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 ThrombosisEtiology

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 ThrombosisPathophysiology

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 ThrombosisComplications

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 ThrombosisDiagnosis

Venous Doppler Evaluation

Duplex Scanning Combination of ultrasound imaging &

doppler

Venogram

Venous ThrombosisMedical 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 ThrombosisMedical 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 ThrombosisMedical 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 ThrombosisNursing Diagnoses

Top Priority Nursing Diagnosis and

the rationale

Venous ThrombosisNursing 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 ThrombosisTreatment Goals

Relief of pain Decreased edema Intact skin No complications from anticoagulation

therapy No evidence of pulmonary edema

Venous ThrombosisNursing 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 EmbolismDefinition / Demographics

Definition:

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 EmbolismEtiology

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 EmbolismClinical 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 EmbolismDefinition / Demographics

Definition:

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 EmbolismDiagnostic 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 EmbolismDiagnostic 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 EmbolismTreatment 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 EmbolismDrug 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 EmbolismSurgical Treatment

Pulmonary embolectomy – rarely done

Intracaval Filter – Greenfield stainless steel filter

Pulmonary EmbolismSurgical Treatment

Greenfield Filter

Pulmonary EmbolismNursing 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 TherapyBolus 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 =

5920unitsStep 3 – calculate mL dosage

1000U : 1ml :: 5920 u : X mL 1000U x XmL = 5920U - bolus X mL = 5920 / 1000 = 5.9 mL bolus

Heparin TherapyFlow 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