2. VENOUS THROMBOEMBOLISM Composite
term for DVT &PE
The presence of thrombus with in deep veins
is termed as deep vein thrombosis
It is a life threatening condition that may lead
to sudden death in the short term or long
term morbidity due to the development of
post thrombotic limb and venous ulceration
3. 1846 virchow recognised association of
thrombus in leg and PE.
1916 J McLean ,a medical student discovered
heparin
1937 Heparin introduced to clinical practice.
Last 25 years significant progress made in our
understanding of DVT.
4. CLASSIFICATION :
PROXIMAL DVT :thrombus formed in veins
above the knee jt (femoral, iliac, popliteal)
DISTAL DVT : those formed below the knee jt
(calf veins)
5. Venous thrombosis are difficult
to recognize clinically. The
documented cases probably
represent only tip of the Ice
Berg.
SILENT KILLER
6. M:F 1.2:1
Age more than 40 years.
VT occur in more than 50% of patient’s having
orthopaedic surgical procedures.
10 to 20% of patient with idiopathic DVT have or
develop cancer.
1/3rd
to 1/4th
patient having proximal DVT may
develop PE.
About 10% of hospital deaths attributable to PE
(from DVT)
7. Calf vein - most common
Ilio femoral - most symtomatic
IVC - most lethal
8. Blood clots occurring in people sitting at the
computer for prolonged periods of time.
AIR TRAVEL AND DVT
Up to 1 out of 10 air line passengers develop small
asymptomatic blood clots.
Due to hypoxia and reduced cabin pressure.
VT occurs in patients regularly without any damaged
to the blood vessels.
9. VTE Risk Stratification
Patient Factors: Clinical
Age
Previous VTE
Malignancy
Advancing age
Obesity
Prolonged immobility
Trauma
Surgery (THR, TKR, HFS)
Pregnancy/ postpartum
Indwelling central venous catheter
Thrombophilia
Deficiency of anti-thrombin III
Protein C or S
Contd...
11. Pregnancy and postpartum period.
Immoblisation longer than 3 days
Major surgery in previous 4weeks
Long air or car trips >4hrs in previous 4 weeks
13. 1. Propagation
2. Embolization
3. Dissolution
4. Organization & recanalisation
ORGIN
DVT usually originates from veins of calf
around the valve cusps or with in soleal
plexus
A minority of cases occurs directly in ilio
femoral veins
14. In practical terms the development of VT is
best understood as activation of coagulation in
areas of reduced blood flow.
Majority of calf vein thrombus dissolve
completely.
Only 20% progress proximally.
Propagation occurs before embolisation.
15. The process of adherence and organisation of
venous thrombus does not begin until 5 to 10
days after thrombus formation.
This non adherent thrombus may propagate or
embolise.
Propagation or organisation of venous
thrombus destruction of valves & varying
degree of venous outflow obstruction
chronic venous insufficiency.
16. 1. Fatal PE
2. Non-fatal PE
3. Post-thrombotic syndrome
Rate of fatal PE in gen population >65yrs is .
003%
In ortho pts (THR,TKR) it is 0.3%
10 fold increase in risk of having fatal PE
17. Consequence of recanalisation of major
venous thrombus
Due to incompetence of valves
Long term morbidity
Causes chronic edema &venous ulcers
18. Swelling/edema
most specific sign
unilateral
Leg pain (50%)
non specific
Redness/erythema
over the thrombus
Tenderness(75%)
calf or along the involved veins
does not correlate size, site, extent
Low grade pyrexia
Signs and symptoms of PE
19. Pain or discomfort in leg on forceful dorsiflexion
of foot with knee straight
Time honoured sign
Present only in 10% of confirmed DVT
Highly non-specific
Present in 50%of cases with out DVT
Misleading sign
No longer used
20. Pts with superficial thrombophlebitis with out
coexisting varicose veins & with no other
etiology (IV Catheter) are at high risk of having
DVT (40%)
Pts with ST extending to sapheno-femoral jn
are at high risk of associated DVT
21. Painful blue inflammation
PHLEGMASIA ALBA DOLENS
Painful white inflammation
Massive IVF thrombus with arterial spasm
22. In approximately 70% of patients with clinically suspected
DVT, alternate diagnoses are ultimately found as follows:
Arthritis
Cellulitis, lymphangitis
Hematoma
Lymphedema
Muscle or soft tissue injury
Neurogenic pain
Postphlebitic syndrome
Prolonged immobilization or limb paralysis
Ruptured Baker cyst
Stress fractures or other bony lesions
Superficial thrombophlebitis
Varicose veins
23. D-DIMER STUDY
D-dimer fibrin fragments are present in fresh fibrin clots and
fibrin dehydration products of cross linked fibrin.
Monoclonal antibodies specific to D-dimer fragment are used to
differentiate fibrin specific clots from noncrosslinked fibrin and
from fibrinogen. These specific attributes of the D-dimer
antibodies account for their high sensitivity for venous
thromboembolism.
Elevated in any medical condition where clots form.
Rised in trauma, recent surgery, haemorrhage, cancer and
sepsis.
It has high sensitivity and low specificity for VTE.
Levels elevated in DVT for seven days.
After clot organisation and adherence the levels decrease.
24. Current evidence strongly supports the use of a D-
dimer assay in the clinical algorithm of suspected
DVT.
A negative D-dimer assay R/O DVT in patients
with low-to-moderate risk (Wells DVT score <2).
All patients with positive D-dimer assay and all
patient with a moderate-to-high risk of DVT ( Wells
DVT score >=2) require a diagnostic study.
25. Protein S, protein C, anticromin III, factor V Leyden,
prothrombin 20210A mutation, antiphospholipid
antibodies and homocysteine levels can be measured.
investigations for these abnormalities are primarily
indicated when DVT is diagnosed in patients younger that
35 years or when venous thrombosis is detected in
unusual sites.
26. CONTRAST VENOGRAPHY
Gold standard for DVT.
Used when other test are inconclusive.
It is either contra indicated or non diagnostic in as many as 20-25%
of patients.
Drawbacks : Allergic reactions, contrast induced DVT, technical
problems, inter observer variability and lack of availability.
It is replaced by non invasive studies as initial diagnostic test.
27. Combination of real – time ultrasonographic
imaging with Doppler flow studies.
Sensitivity for proximal DVT is 97% for calf
veins is 73%.
Overall specificity is 95%.
Helpful to differentiate from haematoma,
baker cyst, abscess and other causes of leg
pain and edema.
28. Primary disadvantage : Inherent inaccuracy in
diagnosis of calf vein thrombosis.
Those proximal to the inguinal ligament are also
difficult to visualize. Non occluding thrombi may be
difficult to detect.
Not able to differentiate to old and new clots in
patients with acute recurrent DVT.
Depends on experience of radiologist
29. Based on recording changes in blood volume of an
extremity, which are directly related to venous outflow.
Sensitive and specific for proximal vein thrombosis.
Cannot differentiate between thrombotic occlusion and
extra vascular compression of the vein.
Insensitive for calf vein thrombosis, non-occluding
proximal DVT and ileofemoral DVT.
30. Increasingly used.
Accuracy approaches to that of contrast venograghy.
Diagnostic test of choice for suspected iliac vein & IVC
thrombosis.
2nd
&3rd
trimester of pregnancy (gravid uterus alters
doppler flow characteristics).
In suspected calf vein thrombosis it is more sensitive
than other non invasive study.
Expense, lack of general availability and technical issues
limit its use.
31. Used for pelvis vein thrombosis.
NUCLEAR MEDICINE IMAGING STUDIES
I125
labeled fibrinogen.
Takes longer than 24 hrs.
No longer used.
32. PRIMARY OBJECTIVES
1. To prevent PE.
2. Reduce morbidity.
3. Prevent or minimize risk of developing the postphletic
syndrome.
SURGICAL TREATMENT
1. Indicated when anticoagulant therapy is ineffective, unsafe or
contraindicated.
2. Major surgical procedures : clot removal and partial
interruption of IVC to prevent PE.
33. To restore venous patency and valvular function.
Alone it is not indicated because rethrombosis is frequent.
Heparin therapy is a necessary adjunct.
Best reserved for patients with massive IF vein thrombosis
when limb viability is at risk.
FILTERS FOR DVT
First suggested by Trousseau in 1868.
Today introducing intracaval devices percutaneosly and floating
them into position with fluoroscopy is the procedure of choice
for filter placement.
34. Severe hemorrhage complications of
anticoagulant therapy.
Absolute contra indications to anticoagulation.
Failure of anticoagulation such us new or
recurrent VTE or PE.
35. Bed rest
Affected limb is elevated above the level of heart.
Anticoagulant prevent thrombus propagation and
allow the endogenous lytic system to operate
Pain relief.
36. Initial bolus 7500 to 10000 IU followed by
continuous in infusion to 1000 to 1500 IU/hr.
Infusion rate adjusted so that aPTT is approx
twice the control value
Every 6 hrs aPTT monitered till therapeutic
range is reached
Duration :5 days
Discontinue when platelet count <75,000
37. Effective and better than conventional heparin.
Different preparations available.
Administered SC in fixed doses once or twice
daily.
Duration -7 to 14 days
Anticoagulant effect by inhibiting the activated
factor X.
Hemorrhagic complications doesn’t occur
38. LMWHs are individual, distinct compounds
that exhibit unique physical, pharmacokinetic
and pharmacodynamic profiles
LMWHs exhibit distinct non-antithrombin III-
mediated effects, including unique tissue
factor pathway inhibition and von Willebrand
factor release profiles.
39. Currently four LMWH are available.
Enoxaparin
Tinazaparin
Dalteparin
Nadroparin
Only enoxaparin and tinazaparin are
approved by FDA for DVT prophylaxis.
40. To be taken along with heparin for initial 4 to5
days.
Dose adj to maintain prothrombin time at INR
2.0 to3.0
Continued for 3 to6 months for pts with acute
idiopathic DVT
For recurrent DVT/PE low intensity warfarin
continued indefinitely maintaining INR 1.5 to2.0
41. Early administration
a) Prompt resolution of symptoms
b) Accelerate clot lysis
c) Preserve venous valves
d) Decrease the potential for developing post-
phlebitic syndrome
42. Does not prevent clot propagation or
rethrombosis.
Heparin and oral anti coagulant therapy must
follow a course of thrombolysis.
Haemorraghic complications reduced by
regionally administering with flouroscopic
control.
Streptokinase,urokinase,tPA (alteplase)
43. Lepirudin or aragatroban
Used when heparin is contra indicated due to
HIT(heparin induced thombocytopenia)
44. LOW RISK: young pts ,minor illness, surgery
lasting <30 mt with no risk factors
MODERATE RISK: >40yrs with deblitating
illness undergoing major surgery but no risk
factors
HIGH RISK: >40 yrs with serious medical
condition undergoing major surgery with
additional risk factors
45. YES - Overall reduction in DVT and PE is by 40%
to 60%
46. Three pronged approach
Designed to address stasis & coagulation
Usually combination of therapies
I. EARLY MOVT & REHABLITATION
II. MECHANICAL METHODS
lower extremity exercises
graded compression stockings
47. intermittent pneumatic compression devices
CPM
III PHARMACOLOGICAL PROPHYLAXIS
a) ASPIRIN
easy to administer
low cost
few bleeding complications
48. Most commonly used
Takes 36 hrs to start action
Started day before surgery
Low doses are used
LOW MOLECULAR WT HEPARIN
More effective than conventional
Lesser bleeding
49. Low molecular wt heparinoid
For pts with HIT
Fondaparinux
Synthetic pentasaccharide
50. Graduated compression stockings
Exercise
Avoid alcohol &sleeping tablets
HIGH RISK PATIENTS
LMWH ,single dose SC before the flight
51. PAGET VON SCHROTTER DISEASE
Axillary and sub clavian vein thrombosis
Reduced incidence
Thoracic outlet synd &cervical ribs
Thrombolytic therapy is treatment of choice
Since restoring venous patency more important
in upper limb
52. Early - Progression
Pulmonary
embolism Paradoxical
embolism Acute
compartment syndrome venous gangrene
Late - Rec DVT, Post phlebitic syndrome
53. Special group of pts
very high risk for DVT & may reach up to 60 to 80% with
out prophylaxis (THR)
Assymptomatic DVT common in >50% of all patients
PE develop in 10 to 20 %of pts
Even with prophylaxis DVT & PE remains the most
common cause for emergency readmission and
death in joint replacement pts
54. •Pre-op Immobilization (stasis)
•Trigger of tissue factor
reamed products (THR)
tissue debris ,fat activation of
coagulation
• Distortion of Femoral and Poplietal viens
retraction,twisting,manipulation –
damage to vessel wall
•Prolonged post-op Immobilization.
55. THR, TKR
Hip fracture surgery
Spine surgery [ malignancy, neurological deficit]
56. Although thromboprophylaxis is routinely given
to patients who undergo major orthopedic
surgery, it is usually stopped at discharge.
Coagulation cascade remains abnormal upto 4
weeks.
Risk of propagation of the DVT, and PE,
remains active during this period.
Patients undergoing THA TKA or HFS receive
Thromboprophylaxis with LMWH Fondaparinux
or VKA for a minimum of ten days. [can be cont.
for 4 – 5 wks]
57. Not an uncommon condition in clinical practice
DVT OCCURS ONLY IN POST-OP PATIENTS’ IS A MYTH
Awareness is most important for early diagnosis
Prompt treatment can prevent lethal complications
Diagnosis can be made using noninvasive methods
Long term follow up is necessary to identify patients
who develop chronic venous insufficiency.