Peripheral Vascular Disorders Venous Thrombosis

Peripheral Vascular Disorders Venous Thrombosis Most common disorder of the veins Thrombus formation associated with inflammation Superficial – occurs in 65% of patients receiving IV therapy Deep Vein Thrombosis Iliac or femoral vein 5% of all postoperative patients

Venous Thrombosis Etiology Etiology - Virchow’s Triad Venous stasis Atrial fibrillation, obesity, immobility, pregnancy Endothelial damage Trauma, external pressure, IV caustic substances Hypercoagulability of the blood Hematologic disorders – polycythemia, severe anemias, malignancies, sepsis, use of contraceptives, smoking

Venous Thrombosis Pathophysiology Thrombus formation: RBCs, WBCs, platelets & fibrin Valvular cusps of veins Clot increased in size – develops a “tail” Partial occlusion Complete occlusion May detach and become “embolus” – travels through larger vessels then lodges in pulmonary circulation

Peripheral Vascular Disorders Venous Thrombosis Clinical Manifestations Unilateral leg edema, extremity pain, warm skin, erythema, fever, tenderness on palpation + Homan’s Sign: pain on forced dorsiflexion of the foot when the leg is raised – unreliable sign – late and appears in only 10% of the patients If the inferior vena cava is involved – lower extremities edematous and cyanotic If the superior vena cava is involved – upper extremities, back, neck and face show signs

Venous Thrombosis Complications Pulmonary Emboli Life threatening Chronic venous insufficiency Valvular destruction, retrograde blood flow Persistent edema, increased pigmentation, secondary varicosities, ulceration, dependent position cyanosis Phlegmasia cerulea dolens – rare Sudden occurrence - edematous cyanotic painful leg May result in gangrene

Venous Thrombosis Diagnosis Venous Doppler Evaluation Duplex Scanning Combination of ultrasound imaging & doppler Venogram

Venous Thrombosis Medical Management Prevention & Prophylaxis At risk patients – AROM/PROM Exercise; ambulation; elastic compression hose; intermittent compression devices (venodynes); low molecular weight (LMWH) anticoagulation Non-pharmacologic Bedrest with leg elevated; custom fit support hose

Venous Thrombosis Medical Management Drug Therapy Anticoagulation Prevention of clot propagation & development of new clots or embolization Does not dissolve the present clot Heparin Inhibits Factor IX & potentiates the action of antithrombin III – Intrinsic Clotting Pathway Inhibits thrombin-mediated conversion of fibrinogen to fibrin Coumadin Inhibits hepatic synthesis of Vitamin K-dependent coag factors II, VII, IX, & X

Venous Thrombosis Medical Management Anticoagulation Heparin – intravenous infusion APTT Activated partial thromboplastin time 24-36 sec Therapeutic: 46 – 70 sec Antidote: Protamine Sulfate Coumadin -- oral PT Prothrombin Time compared with INR International normalized ratio 0.75 – 1.25 Therapeutic: 2-3 Antidote: Vitamin K Overlapping Heparin & Coumadin Therapies Coumadin takes 2-3 days to achieve therapeutic level

Venous Thrombosis Nursing Diagnoses Top Priority Nursing Diagnosis and the rationale

Venous Thrombosis Nursing Diagnoses Acute pain r/t venous congestion impaired venous return, and inflammation Potential complication: bleeding r/t anticoagulant therapy Ineffective health maintenance r/t lack of knowledge Potential complication: pulmonary embolism r/t thrombus, dehydration, immobility

Venous Thrombosis Treatment Goals Relief of pain Decreased edema Intact skin No complications from anticoagulation therapy No evidence of pulmonary edema

Venous Thrombosis Nursing Process Assess: Hemodynamic status; peripheral vascular assessment; anticoagulation side effects; anticoagulant lab values; assess for interacting medications; assess for complications Nsg Action: Administer meds & adjust according to specific times; Avoid trauma; skin protection; proper body positioning; referrals as needed Pt/Family Education: Long-term anticoagulation therapy; DVT prevention

Venous Thrombosis Heparin – antidote? Coumadin – antidote?

Pulmonary Embolism Definition / Demographics Blockage of pulmonary artery by thrombus, fat, or air emboli Most common complication of hospitalized patients 650,000 in USA per year 50,000 deaths per year

Pulmonary Embolism Etiology Presence of unsuspected DVT Originate from femoral or iliac veins Most common mechanism: Jarring of the thrombus by mechanical forces – sudden standing, changes in the rate of flow, e.g., Valsalva Fat embolism – fractured long bones / pelvis Air embolism – improper IV therapy

Pulmonary Embolism Clinical Manifestations Severity depends on the size Sudden onset of: dyspnea tachypnea tachycardia Other S&S: cough, pleuritic chest pain, rales, fever, hemoptysis, change in mental status

Pulmonary Embolism Definition / Demographics Blockage of pulmonary artery by thrombus, fat, or air emboli Most common complication of hospitalized patients 650,000 in USA per year 50,000 deaths per year

Pulmonary Embolism Diagnostic Studies Ventilation – Perfusion Lung Scan Perfusion scanning: IV injection of radioisotope – detects adequacy of pulmonary circulation Ventilation scanning: inhalation of radioactive gas (xenon) – detects distribution gas through the lung fields – may not be able to be done in critically ill patients Pulmonary Angiography – peripheral catheter advanced into pulmonary artery – contrast media allows visualization of pulmonary circulation & location of embolus Computerized tomography – multislice spiral views Arterial Blood Gas Analysis – respiratory alkalosis

Pulmonary Embolism Diagnostic Studies D-Dimer Test: Assists in the detection and evaluation of pulmonary embolism Plasma study/blue top tube Increased result: arterial or venous thrombus, DVT; DIC; Pulmonary embolism; recent surgery; secondary fibrinolysis Evaluate test results in relation to pt’s signs and symptoms; medications- (Warfarin—causes decrease) <250ng/mL– within normal range

Pulmonary Embolism Treatment Goals Prevent further growth or multiplication of thrombi in the lower extremities Prevent embolization from the upper or lower extremities to the pulmonary vascular system Provide cardiovascular support

Pulmonary Embolism Drug Therapy Anticoagulation Therapy** Immediate Prevention: Heparin by infusion Therapy adjusted according to PTT Long Term Prevention: Coumadin (Warfarin) Therapy adjusted according to INR Thrombolytic Therapy – tPA – dissolves PE and the source of the thrombus ** May be contraindicated – blood dyscrasias, hepatic dysfunction, overt bleeding, hx of hemorrhagic stroke

Pulmonary Embolism Surgical Treatment Pulmonary embolectomy – rarely done Intracaval Filter – Greenfield stainless steel filter

Pulmonary Embolism Surgical Treatment Greenfield Filter

Pulmonary Embolism Nursing Diagnosis Impaired tissue perfusion Pain Anxiety Knowledge Deficit Potential for Injury related to anticoagulation

Pulmonary Embolism Nursing Process Assess: observe effects of anticoagulation; monitor anticoagulation level hemodynamic status: VS, PO, cardiac monitoring, hemodynamic monitoring—arterial & PAWP Nsg Action: HOB elevated; Administer oxygen; energy conservation Pt Education: Rationale for all treatments; anticoagulation therapy – long term

Pulmonary Embolism Heparin – Type of Blood Monitoring? Coumadin – Type of Blood Monitoring?

Heparin Therapy Bolus in Units and mL IV Push A patient with deep vein thrombosis who weighs 163 pounds is ordered to have a heparin bolus of 80 units per kg followed by an infusion. Calculate the dosage of the heparin bolus to be administered. USE HEPARIN BOTTLE 1,000 u/ mL- RN mixes Step 1 – convert pounds to kilograms: 163 / 2.2 = 74 kgs. Step 2 – calculate dose in units: 74 x 80 = 5920units Step 3 – calculate mL dosage 1000U : 1ml :: 5920 u : X mL 1000U x XmL = 5920U - bolus X mL = 5920 / 1000 = 5.9 mL bolus

Heparin Therapy Flow rate in mL/hr Order: Heparin 2,500 U per hr via IV pump from Heparin 50,000U in 1,000mL D5W. Use Heparin Bottle 25,000U/mL – mixed by Pharmacy Calculate the flow rate. Show all math. Step 1: U/mL: 50,000 / 1,000 = 50 U/mL Step 2 – 50U : 1 mL :: 2,500U : XmL 50x = 2,000 X = 2,500 / 50 X = 50mL/hr

Heparin Therapy Amount in Units/Hour A patient is receiving 20,000 units of heparin in 1,000 mL of D5W by continuous infusion at 30mL/hr. What heparin dose is he receiving? Use Heparin Bottle 25,000U/mL – mixed by Pharmacy 20,000 u : 1,000 :: XU : 30mL 1,000mL x XU = 20,000U x 30mL 1,000 x XU = 600,000 XU = 600,000 / 1,000 = 600units/hr