peripheral vascular disorders venous thrombosis
TRANSCRIPT
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