36 Nursing2003, Volume 33, Number 5 www.nursingcenter.com

Recognizing and managing

D V Td e e p v e i n t h r o m b o s i s

www.nursingcenter.com Nursing2003, May 37

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��DEEP VEIN THROMBOSIS (DVT) affects morethan 2.5 million people every year. In itself, theformation of a DVT in the leg isn’t life-threatening, but if the clot embolizes to thelungs, it can cause a pulmonary embolus (PE).A PE may be so mild that the patient doesn’teven notice symptoms, or severe enough tocause an immediate cardiac arrest.

Identifying and treating DVT before a life-threatening complication develops is crucial. Inthis article, I’ll review the pathophysiology, riskfactors, and causes of DVT, plus your role inassessment and patient teaching.

Pathophysiology of DVTOriginating in a deep vein, DVT usually occursin the lower leg. However, it may also affect an arm in the presence of anindwelling venous catheter, compression injury to the arm, or compressionof the subclavian vein by a rib.

Various factors influence blood flow through the legs. Veins, whichreturn blood to the heart, are designed for unidirectional blood flow; valvesin the veins prevent blood backflow, which would cause blood to pool anddistend the veins. When people stand, the pressure exerted by the columnof blood easily exceeds the pressure of the blood coming through the capil-lary bed into the venous system. However, when their calf muscles tighten—for example, when they walk—they compress the tissue around theveins, increasing pressure and moving venous blood up the leg. With pro-longed immobility, the normal pump action of the calf muscles is lost,putting patients at risk for venous stasis and DVT formation.

Three causes of troubleDVT rarely occurs in the absence of certain risk factors. Knowing whatthey are will help you identify patients at risk and perform a more focusedphysical examination.

Virchow’s triad—changes in blood coagulability, changes in the vesselwall, and changes in blood flow—are the three main factors linked to DVTdevelopment. (For more details, see A Closer Look at Virchow’s Triad.) Themore risk factors present, the more likely that a DVT will develop.

Because a DVT inevitably causes vein inflammation, both thrombosis andthrombophlebitis are used to describe the process. The inflammation mayalso destroy the valves involved, contributing to postthrombotic syndrome,a chronic inflammation of the affected veins that develops in 40% to 60%

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of patients with DVT.However, if the thrombus doesn’t

completely occlude the vein andthe patient has adequate collateralcirculation, he may remain asymp-tomatic: More than 50% of DVTsdon’t cause symptoms initially. Thefirst hint of trouble for somepatients is the sudden onset ofunexplained tachycardia, tachy-pnea, anxiety, and hypoxia, indicat-ing a PE. Although the mortalityassociated with PE is variable, itcan be as high as 25%.

A careful history and physicalassessment may help you detectsubtle clinical evidence of DVTbefore your patient develops PE or

another dangerous complication.One of the most reliable physical

findings in DVT is unilateral edemaof the affected leg. Measure bothlegs at midthigh and midcalf andcompare the circumferences to eachother and to earlier measurements.An initial finding of a difference incircumference between the left andright leg may not be significant, butany increase in circumferenceshould be reported and document-ed. Other common physical signsof DVT include warmth and ery-thema of the affected extremity.

The patient may experience pain or tenderness in the calf inresponse to movement or pressureor when he stands. Homans’ sign—increased resistance or pain thatoccurs in the calf on forced dorsi-flexion of the foot—has been his-torically considered an indicationof DVT, but it’s an unreliable diag-nostic sign: Calf pain from muscu-lar injury will also elicit Homans’sign.

Testing, testingBecause many DVTs are difficult todetect clinically, diagnostic studies

may be indicated. One of the sim-plest is duplex venous ultrasonog-raphy, which may be performed atthe bedside. Ultrasound imagerycan reveal a thrombus in a deepvein; the Doppler ultrasound mea-sures the blood flow velocity inveins and can detect flow abnor-malities.

Although a duplex study is non-invasive and relatively simple toperform, its accuracy dependsupon the technician’s skill. If theultrasound is negative for DVT andthe health care team still suspectsthat the patient has DVT, avenogram may be indicated tomake a definitive diagnosis.

Magnetic resonance imaging(MRI) is another noninvasivestudy that can be used to detectDVT in the proximal deep veins.Whether to use this test or a veno-gram depends on the patient’s clin-ical findings; MRI is more usefulthan venography in patients withsuspected DVT of the inferior venacava or pelvic veins.

Although it’s being replaced byultrasound, the venogram is stillconsidered by many health careproviders to be the gold standardfor diagnosing DVT. During thisinvasive test, the patient is placedon a fluoroscopic table that’s usual-ly tilted 45 degrees, and a contrastmedium is injected into a superfi-cial foot vein. A clinician observesthe flow of contrast medium byfluoroscopy and takes X-rays; if thecontrast doesn’t fill the veins nor-mally, acute DVT is confirmed.

Complications of venographyinclude hypersensitivity reactionsto the contrast medium, acuterenal failure because of the volumeof contrast medium used, andextravasation of the contrast medi-um (especially in patients with a

history of arterial insufficiencybecause of tissue necrosis andulceration). The risk of acute renalfailure is higher in the elderly andin patients with diabetes, hyper-uricemia, or multiple myeloma.

Postprocedural thrombophle-bitis, another possible complica-tion, is related to the concentrationand osmolality of the contrastmedium used and the length oftime it was in contact with thevenous endothelium.

A D-dimer test is a blood test tomeasure fibrin degradation frag-ments generated by fibrinolysis.Elevated D-dimer levels indicate athrombotic process but aren’t spe-cific to DVT. This test is useful asan adjunct to noninvasive testing.If the patient has a low clinicalprobability of DVT and a negativeD-dimer, DVT can be ruled outwithout an ultrasound.

Clot-busting strategiesTreatment for DVT has three goals:to prevent PE, halt further throm-bus formation, and dissolve theexisting thrombus by letting thebody’s own fibrinolytic systemwork.

Effective, prompt treatment sig-nificantly decreases the likelihoodof future episodes of DVT, whichcan occur in up to 33% of patientswithin 5 years. Treatment also mayprevent the development of post-thrombotic syndrome.

The cornerstone of DVT treat-ment is dose-adjusted, intravenous(I.V.) unfractionated heparin,which prevents the formation ofnew thrombi and growth of theexisting thrombi.

Baseline serum lab values suchas activated partial thromboplastintime (aPTT), prothrombin time(PT), international normalizedratio (INR), and platelet countsmust be obtained. The goal ofheparin therapy, according to theAmerican College of Chest Physi-cians (ACCP) guidelines, is tomaintain the aPTT between 1.5and 2.3 times the mean normal.

38 Nursing2003, Volume 33, Number 5 www.nursingcenter.com

Although it’s being replaced by ultrasound, the venogram

is still considered by many health care providers to be the

gold standard for diagnosing DVT.

The other lab values are drawn toidentify bleeding problems. Makesure you check the patient’s historyfor any contraindications toheparin therapy, such as a historyof heparin-induced thrombocy-topenia (HIT), recent trauma, orsurgery.

The ACCP guidelines recom-mend giving 5,000 units of I.V.heparin to patients with suspectedDVT. Once DVT is confirmed,give another 80 units/kg, followedby a maintenance infusion of 18units/kg. Check the patient’s aPTTlevel after 6 hours and adjust theheparin dosage to maintain a ther-apeutic level of 1.5 to 2.3 timesthe mean normal. Recheck theplatelet count between days threeand five.

Bleeding is the major risk withanticoagulant use, and increasedheparin doses and age over 70increase the risk. Most patientsreceiving anticoagulation areadvised to take acetaminophen forpain or fever because of its relativesafety compared with aspirin,which has an antiplatelet effect.Patients who’ve received epiduralor spinal anesthesia, or who havean epidural catheter for analgesia,are at risk for developing epiduralor spinal hematomas when on anti-coagulants, so the ACCP recom-mends using anticoagulant pro-phylaxis or therapy with caution inthese patients.

Another possible complication,HIT, is caused by an immuneresponse to heparin that damagesplatelets. Heparin-induced throm-

bocytopenia may develop in 1 to 2weeks in patients who haven’t beenpreviously exposed to heparin; inpatients who have been previouslyexposed, it may develop in as littleas 24 hours.

Low-molecular-weight heparins(LMWHs), such as dalteparin andenoxaparin, are considered as safeand effective as unfractionatedheparin. Because they don’t requireI.V. access or aPTT or PT monitor-ing, they’re more convenient touse. Given subcutaneously (S.C.),the LMWHs have a more pre-dictable dose-response relation-ship, offer weight-adjusted dosingwithout the need for lab monitor-ing, and can be given just once ortwice a day on an outpatient basisto treat and prevent DVT.

Oral warfarin therapy should bestarted on the first day of LMWHtherapy, with the dose adjusted tomaintain the patient’s INR in thetherapeutic range. After 4 or 5days, the LMWH can be discontin-ued.

Before beginning therapy withan LMWH, obtain the same base-line serum lab values as for therapywith unfractionated heparin. TheLMWHs are contraindicated inpatients with HIT or other con-traindications to heparin therapy.Although the LMWHs are less like-ly than unfractionated heparin totrigger HIT, you still must monitorfor this and other possible compli-cations. The ACCP recommendschecking the patient’s plateletcount between days three and fiveof LMWH therapy.

After heparin, warfarin Initiate treatment with an oral anti-coagulant, such as warfarin, within24 hours after beginning treatmentwith unfractionated heparin orLMWH. You can give it through anenteric tube if the patient can’tswallow. After 4 to 5 days of com-bined therapy, heparin can bestopped if the patient’s INR isgreater than 2 (the goal is an INRof 2.5; the INR should be in therange of 2 to 3). Warfarin stopsclot formation by inhibiting clot-ting factors that are dependent onvitamin K. But it doesn’t take fulleffect for 3 to 4 days, which is whythe patient needs treatment withheparin or an LMWH initially.

Typically, the patient takes aninitial warfarin dose of 5 mg, fol-lowed by individualized doses asguided by the INR results. Mostpatients continue warfarin therapyfor 3 to 6 months, althoughsome—for example, those withrecurrent DVT or a continuing riskfactor such as cancer—may use itfor 12 months or longer.

A recent study in The NewEngland Journal of Medicine foundthat low-dose warfarin therapywith a target INR of 1.5 to 2.0 ishighly effective in preventingrecurrent DVT, without raising therisk of hemorrhage or stroke.

Like anticoagulants, warfarinmay cause bleeding, so monitor thepatient’s INR closely and watch forbleeding.

Fibrinolytic agents, such asstreptokinase and tissue plasmino-gen activator, have been used with

www.nursingcenter.com Nursing2003, May 39

A closer look at Virchow’s triad

Changes in blood coagulability

Changes in the vessel wall

Changes in blood flow

Common causes• Traumatic, burn, and surgical injuries, because of tissue damage, release of tissue factors,and activation of the extrinsic pathway of coagulation• Cancer, because fibrinolytic activity may be reduced and because malignant tissue maypromote coagulation• Atherosclerotic changes leading to rupture of plaque on the vessel wall exposes thrombo-genic material, activating platelets and the coagulation cascade.• Stasis related to prolonged immobility, paralysis, varicose veins, or heart failure• Increased blood viscosity

heparin to treat some patients withvenous thromboembolic disease.According to the ACCP, the bestcandidates are patients with hemo-dynamically unstable PE or mas-sive ileofemoral thrombosis. Anysystemic fibrinolytic therapy cancause bleeding.

Another option is catheter-directed fibrinolysis, in which thephysician imbeds a catheter intothe thrombus and infuses a fibri-nolytic agent, avoiding the risksassociated with systemic fibrinolyt-ic therapy. Recently, percutaneousmechanical thrombectomy hasbeen evaluated as an adjunct tocatheter-directed fibrinolysis; this

technique may be effective with alower dose of fibrinolytic agent anda shorter infusion. When anticoag-ulant therapy is contraindicated orcauses complications, or in cases ofrecurrent DVT despite adequateanticoagulation, the physician mayplace an inferior vena cava filter toprevent thrombi from migratinginto the lungs. Complicationsinclude puncture site bleeding; PEand inferior vena cava occlusionare rare if the filter has been prop-erly placed.

Your roleBecause most patients with DVTare treated with anticoagulants,monitor closely for bleeding. Anychange in level of consciousnessmay indicate intracranial bleeding.Also evaluate for minor bleeding inthe urine or stool or from the skinor nose. Bloody vomit indicatesbleeding in the upper gastrointesti-nal tract. If the patient is receivingheparin, make sure protamine sul-fate is readily available to reverseheparin’s effect if excessive bleed-ing occurs. Also monitor theplatelet count for signs of HIT.

If the patient will be receivingLMWHs as an outpatient, he (or acaregiver) must know how to giveS.C. injections. Explain why hemust continue the injections forthe time ordered by the prescriber.

Obtain a detailed history of allmedications (prescription drugs,over-the-counter products, andherbal or nutritional supplements)for patients on warfarin becausethis drug interacts with many med-ications and foods.

If an interaction inhibits war-farin’s effect, the patient is at anincreased risk for DVT and PE. Ifan interaction enhances warfarin’seffects, he’s at increased risk for

bleeding. Teach him what he needsto know for safe, effective use ofwarfarin and tell him to talk withhis health care provider beforestarting any new medication. Healso needs regular follow-up test-ing.

Warfarin can cause potentiallyfatal necrosis of the skin and othertissues, although this is rare. Thisreaction usually occurs within 10days of the start of therapy, so tellthe patient to call his health careprovider immediately if he noticesany painful skin areas or suddenchanges (such as bruising or dark-ening of the skin). Tissue damageoccurs principally at sites withfatty tissue, such as the abdomen,breasts, buttocks, and thighs.

Preventing DVTBecause diagnosing DVT can bedifficult, many providers order pro-phylactic therapy for patients athigh risk, such as those undergo-ing major orthopedic surgery. Oneof the simplest ways to preventDVT is by encouraging earlyambulation after surgery. However,if the surgery lasts more than 45

minutes, thrombus formation mayhave a head start. Don’t rely onearly ambulation alone to preventDVT in a surgical patient, unlesshe’s under age 40, has no other riskfactors, and will undergo surgerylasting less than 45 minutes.

To reduce the risk of DVT, applygraduated compression stockingsbefore surgery and have the patientwear them continuously until he’sfully ambulatory. (These stockingsalso are used for patients after anacute DVT resolves, to increasevenous flow and reduce swelling.)

Another option for DVT preven-tion is intermittent pneumaticcompression devices, which com-press the leg and increase venousflow, decreasing venous poolingand stasis. The devices typicallyhave two or three chambersimbedded in a sleeve that wraparound the leg. The devices mimicthe venous pumping action of thecalf muscles by alternately com-pressing the leg and then relaxing.Some of these devices use asequential pattern of compression,starting at the ankle and movingup the leg. Correct sizing andapplication are crucial to success-ful use (see “Get Pumped Up toPrevent DVT” in the Septemberissue of Nursing2002).

A relatively new device for theprevention of DVT is the venousplexus foot pump. The pump mim-ics the natural action of walking byintermittently compressing the soleof the foot and then relaxing it, sothe venous plexus can fill withblood. Several studies have demon-strated that the venous plexus footpump is very effective in prevent-ing DVT formation in orthopedicpatients. Its use in other situationsand in combination with heparinand LMWHs is being studied.

All these preventive measuresenclose some portion of the leg orfoot. Remove them regularly toassess the skin for redness orbreakdown. Don’t use the compres-sion devices or the venous plexusfoot pump on patients with an

40 Nursing2003, Volume 33, Number 5 www.nursingcenter.com

A relatively new device for the prevention of DVT is

the venous plexus foot pump, which mimics the natural

action of walking.

acute DVT, significant peripheralvascular ischemia, large openwounds or skin grafts, or cancer ofthe extremity. If the devices weren’tapplied at onset of bed rest or dur-ing surgery, obtain a duplex ultra-sonogram before applying them, torule out a DVT.

Low-dose unfractionated heparinand LMWH also are used to preventDVT. When using heparin prophy-lactically, the usual regimen is 5,000units S.C. just before surgery andcontinued every 8 to 12 hours untilthe patient is discharged. This low-dose schedule of heparin adminis-tration doesn’t require lab monitor-ing because it has a very limitedeffect on the aPTT level and bleed-ing risk. Contraindications toheparin for DVT prevention includea previous hypersensitivity reactionto heparin or HIT.

An LMWH also can be givenS.C. just before surgery. Therapycontinues once or twice a day untilthe patient is discharged. Dosingregimens for each of the LMWHsare specific to each medication andvary according to patient risk leveland the type of surgery or injury.Low-dose unfractionated heparin

and LMWH can be used withmechanical methods in patients atmoderate to high risk for DVT.

Warfarin, 5 mg, may be giventhe day of or the day after surgery.Subsequent daily doses are adjust-ed to achieve a target INR of 2 to 3by the fifth day. The patient shouldcontinue warfarin for at least 6weeks and possibly for as long as 6months.

Encourage your patient to engagein activity that will decrease theincidence of DVT, such as earlyambulation and active leg exercis-es. Monitor for adequate fluidintake to prevent dehydration andchanges in blood flow. Teach thepatient to lower his risk of DVT byavoiding:• any constricting clothing on thelegs that might decrease venous flow• sitting with knees bent or crossedfor long periods • standing for long periods.

Remind him that long car or air-plane trips can increase the risk ofDVT, so he should stay wellhydrated and move around when-ever possible or do leg exerciseswhile sitting. By teaching yourpatient how to avoid problems,

you may be able to help him avoidDVT in the future.SELECTED REFERENCESAmerican College of Chest Physicians: “SixthACCP Consensus Conference on Antithrom-botic Therapy,” Chest. 119(1, Suppl.):1S-370S,January 2001.

Aquila, A.: “Deep Venous Thrombosis,” Journalof Cardiovascular Nursing. 15(4):25-44, July2001.

Byrne, B.: “Deep Vein Thrombosis Prophylaxis:The Effectiveness and Implications of Using Below-Knee or Thigh-Length Graduated Com-pression Stockings,” Heart & Lung. 30(4):277-284, July/August 2001.

Dolovich, L., et al.: “A Meta-Analysis Compar-ing Low-Molecular-Weight Heparins with Un-fractionated Heparin in the Treatment of Ve-nous Thromboembolism: Examining SomeUnanswered Questions Regarding Location ofTreatment, Product Type, and Dosing Fre-quency,” Archives of Internal Medicine.160(2):181-188, January 24, 2000.

Ridker, P., et al.: “Long-Term, Low-IntensityWarfarin Therapy for the Prevention of Recur-rent Venous Thromboembolism,” The NewEngland Journal of Medicine. 348(15):1425-1434, April 10, 2003.

Michael W. Day is outreach educator and clinicalnurse specialist for Northwest MedStar in Spokane,Wash., and a staff nurse in the intensive care unit ofSacred Heart Medical Center in Spokane.

www.nursingcenter.com Nursing2003, May 41

University of Massachusetts Medical SchoolCenter for Outcomes Researchhttp://www.umassmed.edu/outcomes/dvt

Deep Vein Thrombosis Hubhttp://www.projectlinks.org/thrombosis

Last accessed on April 1, 2003.

SELECTED WEB S ITES

CE Test

Recognizing and managing deep vein thrombosis

Instructions:• Read the article beginning on page 36.• Take the test, recording your answers in the test answerssection (Section B) of the CE enrollment form. Each question has only one correct answer.• Complete registration information (Section A) and courseevaluation (Section C).• Mail completed test with registration fee to: LippincottWilliams & Wilkins, CE Dept., 16th Floor, 345 Hudson St.,New York, NY 10014.• Within 3 to 4 weeks after your CE enrollment form isreceived, you will be notified of your test results.• If you pass, you will receive a certificate of earned contacthours and an answer key. If you fail, you have the option oftaking the test again at no additional cost.• A passing score for this test is 12 correct answers.• Need CE STAT? Visit http://www.nursingcenter.com forimmediate results, other CE activities, and your personalizedCE planner tool. • No Internet access? Call 1-800-933-6525, ext. 331 or ext.332, for other rush service options.• Questions? Contact Lippincott Williams & Wilkins: (212)886-1331 or (212) 886-1332.

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Provider Accreditation:This Continuing Nursing Education (CNE) activity for 2.0 contact hoursand 0.5 pharmacology contact hour is provided by Lippincott Williams &Wilkins, which is accredited as a provider of continuing education innursing by the American Nurses Credentialing Center’s Commission onAccreditation and by the American Association of Critical-Care Nurses(AACN 9722, CERP Category A). This activity is also provider approvedby the California Board of Registered Nursing, Provider Number CEP11749 for 2.0 contact hours and 0.5 pharmacology contact hour. LWW isalso an approved provider of CNE in Alabama, Florida, and Iowa andholds the following provider numbers: AL #ABNP0114, FL #FBN2454, IA#75. All of its home study activities are classified for Texas nursing con-tinuing education requirements as Type I.

Your certificate is valid in all states. This means that your certificate ofearned contact hours is valid no matter where you live.

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1. Which statement is correct about DVT?a. The formation of a DVT is in itself life-

threatening.b. If the clot embolizes to the lungs, it can cause a

PE.c. DVT usually occurs in the arms.d. DVT frequently occurs in the absence of certain

risk factors.

2. Which statement is correct about veininflammation caused by DVT?a. Postthrombotic syndrome develops in 40% to

60% of patients with DVT.b. The term thrombophlebitis shouldn’t be used to

describe the process.c. Inflammation doesn’t affect vein valves.d. Postthrombotic syndrome is an acute inflam-

mation of the affected veins.

3. Which statement best describes clinicalmanifestations of DVT?a. 25% of DVTs don’t cause symptoms initially.b. The mortality rate associated with PE can be as

high as 50%.c. A sudden onset of unexplained tachycardia, tachy-

pnea, anxiety, and hypoxia may indicate a PE.d. DVTs are always symptomatic.

4. One of the most reliable physical findingsin DVT isa. bilateral leg swelling.b. Homans’ sign.c. unilateral leg edema.d. pallor of the affected extremity.

5. Which statement is correct about Homans’sign?a. It’s characterized by pain or tenderness in the

thigh in response to movement or pressure.b. It’s elicited by forced plantar flexion of the foot.c. It’s a reliable diagnostic sign for DVT.d. Calf pain from muscular injury will also elicit

Homans’ sign.

6. Which statement best describes duplexvenous ultrasonography?a. It’s an invasive diagnostic study.b. It’s relatively complex to perform.c. Its accuracy doesn’t depend on the techni-

cian’s skill.d. It’s one of the simplest diagnostic studies to

perform.

7. Which technique is considered the goldstandard for diagnosing DVT?a. ultrasound imaging c. MRIb. venography d. Doppler flow study

8. Contrast medium extravasation duringvenography can have more serious conse-quences in patients witha. diabetes. c. hyperuricemia.b. arterial insufficiency. d. multiple myeloma.

9. Which statement is correct about a D-dimer test?a. Elevated levels are specific to DVT.b. Decreased levels indicate a thrombotic

process.c. It’s a useful adjunct to noninvasive testing for

DVT.d. It measures venous blood viscosity.

10. According to the ACCP guidelines, thegoal of heparin therapy is to maintain theaPTT betweena. 1.5 and 2.3 times the mean normal.b. 2.5 and 3.3 times the mean normal.c. 3.5 and 4.3 times the mean normal.d. 4.5 and 5.3 times the mean normal.

11. The ACCP guidelines recommend givingpatients with suspected DVT a. 1,000 units of I.V. heparin.b. 3,000 units of I.V. heparin.c. 4,000 units of I.V. heparin.d. 5,000 units of I.V. heparin.

12. Once DVT is confirmed, the ACCP guide-lines recommend a maintenance heparin infu-sion ofa. 10 units/kg. c. 20 units/kg.b. 18 units/kg. d. 38 units/kg.

13. The major risk associated with anticoagu-lation use isa. bleeding. c. HIT.b. epidural hematoma. d. spinal hematoma.

14. Using LMWHs to treat a patient with DVTa. requires I.V. access for administration.b. offers weight-adjusted dosing without the

need for lab monitoring.c. requires weekly PT monitoring.d. has a less predictable dose-response relation-

ship.

15. Which statement is correct about oralwarfarin therapy in DVT?a. It’s initiated 72 hours after beginning treatment

with unfractionated heparin or LMWH.b. Heparin can be stopped after 4 to 5 days of

combined therapy with warfarin if the patient’sINR is between 1.5 and 2.

c. The typical initial dose is 5 mg, followed byindividualized doses as guided by the INRresults.

d. Most patients continue therapy for 12 monthsor longer.

16. Which of the following mimics the venouspumping action of the calf muscles?a. inferior vena cava filterb. intermittent pneumatic compression devicec. venous plexus foot pumpd. graduated compression stockings

17. Cancer can cause changes in which compo-nent of Virchow’s triad?a. blood coagulability c. blood flowb. vessel walls d. blood viscosity

Recognizing and managing deep vein thrombosisGENERAL PURPOSE To provide a comprehensive understanding of DVT. LEARNING OBJECTIVES After reading the preceding article and taking this test, you should beable to: 1. Explain the pathophysiology and clinical manifestations of DVT. 2. Identify diagnostic tests used to confirm DVT. 3. Outline management strategies for a patientwith DVT.

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