DVT refers to deep vein thrombosis, or a blood clot in the deep veins usually of the legs. It is a common complication after orthopedic surgeries due to immobility and direct manipulation of veins. Diagnosis involves tests like ultrasound, CT, or MRI. Risk factors include immobilization, endothelial injury, and hypercoagulability. Treatment involves anticoagulation drugs or thrombolysis to prevent pulmonary embolism. Prophylaxis includes early mobilization, compression stockings, and anticoagulants. Combined prophylaxis is most effective at preventing DVT and PE after orthopedic surgeries.

1. DVT
(DEEP VENOUS THROMBOSIS)

2. Introduction
• Venous thromboembolism (VTE) - one of
the commonest complications of lower
limb surgery.
• includes 2 different clinical entities: deep
vein thrombosis (DVT) and pulmonary
embolism (PE)
• Orthopaedic patients - high risk due to
immobility and direct manipulation of veins
in long procedures

3. Definition
• DVT - presence of coagulated blood or
thrombus (obstructing or non- obstructing)
in one of the deep venous conduits that
return blood to the heart.
• occurs most commonly in lower limb veins
(distal) or pelvic veins (proximal VTE)
• In pulmonary embolism, some or all of the
thrombus becomes detached and lodge in
one or more pulmonary arteries.

4. Anatomy
• Peripheral Venous System is divided into three primary groups -
superficial venous system, deep venous system and perforators
• Superficial venous system veins are the primary collecting veins of
the lower extremity. (The Greater Saphenous, Lesser Saphenous,
Posterior Arch Vein)
• Deep venous system veins receive inflow from the superficial system
• In calf, there are three groups of deep veins –
1. The anterior tibial veins, which drain the dorsal aspect of the foot
2. The posterior tibial veins, which drain the sole of the foot
3. The peroneal veins, which drain the lateral aspect of the foot

6. VIRCHOW’S TRIAD

7. • In an orthopaedic patient undergoing an operation, all of
the above pathophysiologic processes included in
Virchow’s triad are present:
• 1) use of tourniquet, immobilization and bed rest cause
venous blood stasis;
• 2) surgical manipulations of the limb cause endothelial
vascular injuries;
• 3) trauma increases thromboplastin agents; and
• 4) use of polymethylmethacrylate (PMMA) bone cement
increase hypercoagulability.
• Therefore, in patients undergoing orthopaedic surgery
and those with orthopaedic trauma, VTE prophylaxis and
adherence to the respective guidelines is paramount.

8. RISK FACTORS
• Blood stasis
1. prolong immobilisation for 3 days or more
• Long flight
• Bed ridden patient: post operative, paralysis, paresis,
plaster cast, elderly
• Endothelial Damage
1. HTN
2. Medical devices or implants

9. • Hypercoagulability:
Increased hemostasis seconadry to:
1. High PLT count (essential throbocytosis)
2. Factor V leiden defficiency, protein C and S defficiency
3. Defficiency of antithrombin lll
4. Nephrotic syndrome
5. Ocp
6. Pregnancy
7. Sle
8. Liver Ca
9. Pancreatic Ca (migratory thrombophlebitis-
Troussseau sign of malignancy)

10. CLINICAL FEATURES
• Oedema—most specific sign.
• Leg and calf pain—in 50% of patients but
nonspecific.
• Reddish purple hue of lower limb from
venous engorgement and obstruction
• Phlegmasia alba dolens (painful white
inflammation), characterized by pale
affected extremity, often having poor or
even absent distal pulses

11. • Phlegmasia cerulea dolens (painful blue inflammation)—
the leg is usually markedly oedematous, painful and
cyanotic.
• Calf tenderness—Occurs in 75% of patients, it is usually
confined to the calf muscles.
• Increased temperature or erythema in the area of DVT.
• Clinical symptoms of pulmonary embolism occur in 10%
of patients with confirmed DVT.
• Superficial thrombophlebitis—Palpable, indurated,
cordlike, tender subcutaneous venous segment.

12. Signs and Symptoms

13. Diagnosis
• Hx and Examination
• D-Dimer
• Blood Tests
• Conventional X-Ray Contrast Venogram
• Duplex Doppler Ultrasound
• Magnetic Resonance Imaging
• Radionuclide Methods

14. PHYSICAL EXAMINATION
• Homans' test Dorsiflexion of foot elicits
pain in posterior calf. Warning: it must be
noted that it is of little diagnostic value and
is theoretically dangerous because of the
possibility of dislodgement of loose clot.
• Pratt's sign: Squeezing of posterior calf
elicits pain.

17. D-Dimer Testing
• when cross-linked fibrin is degraded by plasmin, D-dimer
generates
• High sensitivity (97%) but low specificity (35%)
• Increase in Myocardial Infarction, pneumonia, sepsis,
cancer, post-op state third trimester of pregnancy,
trauma
• With low-to-moderate risk (Wells score< 2), a negative
result rules out DVT
• Further diagnostic study (e.g. duplex ultrasonography is
required in all patients with a positive D-dimer and
moderate-to-high risk of DVT (Wells score > 2).

18. USG
(of the Deep Leg Veins with Colour Doppler
Imaging of the blood flow)
• ease of use, absence of irradiation or
contrast material
• current first-line imaging examination for
DVT
• High sensitivity and specificity (95%)
• Lack of vein compressibility is the primary
diagnostic criteria
• Echogenic Thrombus within lumen
• Abnormal Doppler flow

19. MRI (Contrast Enhanced)
• Used when usg is equivocal.
• Utilizes gadolinium contrast agent which unlike
iodinated contrast agents used in venography or
CT angiography is not nephrotoxic
• Safe in Renal Insufficiency or contrast dye
allergic patients
• Detects large proximal pulmonary embolism,
inferior vena caval or iliac vein thrombois.

20. Contrast Venography
• Gold Standard for imaging DVT when
technically adequate
• Can image entire lower extremities
• Limitations- Painful, Invasive, Rarely used
now due to accuracy of non-invasive tests

21. CT venography
• uses venous phase contrast to visualize the IVC,
pelvic veins and extremity veins.
• particularly useful for diagnosis of proximal DVT
which is missed on duplex ultrasonography
• sensitive and specific for proximal vein
thrombosis.
• But may not detect the calf vein thrombosis and
non-occluding proximal vein thrombus.

22. Case Scenario
• A 46 yrs old female pt on OCP’s, K/C of ovarian Ca (currently under
Rx) and had ORIF (IMN) sec to Rt femur fracture a week back, just
arrived from a long flight with swollen Rt calf, warm ,red, tende.
There is pitting pedal edema on the rt side as well. Some collateral,
non vericose superficial veins also noticed. When rt foot
dorsiflexed, pt complained of severe pain. On compressing rt calf,
she again felt pain. Left side was normal.
1. Dx: DVT
2. Sign ellicited: Homan’s sign
3. Cause of rt ankle edema: thrombus – prevents drainage of veins –
blood pooling disal to the obstruction – inc hydrostatic pressure –
transudate – pitting edema.

24. ACCP Risk Stratification
• The ACCP classified in-hospital patients without VTE prophylaxis in
three categories (low, moderate and high risk).
• In the first category, patients who are fully mobile and those who are
mobile and undergoing minor surgery are classified as having <
10% risk.
• In the second category, most general surgery patients, open
gynaecologic or urologic surgery patients, and medical patients who
are bedridden or sick are classified as having a 10% to 40% risk.
• In the third category, the average orthopaedic patients who have
undergone hip or knee arthroplasty or sustained a hip fracture,
major trauma are classified as having 40% to 60% risk of
venographic documented DVT

25. Treat or not to Treat?
• PDVT (below
knee/distal)
should not be
ignored in
trauma patients
and suggested
that therapeutic
anticoagulation
should be
considered in
trauma patients
with BKDVT

26. ACCP ApproachPatients with isolated DDVT with
one or more of the following risk factors should
receive anticoagulant therapy for at least three
months. Those risk factors include:
1) Positive D-dimer
2) Thrombus more than 5 cm in length or in
multiple veins
3) Thrombus in close proximity to proximal
(popliteal) vein
4) Active cancer or immobility.

27. PROPHYLAXIS
-Mechanical Methods
1. Mobilization
2. Graduated compression (elastic) knee or thigh- high
stockings (GCS) – passive devices and least effective
3. Active [intermittent pneumatic compression (IPC)]
devices— good efficacy, serve as external pumps
substituting the function of calf pumps
4. Venous foot pumps (VFP) – Foot impulse technology
(FIT) and foot impulse devices

28. Advantages
• lack of bleeding potential,
• no need for laboratory monitoring and
• no clinically important side effects
• Furthermore, the effectiveness of
anticoagulants may be enhanced by some
mechanical methods.
• In particular, IPCDs stimulate endogenous
fibrinolytic activity.

29. Disadvantages
• difficulty of implementation or suboptimal compliance
issues due to the limited movement of the patient and
the discomfort
• needing to be worn continuously pre-, intra- and post-
operatively for 72 hours, and
• lack of powerful evidence that any of the mechanical
VTE prophylaxis methods may reduce the risk of death
or PE.
• Concerning GCS, these need to be sized and fitted
properly, while it has been reported that they can cause
impairment in tissue oxygenation.
• Additionally, situations such as open fractures, peripheral
arterial insufficiency, severe cardiac insufficiency,
infection and ulceration of the lower limbs are
contraindications for the use of mechanical VTE
methods.

30. -Pharmacologic Methods
1. Antithrombotics Include anticoagulants and
antiplatelet
2. Oral vitamin K antagonist, warfarin
3. Oral aspirin (antiplatelet drug)
4. Subcutaneous Pentasaccharide- fondaparinux
(selective inhibitor of Xa)
5. Subcutaneous unfractionated heparin (UFH) or
LMWH
6. Oral direct factor Xa inhibitors
7. Oral direct thrombin inhibitor—dabigatran
etexilate, ximelagatran
8. Thrombolytic drugs (primary thrombolytic drugs
are not used for prophylaxis)

31. Prevention
• Identify patient at risk
• Prevent Dehydration
• Encourage movement
• Exercise
• Quit smoking

32. Low-Molecular-Weight Heparins
• molecular weight is approximately one-third that of UFH
• Greater bioavailability
• More predictable dose response, and
• a longer half- life than does UFH
• No monitoring or dose adjustment required
• Adult 7500 -10000 IU followed by 1000 – 1500 IU/ hr in infusion
• Child 50-100 U/kg
UFH
• The heparin/AT (anti thrombin) complex inactivates thrombin (factor IIa) and factors Xa, IXa, XIa and XIIa.
• intravenous (IV) infusion and subcutaneous
• Bleeding risk in trauma and surgery pts
• Monitored usinf APTT
• 1 mg of protamine sulphate will neutralize approximately 100 IU of UFH.
Fondaparinux –
• An anti-Xa pentasaccharide –
• Administered as a once-daily subcutaneous
• No laboratory monitoring is required.
• Patients weighing <50 kg receive 5 mg, patients weighing 50–100 kg receive 7.5 mg, and
• patients weighing >100 kg receive 10 mg5.
Warfarin
• Vitamin K antagonist
• Prevents carboxylation activation of coagulation factors II, VII, IX, and X.
• Requires at least 5 days to act fully
• Usually initiated in a dose of 10 mg in first and second day, on 3rd day 5 mg subsequent doses is titratedd against the INR
• Doses of 7.5 or 10 mg can be used in obese patients
• A therapeutic INR range of 2.0 to 3.0 with a target INR of 2.5 is recommended
• INR monitoring following 2nd dose then 4 weekly and if stable 12 weekly

33. Prophylaxis regimen in some
orthopeadic surgeries
Elective Hip Replacement
• LMWH1 (for 10 days) followed by aspirin (75 or
150 mg) for a further 28 days.
• LMWH1 (for 28 days) combined with anti-
embolism stockings (until discharge).
• Consider apixaban or dabigatran etexilate if none
of the options above can be used.
• Consider anti-embolism stockings until discharge
from hospital if pharmacological interventions
are contraindicated in people undergoing
elective hip replacement surgery.

34. Elective knee replacement
• Aspirin (75 or 150 mg) for 14 days.
• LMWH1 (for 14 days) combined with anti-
embolism stockings (until discharge).
• Rivaroxaban
• Consider apixaban or dabigatran etexilate if none
of the options above can be used..
• Consider intermittent pneumatic compression if
pharmacological prophylaxis is contraindicated
in people undergoing elective knee replacement
surgery. Continue until the person is mobile

35. Fragility fractures of the Pelvis, Hip and
Proximal femur
• Offer VTE prophylaxis for a month to people with
fragility fractures of the pelvis, hip or proximal
femur
• Choose either: LMWH, starting 6–12 hours after
surgery or
• fondaparinux sodium starting 6 hours after
surgery, providing there is low risk of bleeding

36. Foot and ankle surgery
• that requires immobilisation (for example,
arthrodesis or arthroplasty);
• consider stopping prophylaxis if immobilisation
continues beyond 42 days
• when total anaesthesia time is more than 90
minutes or
• the person's risk of VTE outweighs their risk of
bleeding.

37. Upper limb surgery
• VTE prophylaxis is generally not needed if giving
local or regional anaesthetic for upper limb
surgery.
• Consider VTE prophylaxis for people undergoing
upper limb surgery if the person's total time
under general anaesthetic is over 90 minutes or
where their operation is likely to make it difficult
for them to mobilise.

38. Acute DVT Mx
• Anticoagulation with unfractionated or low-molecular-weight heparin
remains the mainstay of treatment
• Recent studies have demonstrated that early clot lysis through the
use of catheter-directed thrombolytic therapy and other adjunctive
endovascular techniques rapidly restores venous patency, more
effectively preserves valvular function, and improves quality of life.
When used in conjunction with anticoagulation, these minimally
invasive endovascular techniques have the potential to lead to
improved long-term outcomes in patients with DVT.
• These comprise catheter-directed thrombolysis, percutaneous
mechanical thrombectomy devices, adjuvant venous angioplasty
and stenting, and inferior vena cava

39. Regimen for Acute DVT
1) apixaban 10 mg twice a day for 7 days, then 5 mg twice
a day;
2) dabigatran 150 mg twice a day after a 5- to 10-day
lead-in course of LMWH;
3) edoxaban 60 mg daily (30 mg if creatinine clearance
30-50 ml/min or potent proton pump inhibitor use) after
a 5- to 10-day lead-in course;
4) rivaroxaban 15 mg twice a day for 21 days, then 20 mg
daily; or
5) warfarin with a goal international normalized ratio (INR)
2-3 and LMWH for 5-10 days (until INR >2).

40. Management Duration
Clinical situation Duration
VTE provoked by transient major risk
factor
3 months
Distal unprovoked DVT or PE
3 months
First unprovoked proximal DVT or PE
6 months
First unprovoked VTE plus
Active malignancy
Multiple thrombophilias
Antiphospholipid syndrome
indefinite
Recurrent unprovoked VTE
indefinite

41. Conclusion
• Compared to a single modality, combined
prophylaxis significantly decreases the
incidence of both DVT and PE.
• Therefore identification of pts at risk is
important.