Deep Venous Thrombosi

8/19/2019 Deep Venous Thrombosi

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Deep Venous ThrombosisUpdated: Aug 28, 2014 link http://emedicine.medscape.com/article/1911303o!er!ie"#a"2aa$%$2$1aa

Practice Essentials

&eep !enous throm$osis '&()* is a mani+estation o+ !enous throm$oem$olism '()*. Although

most &() is occult and resol!es spontaneousl- "ithout complication, death +rom &()associated massi!e pulmonar- em$olism '* causes as man- as 300,000 deaths annuall- in the

United tates.1

Signs and symptoms

-mptoms o+ deep !enous throm$osis '&()* ma- include the +ollo"ing:

• dema ost speci+ic s-mptom

• eg pain ccurs in 506 o+ patients $ut is nonspeci+ic

• )enderness ccurs in 756 o+ patients

• armth or er-thema o+ the skin o!er the area o+ throm$osis

• linical s-mptoms o+ pulmonar- em$olism '* as the primar- mani+estation

As man- as 4%6 "ith patients "ith classic s-mptoms ha!e negati!e !enograms,2 and as man-

as 506 o+ those "ith imagedocumented !enous throm$osis lack speci+ic s-mptoms.2, 3

o single ph-sical +inding or com$ination o+ s-mptoms and signs is su++icientl- accurate toesta$lish the diagnosis o+ &(), $ut ph-sical +indings in &() ma- include the +ollo"ing:

• al+ pain on dorsi+le;ion o+ the +oot '


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)he American Academ- o+ ?amil- h-sicians 'AA?*/American ollege o+ h-sicians 'A*

recommendations +or "orkup o+ patients "ith pro$a$le &() are as +ollo"s5 :

• (alidated clinical prediction rules 'eg, ells* should $e used to estimate the pretest

pro$a$ilit- o+ !enous throm$oem$olism '()* and interpret test results

•

@n appropriatel- selected patients "ith lo" pretest pro$a$ilit- o+ &() or , it isreasona$le to o$tain a highsensiti!it- &dimer

• @n patients "ith intermediate to high pretest pro$a$ilit- o+ lo"ere;tremit- &(),

ultrasonograph- is recommended

• @n patients "ith intermediate or high pretest pro$a$ilit- o+ , diagnostic imaging studies

'eg, !entilationper+usion scan, multidetector helical ), and pulmonar- angiograph-* are

reuired

)he main la$orator- studies to $e considered include the +ollo"ing:

• &dimer testing

•

oagulation studies 'eg, prothrom$in time and acti!ated partial throm$oplastin time* toe!aluate +or a h-percoagula$le state

ee orkup +or more detail.

Management

)reatment options +or &() include the +ollo"ing:

• Anticoagulation 'mainsta- o+ therap-* i!aro;a$an D )his agent appears to pre!ent () recurrence as e++ecti!el- as eno;aparin

+ollo"ed $- a !itamin E antagonist and ma- $e associated "ith less $leeding 7, 8, 9 C inaddition, it appears to $e usa$le in highrisk groups

http://emedicine.medscape.com/article/1911303-workuphttp://emedicine.medscape.com/article/1911303-workup


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ndo!ascular therap- is per+ormed to reduce the se!erit- and duration o+ lo"ere;tremit-

s-mptoms, pre!ent , diminish the risk o+ recurrent (), and pre!ent ). ercutaneous

transcatheter treatment o+ &() includes the +ollo"ing:

• )hrom$us remo!al "ith catheterdirected throm$ol-sis D American ollege o+ hest

h-sicians 'A* recommends throm$ol-tic therap- onl- +or patients "ith massi!eilio+emoral !ein throm$osis associated "ith lim$ ischemia or !ascular compromise

• echanical throm$ectom-

• Angioplast-

• tenting o+ !enous o$structions

American


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Patient information: Deep vein thrombosis

(DVT (!eyond the !asics

& (@ )=@ (>(@

http://""".uptodate.com/contents/deep!einthrom$osisd!t$e-ondthe$asicsF!ie"Gprint

(enous throm$osis is a condition in "hich a $lood clot 'throm$us* +orms in a !ein. )his clot can

limit $lood +lo" through the !ein, causing s"elling and pain. ost commonl-, !enousthrom$osis occurs in the Hdeep !einsH in the legs, thighs, or pel!is ' +igure 1*C this is called a deep

!ein throm$osis, or &().

&() is the most common t-pe o+ !enous throm$osis. @E ?A)>

)here are a num$er o+ +actors that increase a personIs risk o+ de!eloping a deep !ein throm$osis.

@nherited throm$ophilia J @nherited throm$ophilia re+ers to a genetic pro$lem that causes the

$lood to clot more easil- than normal. (arious +actors in the $lood clotting process ma- $ein!ol!ed, depending on the t-pe o+ genetic pro$lem present.

An inherited throm$ophilia is +reuentl- present in people "ith a !enous $lood clot 'ie,

throm$us*. ?or e;ample, de+iciencies o+ antithrom$in, protein , or protein can $e +ound in

appro;imatel- 5 percent o+ patients "ho ha!e had a !enous $lood clot and are less than 50 -earso+ age. ther +actors, such as +actor ( eiden or the prothrom$in gene mutation, are +ound in up

to 5 percent o+ other"ise health- aucasians and can occur in appro;imatel- 20 to 25 percent o+ people "ith a !enous $lood clot. (enous throm$osis is in+reuent $e+ore adolescence in people"ith inherited throm$ophilia.

@+ a person is +ound to ha!e a &() and there is no kno"n medical condition or recent surger-

that could ha!e caused the &(), it is possi$le that an inherited condition is the cause. )his is

especiall- true in people "ith a +amil- mem$er "ho has also e;perienced a &() or pulmonar-em$olism. @n these cases, testing +or an inherited throm$ophilia ma- $e recommended.


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+inding an inherited throm$ophilia does not change the "a- that doctors treat the !enous

throm$oem$olism, and ma- not increase the chance o+ the $lood clot coming $ack. 'ee I?inding

the cause o+ !enous throm$osisI $elo".*

le!ated clotting +actors J


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ertain disorders o+ the $lood, such as pol-c-themia !era or essential throm$oc-themia

Antiphospholipid anti$odies 'anti$odies in the $lood that can a++ect the clotting process* 'see

Hatient in+ormation: )he antiphospholipid s-ndrome '=e-ond the =asics*H*

& (@ )=@ L)

)he signs and s-mptoms o+ &() ma- $e caused $- a clot, or ma- $e related to another

condition. @maging studies are needed to determine i+ a clot is present.

&eep !ein throm$osis J lassic s-mptoms o+ &() include s"elling, pain, "armth, and redness

in the in!ol!ed leg.

uper+icial phle$itis J uper+icial phle$itis '* causes pain, tenderness, +irmness, and/orredness in a !ein due to in+lammation, in+ection, and/or a $lood clot 'throm$us*. @t is most

commonl- seen in the inner part o+ the lo"er legs.

uper+icial phle$itis di++ers +rom a deep !ein throm$osis $ecause the !eins that are a++ected are

near the sur+ace o+ the skin. -mptoms o+ t-picall- de!elop o!er hours to da-s and resol!e inda-s to "eeks. )he area ma- continue to $e +irm +or se!eral "eeks to months. )reatment usuall-

includes "arm or cool compresses, ele!ation o+ the leg, a nonsteroidal antiin+lammator- agent

'A@&* such as i$upro+en 'Ad!il, otrin*, or anticoagulation. @n most people "ith , there isa lo" risk o+ de!eloping a pulmonar- em$olism, so anticoagulation is not usuall- needed.

& (@ )=@ &@AM@

@+ the patientIs histor-, s-mptoms, and ph-sical e;am suggest a &(), tests are needed to con+irm

this. )ests to diagnose &() ma- include compression ultrasonograph-, contrast !enograph-,magnetic resonance imaging '>@*, computed tomograph- ') scan*, and/or a $lood test called

&dimer.

@+ a person "ith a &() also has signs or s-mptoms o+ a pulmonar- em$olus, additional testing

"ill $e needed. 'ee Hatient in+ormation: ulmonar- em$olism '=e-ond the =asics*H.*

&dimer J &dimer is a su$stance in the $lood that is o+ten increased in people "ith &() or. &dimer testing is sometimes use+ul +or patients "ith a suspected &() or . @+ the &dimer

test is negati!e and the patient has a lo" risk o+ &() or $ased upon his/her histor- and

ph-sical e;amination, &() or are unlikel- and +urther diagnostic testing ma- not $e needed.

ompression ultrasonograph- J ompression ultrasonograph- uses sound "a!es to generate pictures o+ the structures inside the leg. ?or this t-pe o+ e;am, a person lies on his/her $ack and

then stomach as an ultrasound "and is applied to the leg. @n most circumstances, compression

ultrasonograph- is the test o+ choice +or patients "ith suspected &().

ontrast !enograph- J &uring contrast !enograph-, a catheter is threaded into a !ein and a d-e

is inKected. )his allo"s the clinician to see the !ein "ith ;ra-. (enograph- is generall- reser!ed

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+or situations in "hich ultrasound cannot $e done, "hen other tests ha!e not $een help+ul, or

"hen other tests are negati!e $ut the clinician +eels strongl- that a !enous throm$osis is present.

agnetic resonance imaging '>@* J >@ uses a strong magnet to produce detailed pictures o+ the inside o+ the $od-. >@ is as accurate as contrast !enograph-. >@ is e;pensi!e, and its use

ma- $e limited to situations in "hich contrast !enograph- cannot $e per+ormed, such as in patients "ith poor kidne- +unction, during pregnanc-, or $ecause o+ allerg- to the d-e reuired in

contrast !enograph-.

?inding the cause o+ !enous throm$osis J A+ter determining that &() or is present, the

healthcare pro!ider "ill "ant to kno" "hat caused it. @n man- cases, there are o$!ious risk

+actors such as recent surger- or immo$ilit-. 'ee IAcuired throm$ophiliaI a$o!e.* @n othercases, the clinician ma- test +or the presence o+ an inherited +orm o+ throm$ophilia or +or another

medical condition associated "ith an increased risk +or !enous throm$osis. 'ee I@nherited

throm$ophiliaI a$o!e.*

ersons "ith some acuired or inherited a$normalities ma- reuire additional treatment or pre!ention measures to reduce the risk o+ another throm$osis. ome e;perts recommend that the

+amil- mem$ers o+ a person "ith an inherited throm$ophilia $e screened +or the inherited

condition i+ this in+ormation "ould a++ect their care as "ell, although this issue is contro!ersial.

@t is important that the healthcare pro!ider discusses the pros and cons o+ screening +or aninherited throm$ophilia "ith the patient $e+ore this testing is done.

& (@ )=@ )>A))

)he treatment o+ &() and are similar. @n &(), the main goal o+ treatment is to pre!ent a .

ther goals o+ treatment include pre!enting the clot +rom $ecoming larger, pre!enting ne" $lood

clots +rom +orming, and pre!enting longterm complications o+ or &().

)he primar- treatment +or !enous throm$osis is anticoagulation. ther a!aila$le treatments,

"hich ma- $e used in speci+ic situations, include throm$ol-tic therap- or placing a +ilter in a

maKor $lood !essel 'the in+erior !ena ca!a*.

Anticoagulation J Anticoagulants are medications that are commonl- called H$lood thinnersH.

)hese medications do not actuall- thin the $lood, $ut rather helps to pre!ent ne" $lood clots

+rom +orming. atients "ith !enous throm$osis are usuall- treated +irst "ith an inKecta$le

anticoagulant. )here are se!eral such anticoagulants a!aila$le, including:

Un+ractionated heparin, o+ten gi!en into a !ein 'intra!enous*

o" molecular "eight heparin 'eno;aparin/o!eno;, dalteparin/?ragmin, or tinNaparin/@nnohep*

?ondaparinu; 'Ari;tra*

)hese agents can all $e inKected under the skin 'ie, su$cutaneous inKection* $- the patient, a

+amil- mem$er, or a home health nurse. )his allo"s selected patients to $e treated at home.

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)hrom$ol-tic therap- J @n some cases, a healthcare pro!ider "ill recommend an intra!enous

medicine to dissol!e $lood clots. )his is called throm$ol-tic therap-. )his therap- is reser!ed +or

patients "ho ha!e serious complications related to or &(), and "ho ha!e a lo" risk o+serious $leeding as a side e++ect o+ the therap-. )he response to throm$ol-tic therap- is $est

"hen there is a short time $et"een the diagnosis o+ &()/ and the start o+ throm$ol-tic

therap-.

@n+erior !ena ca!a +ilter J An in+erior !ena ca!a '@(* +ilter is a de!ice that $locks thecirculation o+ clots in the $loodstream. @t is placed in the in+erior !ena ca!a 'the large !ein

leading +rom the lo"er $od- to the heart*. )he @( +ilter t-picall- is inserted through a small

incision in a neck !ein "ith the use o+ a local anesthetic and takes 20 to 30 minutes to per+orm.An @( +ilter is o+ten recommended in patients "ith !enous throm$oem$olism "ho cannot use

anticoagulants $ecause o+ a !er- high $leeding risk.

Use o+ an @( +ilter ma- $e recommended in patients "ho de!elop recurrent throm$oem$olism

despite anticoagulation, and in patients "ith pulmonar- pro$lems due to chronic recurrent

em$olism, although this is contro!ersial. @n the long term, @( +ilters can increase the risk o+de!eloping $lood clots.

& (@ )=@ >()@

urgical patients J ertain high risk patients undergoing surger- 'especiall- $one or Kointsurger- and cancer surger-* ma- $e gi!en anticoagulants to decrease the risk o+ $lood clots.

Anticoagulants ma- also $e gi!en to "omen at high risk +or !enous throm$osis during and a+ter

pregnanc-.

@n surgical patients "ith a moderate to lo" risk o+ $lood clots, other pre!enti!e measures ma- $e

used. ?or e;ample, some surgical patients are +itted "ith in+lata$le compression de!ices that are"orn around the legs during and immediatel- a+ter surger- and periodicall- +ill "ith air. )hese

de!ices appl- gentle pressure to impro!e circulation and help pre!ent clots.

Mraduated compression stockings ma- also $e recommendedC these stockings appl- pressure tothe lo"er legs, "ith the greatest pressure at the ankle. )he pressure graduall- decreases up to the

knee. ?or all patients, "alking as soon as possi$le a+ter surger- can decrease the risk o+ a $lood

clot.

;tended tra!el J rolonged tra!el appears to con+er a t"o to +our+old increase in risk o+!enous throm$oem$olism '()* 2. )here are a +e" tips that ma- $e o+ $ene+it during e;tended

tra!el 'ta$le 1*.

@A >AU)@ ?> @)< & (@ )=@

econd throm$osis J atients $eing treated +or !enous throm$osis are at an increased risk +orde!eloping another $lood clot, although this risk is signi+icantl- smaller "hen an anticoagulant is

used. )he patient should "atch +or ne" leg pain, s"elling, and/or redness. @+ these s-mptoms

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occur, the patient should speak to his/her healthcare pro!ider or seek medical attention as soon as

possi$le.

ther s-mptoms ma- indicate that a clot in the leg has $roken o++ and tra!eled to the lung,causing a pulmonar- em$olism. )hese ma- include:

e" chest pain "ith di++icult- $reathing

A rapid heart rate and/or a +eeling o+ passing out

)his complication ma- $e li+ethreatening and reuires immediate attention. mergenc-

medical ser!ices are a!aila$le in most areas o+ the United tates $- calling 911.

=leeding J Anticoagulants such as heparin and "ar+arin can ha!e serious side e++ects andshould $e taken e$actly as directed. @+ a dose is +orgotten, the patient should call his/her pro!ider

or clinic +or ad!ice. )he dose should not $e changed to make up +or missed doses, unless the

pro!ider or clinic directs the patient to do so. atients should immediatel- report to the pharmacist or ph-sician i+ the pill or ta$let looks di++erent +rom the pre!ious $ottle. ther

precautions are necessar- "hen taking "ar+arin, and are outlined in a separate topic re!ie". 'ee

Hatient in+ormation: ar+arin 'oumadin* '=e-ond the =asics*H.*

atients ma- $leed easil- "hile taking anticoagulants. =leeding ma- de!elop in man- areas,such as the nose or gums, e;cessi!e menstrual $leeding, $leeding in the urine or +eces, $leeding

or e;cessi!e $ruising in the skin, as "ell as !omiting material that is $right red or dark $ro"n

like co++ee grounds. @n some cases, $leeding can de!elop inside the $od- and not $e noticedimmediatel-. =leeding inside the $od- can cause a person to +eel +aint, or ha!e pain in the $ack

or a$domen. A healthcare pro!ider should $e noti+ied immediatel- i+ there is an- sign o+ this

pro$lem. A healthcare pro!ider should also $e noti+ied immediatel- i+ the patient onanticoagulants sustained an inKur- that could lead to $leeding inside the $od-.

ear an alert tag J eople "ho take "ar+arin should "ear a $racelet, necklace, or similar alert

tag at all times. @+ medical treatment is reuired and the person is too ill to e;plain his/her

condition, the tag "ill alert responders a$out the patientIs use o+ "ar+arin and risk o+ e;cessi!e $leeding.

)he alert tag should list the personIs medical conditions, as "ell as the name and phone num$er

o+ an emergenc- contact. ne de!ice, edic Alert, pro!ides a toll+ree num$er that emergenc-

medical "orkers can call to +ind out a personIs medical histor-, list o+ medications, +amil-

emergenc- contact num$ers, and healthcare pro!ider names and num$ers.

>educe the risk o+ $leeding J ome simple modi+ications can limit the risk o+ $leeding:

Use a so+t $ristle tooth$rush

?loss "ith "a;ed +loss rather than un"a;ed +loss

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ha!e "ith an electric raNor rather than a $lade

)ake care "hen using scissors or kni!es

A!oid potentiall- harm+ul acti!ities 'eg, contact sports*

&o not take aspirin or other A@& 'eg, i$upro+en, Ad!il, Ale!e, otrin, uprin* unlessdirected to do so $- a healthcare pro!ider. ther nonprescription pain medications, such as

acetaminophen, ma- $e a sa+e alternati!e.

) M) > @?>A)@

Lour healthcare pro!ider is the $est source o+ in+ormation +or uestions and concerns related to

-our medical pro$lem.

)his article "ill $e updated as needed on our "e$site '""".uptodate.com/patients*. >elated

topics +or patients, as "ell as selected articles "ritten +or healthcare pro+essionals, are alsoa!aila$le. ome o+ the most rele!ant are listed $elo".

atient le!el in+ormation J Up)o&ate o++ers t"o t-pes o+ patient education materials.

)he =asics J )he =asics patient education pieces ans"er the +our or +i!e ke- uestions a patientmight ha!e a$out a gi!en condition. )hese articles are $est +or patients "ho "ant a general

o!er!ie" and "ho pre+er short, eas-toread materials.

atient in+ormation: (aricose !eins and other !ein disease in the legs ')he =asics*

atient in+ormation: &eep !ein throm$osis '$lood clots in the legs* ')he =asics*

atient in+ormation: ta-ing health- "hen -ou tra!el ')he =asics*atient in+ormation: "elling ')he =asics*

atient in+ormation:


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atient in+ormation: ulmonar- em$olism '=e-ond the =asics*

atient in+ormation: )he nephrotic s-ndrome '=e-ond the =asics*

atient in+ormation: )he antiphospholipid s-ndrome '=e-ond the =asics*atient in+ormation: ar+arin 'oumadin* '=e-ond the =asics*

ro+essional le!el in+ormation J ro+essional le!el articles are designed to keep doctors andother health pro+essionals uptodate on the latest medical +indings. )hese articles are thorough,

long, and comple;, and the- contain multiple re+erences to the research on "hich the- are $ased.ro+essional le!el articles are $est +or people "ho are com+orta$le "ith a lot o+ medical

terminolog- and "ho "ant to read the same materials their doctors are reading.

Use o+ anticoagulants during pregnanc- and postpartumApproach to the diagnosis and therap- o+ lo"er e;tremit- deep !ein throm$osis

&eep !ein throm$osis in pregnanc-: pidemiolog-, pathogenesis, and diagnosis

&eep !ein throm$osis and pulmonar- em$olism in pregnanc-: re!ention

&eep !ein throm$osis and pulmonar- em$olism in pregnanc-: )reatment

&iagnosis o+ suspected deep !ein throm$osis o+ the lo"er e;tremit-tiolog-, clinical +eatures, and diagnosis o+ cere$ral !enous throm$osis

!aluation o+ the patient "ith esta$lished !enous throm$osis?i$rinol-tic 'throm$ol-tic* therap- in acute pulmonar- em$olism and lo"er e;tremit- deep !ein

throm$osis

>isk and pre!ention o+ !enous throm$oem$olism in adults "ith cancer lacement o+ !ena ca!a +ilters and their complications

o" molecular "eight heparin +or !enous throm$oem$olic disease

erioperati!e management o+ patients recei!ing anticoagulants

anagement o+ inherited throm$ophilia!er!ie" o+ the causes o+ !enous throm$osis

re!ention o+ !enous throm$oem$olic disease in medical patientsre!ention o+ !enous throm$oem$olic disease in surgical patients)herapeutic use o+ heparin and lo" molecular "eight heparin

)herapeutic use o+ "ar+arin and other !itamin E antagonists

)reatment o+ lo"er e;tremit- deep !ein throm$osis

)he +ollo"ing organiNations also pro!ide relia$le health in+ormation.

ational i$rar- o+ edicine

'""".nlm.nih.go!/medlineplus/healthtopics.html*

ational


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19

page 2

=O)@(: )o in!estigate the time relations $et"een long haul air tra!el and !enousthrom$oem$olism.

&@M: >ecord linkage stud- using the case crosso!er approach.))@M: estern Australia.

A>)@@A): 5408 patients admitted to hospital "ith !enous throm$oem$olism and matched"ith data +or arri!als o+ international +lights during 198199.

>U): )he risk o+ !enous throm$oem$olism is increased +or onl- t"o "eeks a+ter a long

haul +lightC 4% Australian citiNens and 200 nonAustralian citiNens had an episode o+ !enousthrom$oem$olism during this so called haNard period. )he relati!e risk during this period +or

Australian citiNens "as 4.17 '956 con+idence inter!al, 2.94 to 5.40*, "ith 7%6 o+ cases 'n G 35*

attri$uta$le to the preceding +light. A Hhealth- tra!ellerH e++ect "as o$ser!ed, particularl- +orAustralian citiNens.

U@: )he annual risk o+ !enous throm$oem$olism is increased $- 126 i+ one long

haul +light is taken -earl-. )he a!erage risk o+ death +rom +light related !enousthrom$oem$olism is small compared "ith that +rom motor !ehicle crashes and inKuries at "ork.

)he indi!idual risk o+ death +rom +light related !enous throm$oem$olism +or people "ith certain

pree;isting medical conditions is, ho"e!er, likel- to $e greater than the a!erage risk o+ 1 per 2

million +or passengers arri!ing +rom a +light. Airlines and health authorities should continue toad!ise passengers on ho" to minimise risk.
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Documents

Deep Venous Thrombosi