, no crossing the legs; ambulate, ROM, get moving; compression stockings, SCDs).

Question 44

Congenital vein weakness, previous VTE. Can also occur in esophagus, spermatic cords, anorectal areas. A lot of risk factors.
S/S: heavy, achy feeling after prolonged standing, swelling, leg cramps, looks ugly.
Cx: SVT, rupture of vein (rare).
Tx: not for cosmetic reasons; sclerotherapy, laser therapy, vein ligation/removal

Answer 44

Varicose veins

Question 45

Develops when veins and valves fail to keep blood moving forward. Can lead to venous leg ulcers. Not life-threatening but painful, debilitation, and costly. Common in the elderly. S/S: leathery, brown skin; prolonged edema; stasis dermatitis; itching; painful ulcers; no claudication.
Cx: cellulitis, slow wound healing
Tx: compression therapy (if no PAD); moist dressings; good diet, weightless, tight blood glucose control; no ABX unless sign of infection.
Care: TED hose day and evening; legs elevated 4-5 x/day

Answer 45

Chronic venous insufficiency and leg ulcers

Question 46

Pain: sharp, intermittent claudication. Relieved by rest
Pulses: decreased, absent
Edema: none
Skin: cool, shiny, scaly, hairless, pale when elevated and red when dependent
Tx: do NOT elevate, do NOT compress (need to improve blood flow to the leg)

Answer 46

Arterial disease

Question 47

Pain: aching, deep, heaviness, fatigue. Relieved by activity or elevation
Pulses: present
Edema: present
Skim- warm, thickened, tough, dark/bronze, rubber, stasis ulcers
Tx: elevate, TED hose (compression), need to increase venous return

Answer 47

Venous disease

Question 48

Following an aortic aneurysm repair, the pt suddenly develops severe pain in the right lower extremity. The right pedal pulse is decreased and the right foot is cool and pale. Which cx should the nurse expect?

a) Hypothermia
b) A wound infection
c) Bleeding from the graft site
d) An embolization or graft occlusion

Answer 48

d) An embolization or graft occlusion