This document summarizes a seminar presentation on deep venous thrombosis (DVT). It defines DVT, discusses its incidence in India compared to Western populations, and outlines Virchow's triad of factors that can lead to DVT - venous stasis, endothelial damage, and hypercoagulability. Diagnostic tests like Doppler ultrasound, MRI, and D-dimer are covered. Treatment options include anticoagulation with heparin or warfarin, thrombolytic therapy, and surgery in some cases. Compression stockings and duration of treatment are also discussed.

1. G.R. MEDICAL COLLEGEG.R. MEDICAL COLLEGE
DEPARTMENT OF SURGERYDEPARTMENT OF SURGERY
SEMINAR PRESENTATIONSEMINAR PRESENTATION
DEEP VENOUS THROMBOSISDEEP VENOUS THROMBOSIS
Guide:Guide: By:By:
Prof. Dr. Achal GuptaProf. Dr. Achal Gupta (M.S., DNB)(M.S., DNB) Dr Nikhil ChopraDr Nikhil Chopra
HODHOD 22ndnd
yryr PG StudentPG Student

2. DefinitionDefinition
• Deep vein thrombosis is the formation of a bloodDeep vein thrombosis is the formation of a blood
clot in one of the deep veins of the body, usually in theclot in one of the deep veins of the body, usually in the
legleg
• IncidenceIncidence: Indian population< Western population: Indian population< Western population
• Around 2.7 per 1000 person-days of hospital stay with 50%Around 2.7 per 1000 person-days of hospital stay with 50%
hospitalised population at risk.hospitalised population at risk.
• Ref: Sharma et al, Indian J med Dec 2009Ref: Sharma et al, Indian J med Dec 2009

3. ETIOLOGYETIOLOGY
 DVT usually originates in the lower extremity venous levelDVT usually originates in the lower extremity venous level
,starting at the calf vein level and progressing proximally to,starting at the calf vein level and progressing proximally to
involve popliteal ,femoral ,or iliac system.involve popliteal ,femoral ,or iliac system.
 80 -90 % pulmonary emboli originates here .80 -90 % pulmonary emboli originates here .

4. Virchow triadVirchow triad
 Virchow described a triad of factors ofVirchow described a triad of factors of
a.a. Venous stasis,Venous stasis,
b.b. Endothelial damage, andEndothelial damage, and
c.c. Hypercoagulable stateHypercoagulable state

5. Venous stasisVenous stasis
 Prolonged bed rest (4 days or more)Prolonged bed rest (4 days or more)
 A cast on the legA cast on the leg
 Limb paralysis from stroke or spinal cord injuryLimb paralysis from stroke or spinal cord injury
 extended travel in a vehicleextended travel in a vehicle
HypercoagulabilityHypercoagulability
 Surgery and traumaSurgery and trauma
 MalignancyMalignancy
 Increased estrogenIncreased estrogen

6. Disorders of coagulationDisorders of coagulation
InheritedInherited
Deficiencies ofDeficiencies of
1.1. Protein ‘S,Protein ‘S,
2.2. Protein ‘C,’ andProtein ‘C,’ and
3.3. Antithrombin IIIAntithrombin III
AcquiredAcquired
a.a. Nephrotic syndromeNephrotic syndrome
b.b. Antiphospholipid antibodiesAntiphospholipid antibodies
c.c. Inflammatory processes such as SLE, Sickle cell disease andInflammatory processes such as SLE, Sickle cell disease and
IBDIBD

7. Presentation and PhysicalPresentation and Physical
ExaminationExamination
 Calf pain/tendernessCalf pain/tenderness
 Swelling with pitting oedemaSwelling with pitting oedema
 Increased skin temperatureIncreased skin temperature
 Superficial venous dilatationSuperficial venous dilatation
 Assess limb perfusion.Assess limb perfusion.
 Detect acute arthritis/joint pathology.Detect acute arthritis/joint pathology.
 Neurologic evaluationNeurologic evaluation
 Homans'’ signHomans'’ sign

8. Wells Clinical Prediction GuideWells Clinical Prediction Guide
 Active cancer (treatment ongoing, or within 6 monthsActive cancer (treatment ongoing, or within 6 months
or palliative) = +1or palliative) = +1
 Paralysis or recent immobilization = +1Paralysis or recent immobilization = +1
 Recently bedridden for >3 days or major surgery <4Recently bedridden for >3 days or major surgery <4
weeks = +1weeks = +1

9.  Localized tenderness along the distribution of the deepLocalized tenderness along the distribution of the deep
venous system = +1venous system = +1
 Entire leg swelling = +1Entire leg swelling = +1
 Calf swelling >3 cm compared to the asymptomatic legCalf swelling >3 cm compared to the asymptomatic leg
= +1= +1
 Pitting edema (greater in the symptomatic leg) = +1Pitting edema (greater in the symptomatic leg) = +1
 Collateral superficial veins (nonvaricose) = +1Collateral superficial veins (nonvaricose) = +1
 Alternative diagnosis (as likely or > that of DVT)= -2Alternative diagnosis (as likely or > that of DVT)= -2

10.  Total of Above ScoreTotal of Above Score
High probability: Score 3High probability: Score 3
Moderate probability: Score = 1 or 2Moderate probability: Score = 1 or 2
Low probability: Score 0Low probability: Score 0

11. Diagnostic StudiesDiagnostic Studies
 Clinical examination alone is able to confirm only 20-Clinical examination alone is able to confirm only 20-
30% of cases of DVT30% of cases of DVT
 Blood TestsBlood Tests
 the D-dimerthe D-dimer
 INR.INR.

12. D-dimerD-dimer
 D-dimer is a specific degradation product of cross-linked fibrin.D-dimer is a specific degradation product of cross-linked fibrin.
Because concurrent production and breakdown of clotBecause concurrent production and breakdown of clot
characterize thrombosis, patients with thromboembolic diseasecharacterize thrombosis, patients with thromboembolic disease
have elevated levels of D-dimerhave elevated levels of D-dimer
 Three major approaches for measuring D-dimerThree major approaches for measuring D-dimer
 ELISAELISA
 Latex agglutinationLatex agglutination
 Blood agglutination testBlood agglutination test

13.  False-positive D-dimers occur in patients withFalse-positive D-dimers occur in patients with
 recent (within 10 days) surgery or trauma,recent (within 10 days) surgery or trauma,
 recent myocardial infarction or stroke,recent myocardial infarction or stroke,
 acute infection,acute infection,
 disseminated intravascular coagulation,disseminated intravascular coagulation,
 pregnancy or recent delivery,pregnancy or recent delivery,
 active collagen vascular disease, or metastatic canceractive collagen vascular disease, or metastatic cancer

14. Imaging StudiesImaging Studies
 InvasiveInvasive
 venography,venography,
 radiolabeled fibrinogen and.radiolabeled fibrinogen and.
 NoninvasiveNoninvasive
 ultrasound,ultrasound,
 MRI techniquesMRI techniques

15. VenographyVenography
 Gold standard” modality for the diagnosis of DVTGold standard” modality for the diagnosis of DVT
Nuclear Medicine StudiesNuclear Medicine Studies
 Can distinguish new clot fromCan distinguish new clot from an old clotan old clot

16. UltrasonographyUltrasonography
 Color-flow Duplex scanning is the imaging test of choice forColor-flow Duplex scanning is the imaging test of choice for
patients with suspected DVTpatients with suspected DVT
 inexpensive,inexpensive,
 noninvasive,noninvasive,
 widely availablewidely available
 Ultrasound can also distinguish other causes of leg swelling, suchUltrasound can also distinguish other causes of leg swelling, such
as tumor, popliteal cyst, abscess, aneurysm, or hematoma. as tumor, popliteal cyst, abscess, aneurysm, or hematoma.

17. Clinical limitationsClinical limitations
 expensiveexpensive
 reader dependentreader dependent
 Duplex scans are less likely to detect non-occluding thrombi.Duplex scans are less likely to detect non-occluding thrombi.
 During the second half of pregnancy, ultrasound becomes lessDuring the second half of pregnancy, ultrasound becomes less
specific, because the gravid uterus compresses the inferior venaspecific, because the gravid uterus compresses the inferior vena
cava, thereby changing Doppler flow in the lower extremitiescava, thereby changing Doppler flow in the lower extremities

18. Magnetic Resonance ImagingMagnetic Resonance Imaging
 It detects leg, pelvis, and pulmonary thrombi and is 97%It detects leg, pelvis, and pulmonary thrombi and is 97%
sensitive and 95% specific for DVT.sensitive and 95% specific for DVT.
 It distinguishes a mature from an immature clot.It distinguishes a mature from an immature clot.
 MRI is safe in all stages of pregnancy.MRI is safe in all stages of pregnancy.

19. DIFFERENTIAL DIAGNOSISDIFFERENTIAL DIAGNOSIS
CellulitisCellulitis
ThrombophlebitisThrombophlebitis
ArthritisArthritis
Peripheral edemaPeripheral edema
LymphangitisLymphangitis
Extrinsic compression of iliacExtrinsic compression of iliac
veinvein
LymphedemaLymphedema
Muscle or soft tissue injuryMuscle or soft tissue injury
Neurogenic painNeurogenic pain
Postphlebitic syndromePostphlebitic syndrome
 Prolonged immobilization orProlonged immobilization or
limb paralysislimb paralysis
Ruptured Baker cystRuptured Baker cyst
Stress fractures or other bonyStress fractures or other bony
lesionslesions
Superficial thrombophlebitisSuperficial thrombophlebitis
Varicose veinsVaricose veins

20. MANAGEMENTMANAGEMENT
RISK DOPPLER FINDINGS DIAGNOSIS
High/Moderate Positive DVT
Low Negative DVT ruled out
High Negative +/-
Low Positive +/-

21. EMERGENCY DEPARTMANT CAREEMERGENCY DEPARTMANT CARE
 Objectives:Objectives:
1.1. prevent pulmonary embolism,prevent pulmonary embolism,
2.2. reduce morbidity, andreduce morbidity, and
3.3. prevent or minimize the risk of developing the postphlebiticprevent or minimize the risk of developing the postphlebitic
syndrome.syndrome.
Treatment options:Treatment options:
 AnticoagulationAnticoagulation
 Thrombolytic therapyThrombolytic therapy
 SurgerySurgery
 Compression stockingsCompression stockings

22. AnticoagulationAnticoagulation
 Heparin prevents thrombus extension.Heparin prevents thrombus extension.
 Dose: Bolus-80U/kg f/b 18U/kg/hrDose: Bolus-80U/kg f/b 18U/kg/hr
 Monitoring: aPTTMonitoring: aPTT
 Target: 1.5-2.3Target: 1.5-2.3

23. Advantages of Low-Molecular-Weight
Heparin Over
Standard Unfractionated Heparin
 Superior bioavailability
 Superior or equivalent safety and efficacy
 Subcutaneous once- or twice-daily dosing
 No laboratory monitoring*
 Less phlebotomy (no monitoring/no intravenous line)
 Less thrombocytopenia
At the present time, 3 LMWH preparations,At the present time, 3 LMWH preparations,
 Enoxaparin,Enoxaparin,
 Dalteparin, andDalteparin, and
 ArdeparinArdeparin

24. WarfarinWarfarin
 Interferes with hepatic synthesis of vitamin K-dependentInterferes with hepatic synthesis of vitamin K-dependent
coagulation factorscoagulation factors
 Monitoring: INRMonitoring: INR
 caution in active tuberculosis or diabetes; patients with protein Ccaution in active tuberculosis or diabetes; patients with protein C
or S deficiencyor S deficiency

25. Thrombolytic therapy for DVTThrombolytic therapy for DVT
 Advantages:Advantages:
 prompt resolution of symptoms,prompt resolution of symptoms,
 prevention of pulmonary embolism,prevention of pulmonary embolism,
 restoration of normal venous circulation,restoration of normal venous circulation,
 preservation of venous valvular function,preservation of venous valvular function,
 prevention of postphlebitic syndromeprevention of postphlebitic syndrome
Thrombolytic therapy does not preventThrombolytic therapy does not prevent
 clot propagation,clot propagation,
 rethrombosis, orrethrombosis, or
 subsequent embolization.subsequent embolization.

26. Surgery for DVTSurgery for DVT
 IndicationsIndications
a.a. when anticoagulant therapy is ineffectivewhen anticoagulant therapy is ineffective
b.b. unsafe,unsafe,
c.c. contraindicated.contraindicated.

27.  These pulmonary emboli removed at autopsy look likeThese pulmonary emboli removed at autopsy look like
casts of the deep veins of the leg where they originated.casts of the deep veins of the leg where they originated.


28. This patient underwent a thrombectomy. The thrombus has beenThis patient underwent a thrombectomy. The thrombus has been
laid over the approximate location in the leg veins where itlaid over the approximate location in the leg veins where it
developed.developed.

29. Filters for DVTFilters for DVT
 Indications:Indications:
a.a. Pulmonary embolismPulmonary embolism
b.b. Recurrent pulmonary embolism despite adequate anticoagulationRecurrent pulmonary embolism despite adequate anticoagulation
 Controversial indications:Controversial indications:
a.a. DVTDVT
b.b. In patients with pre-existing pulmonary hypertensionIn patients with pre-existing pulmonary hypertension
c.c. Free floating thrombusFree floating thrombus
d.d. Failure of existing filter deviceFailure of existing filter device
e.e. Post pulmonary embolectomyPost pulmonary embolectomy

31. Compression stockings (routinelyCompression stockings (routinely
recommendedrecommended

32. Further Inpatient CareFurther Inpatient Care
 Most patients with confirmed proximal vein DVT may be treatedMost patients with confirmed proximal vein DVT may be treated
safely on an outpatient basis. Exclusion criteria for outpatientsafely on an outpatient basis. Exclusion criteria for outpatient
management are as follows:management are as follows:
a.a. Suspected or proven concomitant pulmonary embolismSuspected or proven concomitant pulmonary embolism
b.b. Significant cardiovascular or pulmonary comorbiditySignificant cardiovascular or pulmonary comorbidity
c.c. Morbid obesityMorbid obesity
d.d. Renal failureRenal failure
e.e. Unavailable or unable to arrange close follow-up careUnavailable or unable to arrange close follow-up care

33. Duration of anticoagulation in patients with deepDuration of anticoagulation in patients with deep
vein thrombosisvein thrombosis
a.a. Transient cause and no other risk factors: 3 monthsTransient cause and no other risk factors: 3 months
b.b. Idiopathic: 3-6 monthsIdiopathic: 3-6 months
c.c. Ongoing risk: 6 -12 monthsOngoing risk: 6 -12 months
d.d. Recurrent pulmonary embolism/DVT: 6-12 monthsRecurrent pulmonary embolism/DVT: 6-12 months
e.e. Patients with high risk of recurrent thrombosis exceeding riskPatients with high risk of recurrent thrombosis exceeding risk
of anticoagulation: indefinite duration (subject to review)of anticoagulation: indefinite duration (subject to review)

34. ComplicationsComplications
 Acute pulmonary embolismAcute pulmonary embolism
 Hemorrhagic complicationsHemorrhagic complications
 Chronic venous insufficiencyChronic venous insufficiency

35. Prognosis:Prognosis:
 All patients with proximal vein DVT are at long-term risk of developingAll patients with proximal vein DVT are at long-term risk of developing
chronic venous insufficiency.chronic venous insufficiency.
 Proximal DVT---- 20% PE --10% mortalityProximal DVT---- 20% PE --10% mortality
 DVT confined to the calf: no PEDVT confined to the calf: no PE

36. Patient Education:Patient Education:
 Advise women taking estrogen of the risks andAdvise women taking estrogen of the risks and
common symptoms of thromboembolic disease.common symptoms of thromboembolic disease.
 Discourage prolonged immobility, particularly on planeDiscourage prolonged immobility, particularly on plane
rides and long car tripsrides and long car trips

37. DVT PROPHYLAXIS IN SURGICALDVT PROPHYLAXIS IN SURGICAL
PATIENTSPATIENTS
 A VTE risk assessment should follow the following steps:A VTE risk assessment should follow the following steps:
 Step 1Step 1 Assess the patient’s baseline risk of VTE, taking intoAssess the patient’s baseline risk of VTE, taking into
account inherited and acquired pt factorsaccount inherited and acquired pt factors
 Step 2Step 2 Assess the patient’s additional risk of VTE, takingAssess the patient’s additional risk of VTE, taking
account of the reasons for hospitalisation.account of the reasons for hospitalisation.
 Step 3Step 3 Assess the patient’s risk of bleeding.Assess the patient’s risk of bleeding.
 Step 4Step 4 Formulate an overall risk assessment (with considerationFormulate an overall risk assessment (with consideration
of VTE risk and bleeding risk).of VTE risk and bleeding risk).
 Step 5Step 5 Select appropriate methods of thromboprophylaxisSelect appropriate methods of thromboprophylaxis
based on the risk assessment.based on the risk assessment.

38.  Thromboprophylaxis is initiated depending on combination ofThromboprophylaxis is initiated depending on combination of
multiple risk factors:multiple risk factors:
 Individual pt risk factorsIndividual pt risk factors
 Risk factors related to acute medical illnessRisk factors related to acute medical illness
 Risk related to surgical procedureRisk related to surgical procedure

39.  Individual patient risk factorsIndividual patient risk factors::
 ageage
 pregnancy and the puerperiumpregnancy and the puerperium
 active or occult malignancyactive or occult malignancy
 previous VTEprevious VTE
 varicose veinsvaricose veins
 marked obesitymarked obesity
 prolonged severe immobilityprolonged severe immobility
 use of oestrogen-containing hormone replacement therapy oruse of oestrogen-containing hormone replacement therapy or
oral contraceptivesoral contraceptives
 •• inherited or acquired thrombophiliainherited or acquired thrombophilia

40. Risks related to an acute medical
illness:
a. acute or acute on chronic chest infection
b. heart failure
c. myocardial infarction
d. stroke with immobility
e. some forms of cancer chemotherapy
f. acute inflammatory bowel disease
Risks related to an injury or surgical
procedure:
All surgical procedures but especially abdominal,
pelvic, thoracic or orthopaedic surgical
procedures

41. BLEEDING RISKBLEEDING RISK
 recent central nervous system bleedingrecent central nervous system bleeding
 intracranial or spinal lesion at high risk for bleedingintracranial or spinal lesion at high risk for bleeding
 current active major bleeding, defined as requiring at least twocurrent active major bleeding, defined as requiring at least two
units of blood or blood products to be transfused in 24 hoursunits of blood or blood products to be transfused in 24 hours
 current chronic, clinically significant and measurable bleedingcurrent chronic, clinically significant and measurable bleeding
over 48 hoursover 48 hours

42. GuidelinesGuidelines
 Identification of risk:Identification of risk:
RISK SURGERY AGE (yrs) RISK
FACTORS
Low <30min <40 Nil
Moderate <30 min
<30 min
>30 min
--
40-60
<40
+nt
Nil
Nil
High <30 min
>30 min
>60
> 40
+nt
+nt
Highest >30 min 60 +nt plus
history of
VTE

43. PROPHYLAXISPROPHYLAXIS
Non pharmacological methodsNon pharmacological methods::
a.a. Early mobilisationEarly mobilisation
b.b. Elastic stockingsElastic stockings
c.c. Pneumatic compression devicesPneumatic compression devices
Pharmacological methodsPharmacological methods::
a.a. AspirinAspirin
b.b. Unfractionated heparinUnfractionated heparin
c.c. LMWHLMWH
d.d. Oral anticoagulantsOral anticoagulants

44. RISK PROPHYLAXIS
Low Nil
Moderate Compression stockings
Pneumatic compression
UFH
Enoxaparin
High Compression stockings
Pneumatic compression
UFH
Enoxaparin