PVD Flashcards
2 types of PVD
- Arterial (PAD)
- Venous (PVD)
- Physiologically both present as insufficient tissue perfusion
PAD: Facts (Bloods)
- atherosclerosis can affect any arteries in the body
- in the neck or brain = risk for stroke
- In the arteries of the legs = pain, tissue damage, and gangrene
- most commonly: claudication
PVD: Facts (Crips)
- Phlebitis
- DVT
- PE
- Chronic venous insufficiency
- Varicose veins
PAD: Guidelines
- Emphasizes use of ankle-brachial index (ABI) measurements for earlier diagnosis
- Increased attention on smoking cessation
- Better use of antiplatelet and other antithrombotic medications
PAD: Causes
- Atheroscleriosis (plaques of cholesterol forms on arterial wall) vs. arteriosclerosis (hardening of arteries)
- Lower extremity PAD may be atherosclerotic, thromboembolic, inflammatory, or traumatic
- Common Causes: *Atherosclerosis, blood clots, trauma, spasms, congenital structural defects, and venous incompetence 2/t valve obstruction
PAD: Risk factors
- Smoking
- Age
- Gender
- HTN
- HLD
- DM
- Hyperhomocysteinemia
PAD in lower extremities
- Asymptomatic LE PAD
- Intermittent claudication
- Chronic ischemic limb pain
- Acute ischemic limb pain
- Lower extremity limb pain
Leg Pain: Causes
- Problems with blocked blood vessels and poor circulation
- Problems with bones and joints: Arthritis of knees, ankles, and hips
- Nerve problems: Sciatica, diabetic neuropathy
Focus on PAD
- 50% of pt’s with PAD are asymptomatic
- The most common symptoms are intermittent claudication and rest pain
- Intermittent claudication is pain or cramping in arms or legs that occurs with exercise and subsides with rest
- Severity and location of the pain depends on location and extent of blockage of involved artery
- Most common location is calves
Atherosclerosis: Target organs
- Carotid-> Brain-> TIA/stroke
- Aortic/Iliac-> Legs-> Intermittent claudication/impotence
- Renal-> Kidneys-> HTN/ESRD
- Mesenteric-> Intestines-> Ischemic bowel
- Femoral, popliteal, tibial-> Legs-> Intermittent claudication, rest pain, amputation
Rest Pain
- Occurs when artery occlusion is so critical there is an O2 deficit in lower extremities at rest
- Typically affects feet, is usually severe, and occurs at night when patient is supine
- This is critical limb ischemia (CLI)
PAD: Other symptoms
- Numbness of extremities
- Weakness and atrophy of calf muscle
- A feeling of coldness in the legs or feet
- Changes in color of feet: Pallor when elevated/rubor in dependent position
- Hair loss over dorsum of feet
- Thickening of toenails
- Painful ulcers and/or gangrene in tissue with CLI; typically in toes
Claudication
- Symptoms of leg fatigue and cramps that patients with PAD describe when they exert the muscles of the legs
- Severity of ichemia can be classified according to either the Fontaine or Rutherford categories
- Iliac arteries -> pain high in thigh and buttocks while walking
- Femoral/popliteal arteries -> pain in calves
- Tibial -> pain in feet
- Leriche syndrome: intermittent claudication and impotence with clinical significant decreased or absent femoral pulses = narrowing of aorta
Goals for Treatment of PAD
- Limb outcomes: Improved ability to walk, increase in peak walking distance, improvement of QoL, prevent progression to CLI and amputation
- Cardiovascular morbidity and mortality outcomes: Decrease in morbidity from non-fatal MI and CVA; Decreases in cardiovascular mortality from fatal MI and CVA
Management of PAD: Cardiovascular risk reduction
- Antihypertensives
- Diabetes therapy
- Statins
- Homocysteine lowering therapy
- Lifestyle modifications
Management of PAD: Pharmacologic treatment
- Cilostazol (Pletal)
- Pentoxifylline (Trental)
- ASA
- Clopidogrel (Plavix)
PAD: Exercise
- 3-5x/week
- 35-50min
- Treadmill or track walking to near-maximal claudication pain
- > =6 months
- 100-150% improvement in maximal walking distance and associated improvement in QoL
Lipid goals for PAD
- Treatment with statin for LDL <70
Inflammation and Omega-3s
AHA Recommendations
- Eat fish 2x/wk
- Forms: fish, tofu, soybeans, walnut, flaxseed
Antiplatelet therapy: PAD
- ASA: 75-325mg/day (early)
- Plavix 75mg/day (severe)
Vitamins to decrease homocysteine levels
B complex:
- Folic acid
- Cobalamin (B12)
- Pyridoxine (B6)
Pharmacotherapy for claudication
- Cilostazol (Pletal) 100mg PO BID (start at 50mg BID)
- Platelet aggregation inhibitor; vasodilator; increases HDL; lowers TG; inhibits smooth muscle proliferation
- Pentoxifylline (Trental): 400mg TID
- Mild vasodilation; weak antiplatelet activity
Cilostazol (Pletal): Black box warning
- CI in HF of any severity
- Causes decreased survival in patients with class III & IV HF
PAD: Lifestyle modifications
- low-fat diet
- regular exercise
- tobacco cessation
- foot care
PAD: When to refer
- Lower extremity pain with rest
- severe claudication
- prolonged pain
- sudden color change or numbness in extremity
- s/s of gangrene
Critical limb ischemia (CLI)
- limb pain that occurs at rest or impending limb loss that is caused by severe compromise of blood flow to the affected extremity
- CLI should be used for all patients with all patients with chronic ischemic rest pain, ulcers, or gangrene attributable to proven PAD
Treatment of CLI
- Objective: increase blood flow to the affected extremity to relive pain, heal ischemic ulcerations, and avoid limb loss
- Medical Mgmt.: antiplatelet agents, anticoagulants, maintenance of limb in dependent position
- Treatment of infection
- Use of non-weight bearing orthotics
- Chronic CLI is associated with 1yr mortality >20%
Acute Limb Ischemia
- Rapid or sudden decrease in limb perfusion threatens tissue viability
- “Blue toe syndrome”: shower of atherosclerotic plaque occludes previously healthy microarterial vessels in feet and toes
- Aneurysm: typically popliteal artery; less commonly in femoral artery
- 5 P’s: pain, pallor, paresthesia, pulselessness, paralysis + polar (cold extremity)
Acute Limb Ischemia: Treatment
- Hospitalization
- Heparin
Upper extermity PAD
- Same mgmt.
- Raynaud’s phenomenon: Unsure of cause; may or may not have vascular origin
Occlusion of the peripheral veins
- Varicose veins
- Venous stasis/Chronic venous insufficiency
- DVT
- Stasis dermatitis
- Ulceration of lower extremities
Varicose Veins
- Engorged superficial veins in the lower extremities
- Treatment:
- Exercise
- Elevation of legs
- Compression stockings
- Sclerotherapy
- Ablation
- Laser therapy
- Vein stripping
Preventing varicose veins
- Cross legs at ankles instead of knees when sitting
- Avoid high heels, which limit the use of calf muscles
- Avoid restrictive clothing which limit blood flow in groin and calf
- Avoid prolonged sitting or standing
- Take breaks to elevate legs or walk around to help move blood along and prevent valve failure
Chronic venous insufficiency
- Same causes as varicose veins
- S/S: Swelling ankles; tightness in calves; legs feel heavy, tired, restless orachy
- Sometimes feel pain while walking or shortly after stopping
- Early treatment same as varicose veins
- Later: Surgical bypass and repair
Thrombophlebitis
- Superficial Tx: Rest, pain relief, antibiotic, warm compresses, compression stockings
- Deep vein thrombophlebitis: tx is anticoagulants and thrombolysis, same as DVT
DVT: Facts
- Formation of blood clots in veins depp in legs -> becomes life threatening when/if the clot breaks free
- Anticoagulant therapy often doesn’t completely remove clots -> 33% develop post-thrombotic syndrome
- Post-thrombotic syndrome: causes leg pain, difficulty walking, skin changes, and venous ulcers
DVT and PE: Facts
- Leading causes of preventable in-hospital mortality in US
- PE is most common complication of DVT
- Physiologically, occurs secondary to activation of coagulation in areas of reduced blood flow
- Most successful prophylactic regulation are anticoagulation and preventing venous stasis
Virchow’s Triad
- Venous stasis + Vessel wall injury + Hypercoagulable state
DVT: Causes
- General: Age, immobilzation, pregnancy, major surgery, long plane or car trips
- Medical: Cancer patients, CVA, MI, sepsis, ulcerative colitis
- trauma: multiple fractures, lower extremity fractures, burns, CNS injury
- Vasculitis: Lupus
- Hematologic: Factor V leiden, etc.
- Meds: chemo, IV drugs, OC’s (estrogen), menopause with estrogen replacement
DVT: Diagnosis
- Wells clinical prediction guide
- Labs:
- D-Dimer: Negative r/o; positive requires further testing
- Venous duplex US
DVT: Treatment
- Bedrest
- elevation of limb
- Compression stockings
- Pharmacotherapy w/anticoagulants or thrombolytics (prevent extension, stabilize, dissolve)
Mgmt. of DVT: Anticoagulants
- Heparin: Does not actively dissolve clots but inhibits further thrombogenesis and prevents reaccumulation of a clot after a spontaneous fibrinolysis
- Lovenox: LMWH
- Used in treatment of DVT and PE; used for prophylaxis; enhances inhibition of clotting factors and thrombin by increasing antithrombin III activity
- Average duration of treatment is 7-14d
- Generic equivalent just approved
Fondaparinux Na (Arixtra)
- For prevention of DVT/PE in at-risk patients undergoing ortho surgery
- Synthetic anticoagulant; works by inhibiting a specific clotting factor; highly predictable response
- T1/2=14-16hr
- Does not affect Pt or PTT; does not affect platelet function or aggregation
- initiate warfarin within 72hr; continue arixtra for 5d until warfarin effect established
Dalteparin (Fragmin)
- LMWH used as prophylaxis in ABD surgery and arthroplasty
Tanzaparin (Innohep)
- LMWH that inhibits clotting factors and thrombin bu increasing antithrombin
- Increases inhibition of factor Xa
- Average duration of Tx = 7-14d
Outpatient care of DVT
- Most patients w/confirmed proximal DVT may be safely treated as outpatient
- Exclusion criteria for outpatient mgmt.
- Treatment of 1st DVT is individualized
- Discharge meds
- Follow-up care and repeat Dx studies in 7d
Length of treatment: Warfarin
- PLT should be monitored and therapy d/c’d if PLT 3-6mo
- 2+ DVT -> 1yr
Treatment for PE
- Anticoagulation
- Vena cava filter
- Thrombolytic therapy
- Percutaneous thrombectomy
Complications of DVT
- PE
- Hemorrhagic complications: d/c dug, FFP or platelets, Protamine or Vk
DVT: Prognosis
- Long-term risk of chronic venous insufficiency
- ~20% of untreated (above calf) DVTs progress to PE -> 10-20% fatal -> w/anticoagulants, mortality 5-10%
- Patients w/calf DVt should be reassessed in 7 days w/US
Ankle-Brachial Index (ABI)
- Noninvasive method of diagnosing PAD
- High specificity and sensitivity
- Ratio of highest ankle SBP (measured at DP or PT with doppler on BOTH legs)
- Divided by the highest brachial SBP (must check both arms)
- NL >1 (ankle SBP>Brachial SBP in healthy pt’s)
- Resting ABI PAD
- If you calculate >1 then use lower ABI
ABI: procedure
- Patient in supine pos.
- Arms and legs at same level as heart
- Must remain lying for 10min
- Measure both side of each extremity
- Measure both DP and PT and use higher
- Divide ankle pressure by brachial pressure
ABI: Results
- 0-0.4 = severe PAD (REFER)
- 0.41-0.9 = PAD sufficient to cause claudication (refer to vascular surgery)
- 0.91-1.3 = NL (0.91-0.99: borderline -> refer for stress test)
- > 1.3 = noncompressible, severe calcification