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Peripheral Vascular Disease: “Venous” Disorders NUR 1021 MTC Spring 2016 Venous Disorders • • • • Venous thromboembolism Chronic venous insufficiency Leg ulcers Varicose veins Venous Thromboembolism • Venous thromboembolism (VTE) – One of health care's greatest challenges – Includes both thrombus & embolus complications – Millions of people in U S are affected by DVT each year – Many die from pulmonary embolism Virchow triad- 3 conditions associated with thrombus formation – Vessel damage • Damaged endothelium stimulates platelet activation & initiates the coagulation cascade – Venous stasis • Valves are dysfunctional or the muscles of the extremities are inactive – Increased blood coagulability • Occurs in blood dyscrasias or sepsis Predisposing Factors – 1. • • • • Vessel damage Direct trauma Post hip or knee replacement surgery IV catheter>48 hr Irritating meds – 2. Stasis of blood • • • • – 3. • • • Heart failure, shock Immobility; prolonged sitting Obesity, Pregnancy Constrictive clothing Hypercoagulability of blood Oral Contraceptives Malignant disease Blood dyscrasia Blood Flow and Function of Valves in Veins Incompetent valves lead to venous stasis Formation of thrombus • Frequently accompanies phlebitis – Venous thrombosis occurs more frequently in veins of lower extremities • Venous thrombi – Aggregates of platelets attached to vein wall – “tail”like appendage of fibrin, WBC’s & multiple RBC’s Venous Thrombus Grows • The “tail” can grow in direction of blood flow • Dangerous – parts of thrombus can break off and occlude pulmonary vessels Signs and Symptoms of DVT • Classic -calf or groin tenderness • Pain and sudden onset of unilateral swelling of the leg • Pain in calf on dorsiflexion of the foot (positive Homans’ sign) – False-positive findings are common • Functional impairment Assessment • Superficial vein – Assess for induration (hardening) along the blood vessel – Warmth, edema, tenderness & redness may also be present in superficial & DVT • Deep Vein Thrombosis – Edema in one extremity suggests DVT • May measure and compare right and left calf and thigh Preventive interventions • Prior hx of VTE- reoccurrence @ rate of 25% within 5 yrs – – – – – TED hose; SCD’s; venous foot pumps Leg exercise Early ambulation post-op Adequate hydration Prophylactic Lovenox s/c If DVT diagnosed: • • • • • Bedrest 5-7 days Elevate leg NO massage of leg ever Warm moist compresses Pain med Diagnosis • Venous duplex ultrasonography – Noninvasive ultrasound -assesses flow of blood in veins of the arms and legs • Impedence Plethysmography – assess venous outflow & detects most DVTs above the popliteal vein • MRI- useful in finding DVT in proximal deep veins and inferior vena cava or pelvic veins D-dimer test -global marker of coagulation activation • Lab Test- Normal results: <250 ng/mL – Measures fibrin degradation products produced from fibrinolysis (clot breakdown – Used for the diagnosis of DVT when few clinical signs – Useful as adjunct to noninvasive testing D-dimer – reasons for altered results • Negative d-dimer test – Can exclude a DVT without an ultrasound • False negative: occurs if patient on anticoagulant therapy • False positive: – Recent surgery, trauma, infection & numerous other conditions can cause a false positive Lovenox • Low molecular weight heparin, smaller molecule size • For sub-q use only- prefilled syringe • Pt may learn self-injection for home use. • Inhibits thrombin formation – Inhibits factors 11a & factor Xa More on Lovenox • Binds less to plasma proteins & has a longer half-life & more predictable response • Routine coagulation tests typically not required • Monitor complete blood count at regular intervals Drug Therapy • Anticoagulants used routinely for VTE prevention and treatment • Goal of drug therapy for VTE prophylaxis – Prevent clot formation • Goal in treatment of confirmed VTE – Prevent propagation of the clot & development of any new thrombi Prevent clot from breaking off and going to lung → Pulmonary Embolus Heparin • Action: antagonist to thrombin. – Does NOT dissolve clots • Effect is immediate and short-lived. – Inhibits Factor II • Usually used for thromboembolic episodes and vascular/cardiac surgeries, or for high risk patients – Adm. for 5 days to prevent extension of clot – Then begin oral therapy – warfarin (Coumadin) Medical Treatment • Dosage of Heparin: – Monitor aTTP Heparin IV: until therapeutic PTT levels reached, then Coumadin po. • Antidote for Heparin: Protamine sulfate (NCLEX likes to ask questions like this) Lab Tests for the Patient on Heparin • aPTT (Activated Partial Thromboplastin Time) – Normal 30-40sec – Therapeutic level is 1 1/2 to 2 1/2 times control. Care of the Patient on Heparin • IV - slow drip, based on pts weight and aPTT results. • May give sub-q in abdomen • Monitor for bleeding- No razors • Care when brushing teeth • Don’t take ASA products • Monitor for hematuria & blood in stool NCLEX Challenge • The client is receiving heparin therapy for a venous thromboembolism (VTE). Which activated partial thromboplastin time (aPTT) indicates that anticoagulation is adequate? • a. The client’s aPPT is half of the control value. • b. The client’s aPPT is the same as the control value. • c. The client’s aPPT is twice the control value. • d. The client’s aPPT is five times the control value. NCLEX Challenge • A client who is receiving unfractionated heparin is experiencing excessive bleeding. Which medication will the nurse administer? • a. Warfarin • b. Vitamin K • c. Enoxaparin • d. Protamine sulfate Coumadin (warfarin) • Slows down liver’s • PT (Prothrombin production of Vit. K Time) must be 1 1/2 to 2 times • Long term therapy: normal (11 - 13) to 3-6 months be at a therapeutic • Oral: 2-5mg/day level. • Use INR & PT to • Antidote: Vitamin K monitor therapy injection Food-Drug Interaction • Patients on Coumadin – Encouraged to limit dietary intake of green leafy vegetables, i.e. spinach →contain a lot of Vit K • Knowing what we know about Vit K and the synthesis of prothrombin, what is the problem if the patient takes in a lot of Vit K in foods? INR – International Normalized Ratio – What is it? • A specific thromboplastin reagent used to achieve clot formation – affects the amount of time it takes to form the clot. • A patient on coumadin used to have great variations in the Protimes when done by different laboratories. INR continued… • To avoid these variations, the WHO developed INR to standardize PT test • Developed a thromboplastin from human brain that became the standard – Normal = 0.75-1.25 • Venous thromboembolism: – Target INR range 2.0–3.0 Self-Monitoring of INR • Self-monitoring – Gold standard of care – Individuals using self monitoring remain within therapeutic range over 70% of the time Other Medical Therapy • Aspirin 81 mg/day (antiplatelet) • Fibrolytics: (dissolve clots) – Catheter-directed thrombolytics directly dissolve clot(s) & reduce the acute symptoms • Streptokinase • TPA • Urokinase – Risk of bleeding NCLEX Challenge • The health care provider has prescribed the client sodium warfarin (Coumadin) while he or she is still receiving intravenous heparin. Which is the nurse’s best action? • a. Administer the medications as prescribed. • b. Turn off the heparin drip for 1 hour before administration of the warfarin. • c. Discontinue the heparin drip completely before warfarin administration. • d. Hold the dose of warfarin. Surgical Treatment • Venous thrombectomy – Removal of a thrombus through an incision in the vein – Done if massive occlusion does not respond to medical therapy – Thrombus if 1-2 days onset – Care similar to having arterial surgery Vena cava interruption device (Greenfield filter) • Inserted percutaneously through right femoral or right internal jugular veins. • Sieve-type” obstruction Filter device is opened and spokes penetrate the vessel walls – Permits filtration of clots without interruption of blood flow Venous Ulcers • Venous insufficiency – Occurs as result of prolonged venous hypertension • Stretches veins & damages valves • Damaged valves in veins results in retrograde blood flow→ pooling of blood in the legs • Hydrostatic pressure in the veins increases and serous fluid and RBCs leak from the capillaries and venules into the tissue, resulting in edema Venous ulcers • Stasis of blood over time results in venous stasis ulcers, swelling and cellulitis – Enzymes in the tissue eventually break down RBCs, causing the release hemosiderin→ brownish discoloration – Skin of the lower leg -thick, fibrous (hard) subcutaneous tissue Venous ulcers (cont.) • Located above the medial malleolus • Often quite painful particularly when edema or infection is present • Pain may be worse when the leg is in a dependent position Care for Venous Stasis Ulcers • Compression-essential for CVI treatment, venous ulcer healing, and prevention of ulcer recurrence • Variety of options for compression therapy – Elastic wraps – Custom-fitted graduated compression stockings – Paste bandage (Unna boot) with an elastic wrap Care for Venous Stasis Ulcers (cont.) • Make sure that coexistent PAD is not present before compression therapy begun • Moist environment dressings - used in conjunction with compression therapy – More effective in hastening the healing of venous leg ulcers than dry dressings – Options include hydrocolloids, hydrogels, foams, calcium alginates, etc. Debridement with: • Wet to dry NS dressings • Enzymatic ointments (eg Silvadene, Accuzyme) and N/S dressings • Calcium alginate dressing (Sorbsan) – From seaweed. Pulls drainage away from the wound. Absorbs large amounts of drainage associated with venous ulcers. • Debrisan Beads – Absorb wound secretions, turn yellow, remove and replace q 24-48 hours. Dressings for venous ulcers: • Negative pressure dressings – Wound Vac-↓ healing time in complex wounds • Hyperbaric oxygen-use if no healing after 30 days – Enhances phagocytosis • Hydrocolloids popular choice (DUOderm) - leave on 3-5 days; Compression Treatment: • Compression Dressing or Hose – compression increases velocity of blood flow in deep veins and venous return to the heart- underlying venous ulcer problem. – Unna’s Boot - moistened gauze (Zinc Oxide) applied toes - knees, covered with elastic wrap that hardens, changed 1x wk. per NP or Dr. This leg looks pretty good yet!! Varicose Veins • Vein wall weakens & dilates • Venous pressure increases • Valves become incompetent Etiology of Varicose Veins • • • • • Heredity Pregnancy Obesity Extreme height Heart disease • Occupations with prolonged standing or sitting – nurses, hair stylists, construction workers, teachers, office workers, postal workers Pathophysiology • Vein wall weakens & dilates – – – – Venous pressure increases Valves become incompetent Vessels dilate more Veins become tortuous & distended Signs and Symptoms • • • • • • • Distended, protruding veins Muscle fatigue in lower legs Feeling fullness in legs Night cramps Pain-most prominent when standing Sx relieved by elevating legs If untreated: Chronic venous insufficiency Prevention • • • • Avoid wearing socks too tight@ top Avoid crossing legs at thighs Avoid sitting or standing for long periods Elevate legs 3-6” higher than heart when resting • Walk 1-2 miles/day • Compression stockings • Weight reduction if obese OK- This works to get the feet up!! Medical Management • Deep Veins: Must be patent in order to operate on superficial veins. • Vein Ligation and Stripping: – Saphenous system • • • • • Incise at groin Incision 2-3 cm below knee Thread wire length of vein to ligation Pull wire –stripping/removing vein Pressure & elevation minimize bleeding Post op Care • FOB elevated • ROM of legs q 1 hr • Maintain firm elastic stockings 1 week. • Do circulation checks • Keep leg elevated • Walk postop. 510min/q 1 hr first 24 hrs. • DO NOT Sit or Stand Still ! • Leg will look bruised - warn pt. • Pain control - mild analgesics A patient with visible varicose veins wants to have surgery to remove them because of leg pain. What would be the most appropriate response for the nurse to make to this patient? a. "Surgery will have a good cosmetic effect, but will not relieve the discomfort associated with varicose veins." b. "All varicose veins should be surgically removed to restore adequate blood flow to your legs and prevent gangrene." c. "Often measures such as elevating your legs and elastic stockings can relieve the discomfort associated with varicose veins." d. "Surgery is never indicated unless the varicose veins are interfering with circulation. Have you tried cosmetic measures to cover them up?" A patient is recovering from surgery for varicose veins. What information should the nurse include in this patient’s postoperative teaching? Select all that apply. 1. Elevate the extremities. 2. Increase ambulation gradually. 3. Sit for no more than 90 minutes at a time. 4. Avoid standing for more than 30 minutes. 5. Keep pressure stockings on continuously 1 week. Sclerotherapy • Cosmetic for Spider Veins • Irritating chemical - inject into vein to produce phlebitis and fibrosis. • May use after postop vein stripping • In MD office – does not require sedation • Use of foam sclerosant – Studies showing more effective in obliteration of varicose veins • Use of mild analgesic- minor burning for 1-2 days • Anti-embolism hose- 5 days • Then graduated compression hose x 5 wk. • Encourage walking Attitude is a little thing that makes a big difference. Winston Churchill