DVT PROPHYLAXIS IN ORTHOPEDIC SURGERIES

PRESENTED BY –DR SOUVIK PAULMODERATED BY –DR PRINCE RAINA

What Is Deep Vein Thrombosis ?

INTRODUCTION • WHAT IS VTE ?

• includes spectrum of deep vein thrombosis (DVT) and pulmonary embolism (PE).

NEED OF DVT PROPHYLAXIS

.common preventable cause of hospital deaths

DVT in traumatic injuries 5 - 63%

Without prophylaxis

venous thrombosis -- 50% Orthopedic surgeries

Fatal PE in 2.0% of total hip arthroplasty

Fatal PE in 2.5-7.5% of Fractured Hip

Ref: Campbell 12th edition Piotrowski JJ, et al Am J Surg. 1996 Aug; 172(2):210-3.

Indian J Urol. 2009 Jan-Mar; 25(1): 11–16.doi: 10.4103/0970-1591.45531

INCIDENCE OF DVT IN DIFFERENT SURGERIES

Patient group VTE prevalence (%)

Medical patients 10-20

Cardiac patients 15-40

Neurosurgery 15-40

Stroke 20-30

Hip and knee arthroplasty 40-60

Major trauma 40-50

Spinal cord injury 60-80

Critical care patients 10-20

Strong risk factors

1. Hip or leg fracture

2. Hip or knee replacement

3. Major general surgery

4. Major trauma, including spinal cord injury

Moderate risk factors

1. Arthroscopic knee surgery

2. Central venous catheterization

3. HRT or OC Pills

4. Malignancy (active or recently treated)

5. Pregnancy

6. Paralytic stroke

7. Prior VTE

8. Thrombophilia (inherited or acquired)

Weak risk factors

1. Bed rest > 3d

2. Prolonged immobility

3. Advanced age

4. Laparoscopic surgery

5. Obesity

6. Pregnancy

7. Varicose veins

Anderson FA Jr,Spencer FA: Risk factors for venous thromboembolism Circulation107[23, Suppl 1]:I9,2003

PATHOPHYSIOLOGY

• virchow's triad

Presentation and Physical Examination

• Calf pain or tenderness

• Swelling + pitting oedema

• Increased skin temperature and fever

• Superficial venous dilatation

Clinical examination

• Palpate distal pulses

• Evaluate capillary refill .

• Neurologic evaluation

• Homans sign: pain posterior calf /knee with forced dorsiflexion of foot.

• Moses sign Gentle squeezing of lower part of calf from side to side.

• Neuhofs sign Thickening and deep tenderness elicited while palpating deep in calf muscles

Wells Clinical Prediction Guide

Variable Wells

Active cancer ( within last 6 months or palliative) 1

Calf swelling >3 cm compared to other 1

Collateral superficial veins 1

Pitting edema 1

Swelling of entire leg 1

variable wells

Paralysis, paresis, or recent cast immobilization of lower extremities 1

Recently bedridden > 3 days, or major surgery 1

Previous DVT 1

Alternative diagnosis at least as likely deep vein thrombosis-2

Localized pain along distribution of deep venous system 1

Interpretation

High probability: ≥ 3 (Prevalence of DVT - 53%)

Moderate probability: 1-2 (Prevalence of DVT - 17%)

Low probability: ≤ 0 (Prevalence of DVT - 5%)

Adapted from Anand SS, et al. JAMA. 1998; 279 [14];1094

Over 20 different VTE risk assessment models

• Individualized point-based scoring models e.g.:CAPRINI PADUA REVISED GENEVA SCORE

• Grouping or “bucket” models:– NICE / NHS guidelines – Classic “3 bucket” model

A TOTAL SCORE >4 INDICATES HIGH RISK OF VTE

Interpretation of revised Geneva score

0-3 score : low risk

4-10 score : intermediate risk

>11 score : high risk

.

• Validated in predicting risk

• Can be difficult to use reliably

Caprini Model

1 point for each risk factors

• Age 41-60

• Swollen legs

• Varicose veins

• Obesity

• Sepsis

• OCP or HRT

• Pregnancy or postpartum

• AMI

• CHF

• Prolonged bed rest

• Prior major surgery

2 points for each risk factors

• Age 61-74 yrs

• Arthroscopic surgery

• Malignancy

• Laparoscopic surgery

• Immobilisation with plaster cast (<1 month)

3 points for each risk factor

• Age >75 yrs

• History of DVT /PE

• Positive factor leiden

• Family history of VTE

• Positive lupus anticoagulant

• HIT

• Elevated anticardiolipin antibodies

5 points for each risk factors

• Stroke (<1 months)

• Elective major lower limb arthroplasty

• Hip ,pelvic , leg fractures(<1 month)

• Spinal cord injury (<1 month)

PROPHYLAXIS PROCEDURES

1. Mechanical

2. Pharmacological

Mechanical

1. Physiotherapy

2. Graduated Compression Stockings (GCS)

3. Intermittent Pneumatic Compression Devices (IPC)

and Venous foot pumps (VFP).

4. IVC filters

Graduated Compression Stockings (GCS)

GRADUATED COMPRESSION STOCKINGS

Update of

Elastic compression stockings for prevention of deep vein thrombosis. [Cochrane Database Syst Rev. 2010]

19 RCTs

1681 individual patients and 1064 individual legs (2745 analytic units).

9 TRIALS- general surgery,

6 TRIALS- orthopaedic surgery,

1 TRIAL- medical patients.

G c s applied on the day before surgery or on the day of surgery . worn up until discharge or until the patients were fully mobile

Treatment group (GCS) of 1391 units -126 developed DVT

control group (without GCS) of 1354 units - 282 developed DVT

odds ratio was 0.33 (95% CI) 0.26 to 0.41 (P < 0.00001).

INTERMITTENT PNEUMATIC COMPRESSION [IPC]

• Inflation Cycle :10-20 secs

• Deflation cycle :30 secs

• At 40 mm Hg -maximum velocities with calf and/or thigh compression –

Femoral velocity- 35–60 cm/s with augmentations at around 50–250%

popliteal velocities -55 cm/s.

At 120 mm Hg – peak velocities of >100 cm/s in both popliteal and

femoral veins

• Foot compression has produced more modest results

20–40 cm/s -femoral vein 30–55 cm/s - popliteal vein

TYPES OF IPC

•.

A: Venous blood flow velocity in the posterior tibial vein during compression by a foot cuff (velocity/ time

B: Venous blood flow velocity in the femoral vein during compression by a foot cuff (velocity [cm/s] vs. time [1 second per vertical dotted line]).

Problems in IPC

Improperly fitted compression stockings

reversed pressure gradient

higher incidence of VTE

CONTRAINDICATION OF IPC

• Severe arteriosclerosis

• Severe CHF

• Known acute DVT

• Gangrene

• Dermatitis

• Skin grafting

The Cochrane Peripheral Vascular Diseases Group Trials

RCT with 121 study participants comparing 2 types of IPC devices

• no cases of symptomatic DVT or PE during first 3 weeks after THR.

• calf-thigh pneumatic compression more effective

for reducing thigh swelling during early post-operative stage

Equal evidence regarding both types

DVT PUMP

• SET Pressures:

uniform thigh and calf / uniform calf garment 40 mmhg

sequential thigh and calf /sequential calf garment 45 mmhg

foot garment 130 mmhg

IVC filters

• FDA approved

• Ideal for young patients with reversible

PE risk factors

Indications• Proven VTE

• Recurrent VTE

• Contraindications to anticoagulation

• Short Term Risk of PE/Short Term contraindication of

anticoagulation :retrievable filter

• Uncertain Risk of PE and/or lack of control for anticoagulation :

Permanent Filter

• Long Term Risk of PE/Recurrent PE/Recurrent DVT: Permanent Filter

SIDE EFFECTS

• Device-associated morbidity

• Device migration

• Filter embolization

• Filter fracture

• Insertion-site thrombosis

• Perforation of the vena cava

• Recurrent DVT

• Recurrent PE

• Thrombotic complications

• Vena cava thrombosis

Pharmacological:

1. Oral antiplatelet agents

2. Injectable low-molecular-weight heparins

3. Injectable unfractionated heparin

4. Injectable or oral factor Xa inhibitors

5. Injectable or oral direct thrombin inhibitors

6. Oral vitamin K antagonists

Oral antiplatelet agents

• Aspirin Permanently inhibits COX-1 and COX-2

• Dipyridamole Inhibits PDE; increases Camp

• Ticlopidine• Clopidrgrel• Abciximab • Eptifibatide • Tirofiban

Aspirin

• Dosage : 75 mg OD

• ACCP and AAOS guidelines do not include aspirin in prevention of VTE

• Present indications:

1.elective TKR

2.elective THR

3.contraindication to other pharmacologic prophylaxis

Contraindications to Antiplatelet Therapy

- Recent thoracic, abdominal, or cns surgery

-Recent CVA , trauma, or neoplasm

-Bleeding ulcer

-Hypertension

-Anticipated invasive procedures

-Concurrent hemostatic dysfunction

Heparin

• Types :

Un fractionated heparin(UFH) : inhibit factor II and X

Dose for DVT prophylaxis: 5000 u sc every 8 to 12 hours

Monitoring : aPTT

More risk for bleeding and heparin induced thrombocytopenia(8%)

Antidote: Protamine sulphate

LMWH• Examples: enoxaparin, dalteparin, tinzaparin

• Inhibit thrombin only

• Dose in prophylaxis : 40 mg in 0.4 mL SC OD

• Lesser risk of and bleeding HIT

• No need to regular monitoring

• No antidote

Baseline Postoperative Risks of VTE Outcomes in the Absence of Pharmacological Prophylaxis

• Outcome Total Hip Replacement

Strength of Evidence(THR)

Total Knee Replacement

Strength of Evidence(TKR)

Pulmonary embolism

6% Low 1% Low

Deep vein thrombosis

39% Low 46% Low

Major bleeding

1% Moderate 3% Low

Minor bleeding

5% Low 5% Moderate

Sobieraj DM, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm

Comparative Effectiveness of Pharmacological Prophylaxis Agents: LMWH Versus UFH

Comparators DVT PE Major Bleeding

Heparin-induced Thrombo-cytopenia

LMWH vs. UFH

Decreased risk by 20%

RR 0.80

Decreased odds by 52%

OR 0.48

Decreased odds by 35%

OR 0.57

Decreased odds by 88%

OR 0.12

Sobieraj DM, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm

warfarin

• Vitamin k antagonist

• Cause defective coagulation

• Slow in onset

• Good oral absorption

• Monitor with PT and INR

Comparative Effectiveness of Pharmacological Prophylaxis Agents: LMWH Versus Warfarin

Comparators DVT Proximal DVT

SymptomaticVTE

PE

LMWH vs. warfarin

Decreased risk by 34%

RR 0.66

No difference;

RR 0.63

No difference;

OR 1.00

No difference;

OR 1.11

Sobieraj DM, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm

Fondaparinux

– Synthetic Factor Xa inhibitor

– FDA approved for prophylaxis, treatment

• Prophylaxis: 2.5/d SC

• Treatment: weight based 5, 7.5 or 10/d SC

– Start warfarin simultaneously, continue 5-7 days as with heparin

• Avoid with GFR < 30

Comparative Effectiveness of Pharmacological Prophylaxis Agents: Enoxaparin Versus Fondaparinux

Comparators DVT Symptomatic VTE

PE Major Bleeding

Enoxaparinvs. fondaparinux

Relative risk is higher for enoxaparinby 99%

RR 1.99

No difference;

OR 0.70

No difference

OR 3.34

Decreased odds by 35%

OR 0.65

Sobieraj DM, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm

Ximelagatran• Direct thrombin inhibitors

• Alternative to warfarin

– Oral - fixed dose

• Acute clot or orthopedic prophylaxis: 36 mg bid

• Secondary prevention: 24 mg bid

– No monitoring, no initial heparin

• Safety questions

– No antidote

– Can elevate LFTs

NICE Guidelines 2015

Elective hip / knee replacement

Start mechanical VTE prophylaxis at admission

• anti embolism stockings (GCS)‑

• foot impulse devices

• intermittent pneumatic compression (IPC)devices

Continue mechanical VTE prophylaxis until the patient no longer has significantly reduced mobility.

If no contraindications, start pharmacological VTE prophylaxis after surgery

• dabigatran etexilate 1–4 hours after surgery

• fondaparinux sodium 6 hours after

• LMWH 6–12 hours after

• Rivaroxaban 6–10 hours after

• UFH (for renal failure patients) 6–12 hours after

Continue pharmacological VTE prophylaxis for 28–35 days in hip replacements Continue pharmacological VTE prophylaxis for 10-14 days in knee replacements

• Hip fractures:

Start mechanical VTE prophylaxis at admission

•Anti embolism stockings ‑

•Foot impulse devices

•Intermittent pneumatic compression devices (thigh or knee length).

Continue mechanical VTE prophylaxis until the patient no longer has significantly

reduced mobility.

If no contraindications, start pharmacological VTE prophylaxis after surgery

• fondaparinux sodium not recommnded pre op,

can be given 6 hrs post op

• LMWH start at admission,

stop 12 hr before restart 6–12 hours after surgery

• Rivaroxaban 6–10 hours after

• UFH (for CRF) start at admission

stop 12 hr before Restart 6–12 hours after surgery

• Continue pharmacological VTE prophylaxis for 28–35 days

Other orthopaedic surgery

Start mechanical VTE prophylaxis at admission.

• Anti embolism stockings ‑

• Foot impulse devices

• Intermittent pneumatic compression devices (thigh or knee length).

Continue mechanical VTE prophylaxis until the patient no longer has significantly

reduced mobility.

.Pharmacological VTE prophylaxis 6–12 hours after surgery.

• LMWH

• UFH (for renal failure).

• Continue pharmacological VTE prophylaxis until patient no longer has

significantly reduced mobility.

DVT prophylaxis : ORTHOPEDICS SURGERY

• Low risk

– Early ambulation

• Moderate risk

– UFH 5000 u sc bid or LMWH, IPC

• High risk

– LMWH - may combine with IPC

AAOS Clinical Practice Guideline

Schematic of estimated incidence rates for LMWH and no prophylaxis for major orthopaedic surgery

• Ref:Prevention of VTE in orthopedic surgery patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.

• Falck-Ytter Y1, Francis CW, Johanson NA, Curley C, Dahl OE, Schulman S, Ortel TL, Pauker SG, Colwell CW Jr;

Systematic Review – Regarding DVT Prophylaxis

Meta regression analysis

Compare other therapies to enoxaparin for prevention of VTE following THR

Dranitsaris 2011 http://www.aaos.org/

Low-molecular-weight heparin and intermittent pneumatic compression for thromboprophylaxis in critical patients

BING WAN, et al Oct 13. 2015 PMC

• 500 patients were divided into four groups

• IPC( int. Pneumatic compression) 95

• LMWH 185

• LMWH + IPC 75

• control 145

Doppler study diagnosis done

Incidence of DVT, PE and complications of treatment in the four groups.

Group No. of patients DVT cases PE cases Bleeding cases

IPC 95 9 28 0

LMWH 185 31 4 18

LMWH + IPC 75 0 0 3

Control 145 49 29 0

conclusion

• LMWH combined with IPC exhibited an excellent prophylactic effect against DVT and PE.

• RR : 0.281 for IPC,

• RR: 0.49 for LMWH.

Comparative efficacy and safety of anticoagulants and aspirin for extended treatment of venous thromboembolism: A network meta-analysis

Diana M. Sobieraj et al

systematic literature search and searching of reference lists

identify RCT of patients completed initial anticoagulant treatment for VTE

randomized for the extension study

comparison of anticoagulant treatment to placebo

.• Ten trials (n = 11,079) were included.

• Apixaban ,dabigatran, rivaroxaban, idraparinux and vitamin

K antagonists (VKA) reduced risk of VTE recurrence

compared to placebo.

COMPARATIVE EFFICACY AND SAFETY OF NEW ORAL ANTICOAGULANTS(NOAC) VERSUS WARFARIN FOR LONG-TERM TREATMENT OF VENOUS THROMBOEMBOLISM: A META-ANALYSIS

Ajay Vallakati et al

• We searched PubMed, Cochrane library and Embase for RCTs comparing

NOACs (dabigatran, apixaban, rivaroxaban, and edoxaban) with placebo or

warfarin for long-term treatment of VTE

5 RCTs (n=16117) compared

NOACs (n=8484)

with either placebo (n=2085)

or warfarin (n=5548).

NOACs significantly reduced the risk of VTE

when compared to placebo/ warfarin (OR: 0.33; 95% CI, 0.13 −0.87)

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THANK YOU

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