PREVENTION OF DVT AND
PE IN SURGICAL
Venous Thromboembolism
Compromise DVT and PE
Strikes more than 1 in 1000 adults per year, causing
discomfort, suffering, and occasionally death.
300 000 new cases are diagnosed yearly in the
united states.
How ever probably 3 to 4 times as many cases occur
without obvious symptoms and are never detected.

CASE STUDY

Mrs fatema is a 48-year-old house wife who
presents to a ER complaining of a swollen right calf
that has appeared over that last few hours.
What is your differential diagnosis for an acutely
swollen limb?
DDX
Deep vein thrombosis (DVT)
2.
Cellulitis
3.
Ruptured Baker’s cyst
4.
Muscular strain
5.
Septic arthritis
6.
Lymphoedema
7.
Pelvic tumor (e.g. ovarian) compressing iliac vein .
8.
Allergic reaction to insect bite .
9.
Compartment syndrome.
What specific questions would you ask Mrs fatema inyour
history-taking?
1.
History taking for swollen limb
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Onset.
Duration.
Site.
How { spontaneous , activity}
Other sites are swollen.
Where did the swelling start .
Painful ?
Change during the day ?
Fever ?
Is the swelling get bigger ?
Does the movement of the leg increase the pain ? Inflammation
Septic arthritis
Compartment syndrome .
DVT
Painful , warm swelling, sudden .
 Are there any risk factors for venous thrombosis?
− Hypercoagulable blood?
Thrombophilia in the family
OCPs.
Obesity
Cancer history .{ weight loss , change in apatite , night sweating
}
Pregnancy.
− Stasis? Bed rest (>3 days) or long flight (>12 hours)
− Vessel injury? Trauma, surgery.

History taking for swollen limb

Has he felt breathless, had any chest pain, or
coughed up any blood?
Cellulites
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painful , redness , hotness , get bigger , increase with
movement , fever, painful to touch :
Hx of penetrating injury :
Cuts , bites, wounds, or superficial infections”port of
entry “
Pt. has risk factors :
History of immunosuppression.
DM
Compartment syndrome
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Sever calf pain.
Numbness .
Pale limb .
Weakness .
Cold feeling .
History taking for swollen limb

Has she had any abdominal pain? Has she noticed
any blood in her faeces? Has she had any unusual
vaginal bleeding? Has she noticed any weight
loss, fever, or malaise? If you are considering a
pelvic malignancy as the cause of the limb swelling,
you can ask for symptoms that are suggestive of
colon, ovarian, or uterine malignancies.
History taking for swollen limb
Has she recently had radiotherapy or surgery to
her right leg or abdomen?
Radiotherapy or surgery may have damaged the
lymphatic drainage from her affected limb, causing
the accumulation of lymph (lymphoedema).

Physical examination


Proper exposure .
General observation of the patient (looks well? ,
conscious? , oriented? , breath comfortably (short
of breath or chest pain may indicate PE after
DVT)? , not in pain? , not pale, jaundiced or
cyanosed (Liver Failure, Heart Failure)? , if there
is any IV lines or dressings or masks? .. ).
Physical examination
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vital signs (Temp., BP, Pulse Rate, and respiratory
rate)
Very important in pt. with :
Cellulites. { pt may have septicemia}
DVT . { PE }
Question

Pt. with septicemia , what is the first vital sign to
affected ?
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Physical examination
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Inspection:
Inspect both legs and compare them: if there are
swelling : if has raised , sharply defined margin .
This is for ??
Redness
ulcers
Port of entry for cellulites. { examine between the
toes also for fungal infection as a portal of entry.
Dilated veins .
Changes in the skin color, such as turning pale, red
or blue.
Physical examination
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Palpation :
1) use the dorsum of your hands to feel the
temperature of the legs bilaterally.
Ask about pain : palpate for any tenderness each leg
separately. { tenderness is present in 75% of pt.
With DVT and usually in the calf muscles }.
Assess if the edema is pitting or not ?
check the pulses (Dorsalis pedis, Tibialis posterior,
and Popliteal).

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• Homan’s Sign
with the leg extended at the knee joint, make a
forceful dorsiflexion of the foot at the ankle, this
may elicit a pain in the calf which may indicate
DVT.
it is not used anymore because it has low
specificity and may increase the risk of the
thrombus to be dislodged, so increase the risk of
PE
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measure the diameter of the legs:
localize the tibial tuberosity and using the tape to
measure 10 down from the tibial tuberosity and
then measuring the diameter at that point using
the tape. Do the same thing bilaterally.

Keep in mind that a difference of
significant.
3 cm or more is

mark the area of swelling with a pen so that you
can monitor a progressing cellulites.
Others
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Lymphadenopathy: check for swollen lymph nodes
along the affected leg and in the inguinal fold, as
lymphadenopathy would be highly suggestive of an
infection in the limb.
Between the lymph nodes and the site of swelling :
look for red streaks ??
Abdominal masses: an abdominal mass in the right
lower quadrant would suggest a tumour that could
be compressing the right iliac vein.
Deep venous thrombosis (DVT)
DVT is the presence of coagulated blood, a thrombus,
in one of the deep venous conduits that return blood
to the heart.
Epidemiology
 DVT is one of the most prevalent medical problems
today, with an annual incidence of 80 cases per
100,000.
 Each year in the United States, more than 200,000
people develop venous thrombosis; of those, 50,000
cases are complicated by PE.

Thrombus
DVT Pathophysiology
Rudolf Virchow described 3 factors that are
critically important in the development of venous
thrombosis:
(1) Venous stasis,
(2) Activation of blood coagulation
hypercoagulability. , And
(3) Endothelial damage. These factors have come to
be known as the virchow triad.
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DVT Pathophysiology-stasis
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Microscopic thrombus formation and thrombolysis
(dissolution) are continuous events, but with increased
stasis, procoagulant factors, or endothelial injury, the
coagulation-fibrinolysis balance favor the pathologic
formation of an obstructive thrombus.
Venous stasis can occur as a result of anything that slows
or obstructs the flow of venous blood; mainly caused by
heart failure, prolonged immobility such as Stroke,
paralysis due spinal cord injury.
But can occur in prolonged bed rest, and long flight.
Endothelial injury
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Disrpution the endothelial cell barrier expose the
subendothelium. Platelets adhere to the
subendothelial surface by means of von Willebrand
factor or. Neutrophils and platelets are activated,
releasing procoagulant and inflammatory mediators.
mainly caused by either direct trauma (severed vein)
or local irritation (by chemotherapy, past DVT,
phlebitis)
Hypercoagulability
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A hypercoagulable state can occur due to a
biochemical imbalance between circulating factors. This
may result from an increase in circulating tissue
activation factor, combined with a decrease in
circulating plasma antithrombin and fibrinolysins.
Hypercoagulability: inherited (AT III def., protein C, S
deficiency) or acquired (malignancy, pregnancy, AT III
def., protein C, S deficiency as in nephritic syndrome,
DIC and liver failure, Sepsis, Birth control pills or
hormone replacement therapy.
Signs and symptoms of DVT
In about half of all cases, deep vein thrombosis occurs
without any noticeable symptoms.
When deep vein thrombosis symptoms occur, they can
include:
1.
2.
3.
4.
Swelling in the affected leg, including swelling in your ankle
and foot.
Pain in your leg; this can include pain in your ankle and foot.
The pain often starts in your calf and can feel like cramping
or a charley horse.
Warmth over the affected area.
Changes in your skin color, such as turning pale, red or blue.
Signs and symptoms of DVT
The warning signs and symptoms of a pulmonary
embolism include:
1.
Unexplained sudden onset of shortness of breath
2.
Chest pain or discomfort that worsens when you take a
deep breath or when you cough- pleuritic chest pain
3.
Feeling lightheaded or dizzy, or fainting.
4.
Sweating
5.
Coughing up blood
6.
A sense of anxiety or nervousness
7.
Rapid pulse
WORK UP
D - D i m e r Te st i ng
 D-dimers are degradation products of cross-linked
fibrin by plasmin that are detected by diagnostic
assays.
 he D-dimer assay has a high sensitivity (up to 97%);
however, it has a relatively poor specificity (as low as
35%) and therefore should only be used to rule out
DVT, not to confirm the diagnosis of DVT.
 A negative D-dimer assay result rules out DVT in
patients with low-to-moderate risk (Wells DVT score <
2).
WORK UP
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A negative result also obviates surveillance and
serial testing in patients with moderate-to-high risk
and negative ultrasonographic findings. All patients
with a positive D-dimer assay result and all patients
with a moderate-to-high risk of DVT (Wells DVT score
>2) require a diagnostic study (duplex
ultrasonography).
The D-dimer result should be disregarded in high-risk
patients, as further investigation is mandatory even if
it is normal
Normal range: <250ng/dl
WORK UP
C o a g u l a t io n P r o f i l e
Imaging studies
 Doppler ultrasound is the current first-line imaging
examination for DVT because of its relative ease of
use, absence of irradiation or contrast material, and
high sensitivity and specificity in institutions with
experienced sonographers.
 MRI is the diagnostic test of choice for suspected iliac
vein or inferior vena caval thrombosis.
WORK UP
Chest x-ray
ECG
A r t e r i a l bl ood g a s e s
MANAGMENT
The mainstay of medical therapy has been
anticoagulation
H e pa r i n U s e i n D e e p Ve nous T hr om bos i s
 Heparin products used in the treatment of deep
venous thrombosis (DVT) include unfractionated
heparin and low molecular weight heparin (LMWH).
Heparin prevents extension of the thrombus and has
been shown to significantly reduce (but not eliminate)
the incidence of fatal and nonfatal pulmonary
embolism and recurrent thrombosis.
 Dependent on antithrombin activity.

Heparin Use in Deep Venous Thrombosis
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The larger fragments exert their anticoagulant
effect by interacting with antithrombin III (ATIII) to
inhibit thrombin. ATIII, the body’s primary
anticoagulant, inactivates thrombin and inhibits the
activity of activated factor X (Xa) in the coagulation
process.
The low-molecular-weight fragments exert their
anticoagulant effect by inhibiting the activity of
activated factor X.
Heparin Use in Deep Venous Thrombosis
Dosage
The dose is based on the patient’s weight and there is
usually no requirement to monitor tests of
coagulation.
 Anti dote protamine sulfate
Fondaparinux
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Fondaparinux, a direct selective inhibitor of factor xa,
overcomes many disadvantages of LMWHS.
Single-daily subcutaneous dose is required.
Therapeutic monitoring of laboratory parameters such as
the prothrombin time or aptt is also not required.
To be used with caution in patients with renal insufficiency
It is eliminated via the kidneys
Its half-life is considerably longer than those of the lowmolecular-weight heparins.
Warfarin
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A vitamin K antagonist – remains the most commonly
used oral anticoagulant.
Warfarin inhibits the vitamin K-dependent synthesis of
biologically active forms of the calcium
dependent clotting factors II, VII, IX and X, as well as
the regulatory factors protein C, protein S, and protein
Z.
Warfarin
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
Therapy is initiated with a high loading dose,
followed by a maintenance dose based on the
international normalised ratio (INR). LMWH should not
be discontinued until the INR is 2 or more for at least
24 hours.
Due to the narrow therapeutic index of warfarin and
its propensity to interact with other drugs and food,
regular measurement of the INR is required
throughout the duration of anticoagulation.
Warfarin
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It has several adverse effects but the most common
adverse effect is hemorrhage which increased when
warfarin is combined with antiplatelet drugs
Other adverse effects are osteoporosis , warfarin
necrosis and purple toe syndrome .
Warfarin is contraindicated in pregnancy as it passes
through the placental barrier and may causes
bleeding in the fetus .
Duration of anti coagulation
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In patients with an identifiable and reversible risk factor,
anticoagulation may be safely discontinued following 3
months of therapy.
Those with persistent prothrombotic risks or a history of
previous emboli should be anticoagulated for life.
In patients with cancer-associated VTE, LMWH should be
continued for at least 6 months before switching to warfarin.
For patients with unprovoked VTE, the appropriate
duration of anticoagulation should be at least 3 months, but
prolonged therapy should be considered in males (who
have a higher risk of recurrent VTE than females),.
Duration of anti coagulation
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The disadvantages of prolonged anticoagulation
range from the inconvenience of long-term INR
monitoring to the more serious risk of major
haemorrhage (around 3% per year). Life-threatening
haemorrhage occurs in around 1% of cases per year
and fatal bleeding in 0.25% cases per year.
Aspirin
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Considered as NSAIDs but it’s now rarely used as an
anti-inflammatory medication .
used as an analgesic to relieve minor pains and as
an antipyretic to reduce fever.
Aspirin also has an antiplatelet effect by inhibiting
the production of thromboxane.
Aspirin
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Low doses of aspirin ( 81-325 mg once daily ) is also
used to help prevent heart attacks, strokes, and blood
clot formation in people at high risk of developing
blood clots.
Aspirin inhibits the synthesis of thromboxane A2 by
irreversible acetylation of the enzyme
cyclooxygenase.
Aspirin
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It’s Half-life : 0.25 hr .
Aspirin’s main adverse effects at antithrombotic doses are
gastric upset and gastric and duodenal ulcer.
Hepatotoxicity, asthma, rashes, gastrointestinal bleeding .
The antiplatelet action of aspirin contraindicates its use by
patients with hemophilia.
NOTE : aspirin and warfarin should be stoped before surgery
and can be replaced by heparin because if bleeding occur
while using heparin we can give anti dote and there is no
anti dote for warfarin and aspirin.
Prevention of DVT
Break virchow’s triad
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Life style modification
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Mechnical measuers
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Pharmacoligical measures
Prevention of DVT in surgical patient –
Based on Risk Stratification
Risk factors are grouped according to severity and are added
to produce an overall risk factor score, which corresponds to a
low through a very high potential for DVT development, upon
which prophylaxis is given:
In risk factor assessment, 1 point is assigned to each of the
following:
1.
Age 41-60 years
2.
Minor surgery
3.
History of major surgery within 1 month
4.
Pregnancy or postpartum within 1 month
5.
Varicose veins
6.
Inflammatory bowel disease
7.
Swelling of legs

Prevention of DVT in surgical patient –
Based on Risk Stratification
Each of the following risk factors is assigned 2 points:
1.
Age older than 60 years
2.
Malignancy or current chemotherapy or radiation
therapy
3.
Major surgery (>45 min)
4.
Laparoscopic surgery (>45 min)
5.
Confined to bed longer than 72 hours
6.
Immobilizing cast shorter than 1 month
7.
Central venous access for less than 1 month
8.
Tourniquet time longer than 45 minutes
Prevention of DVT in surgical patient –
Based on Risk Stratification
The following risk factors are assigned 3 points each:
1.
Age older than 75 years
2.
History of DVT or pulmonary embolism (PE)
3.
Family history of thrombosis
4.
Factor V Leiden/activated protein C resistance
5.
Medical patient with risk factors of myocardial
infarction, congestive heart failure, or chronic
obstructive pulmonary disease
6.
Congenital or acquired thrombophilia
Prevention of DVT in surgical patient –
Based on Risk Stratification
Finally, 5 points are assigned to each of the following
risk factors:
1.
Major, elective lower extremity arthroplasty, total
knee replacement (TKR), total hip replacement
(THR)
2.
Hip, pelvis, or leg fracture within 1 month
3.
Stroke within 1 month
4.
Multiple trauma within 1 month
5.
Acute spinal cord injury with paralysis within 1
month
Prevention of DVT in surgical patient –
Based on Risk Stratification
Low-risk patients have a score of 1 or less:
The risk of calf DVT in this group is estimated to be 2-5%
without prophylaxis, and the risk of clinical pulmonary
thrombosis is 0.2% No specific prophylaxis is required in
this group other than early and aggressive mobilization.
 Moderate-risk patients have a score of 2 or less
Havea moderate risk of DVT, which is estimated at 10-20%.
The risk of clinical PE in this group is 1-2%. Successful
prevention strategies in this group consist of low-dose
unfractionated heparin , low-molecular-weight heparin
(LMWH) , and graduated compression stockings (GCS) or
intermittent pneumatic compression (IPC).

Prevention of DVT in surgical patient –
Based on Risk Stratification
The highest-risk patients have a score of 5 or greater:
carry an estimated risk of calf DVT of 40-80%
without prophylaxis, with clinical PE occurring in 410% and fatal PE in 0.2-5%. Successful prevention
strategies include LMWH, fondaparinux, and
coumarins (INR 2-3). Dose-adjusted LDUH or LMWH
may be used with or without IPC/GCS.

LIFE STYLE MODIFICATION
A. Avoid obesity and inactivity
Avoid excess calories
Exercise (problem we should solute )
B. Avoid dehydration
Water, avoid alcohol
C. Avoid smoking
D. Maintain normal blood pressure
<120/80
MECHANICHAL METHODS

Intermittent Pneumatic Compression (IPC)
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Compression stocking.
Intermittent Pneumatic Compression (IPC)
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Consist of garment which
is fitted to the calf or
foot and inflated by a
pump .
Act by intermittent air
pumping thus preventing
blood stasis.
Also breaks down some
proteins in the blood that
can cause clotting.
IPC
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Ideal for immobilized patients, either in hospital,
skilled nursing facility, or at home.
Device is better tolerated when combined with 10to 18-mm Hg vascular compression stockings.
Some devices have “cooling buttons” to enhance
comfort.
Complications of IPC
1.
2.
3.
Discomfort warmth, and sweating beneath the vinyl
leg sleeves.
Peroneal nerve palsy and pressure necrosis of the
thigh with sequential type.
Compartment syndrome.
Compression stockings

Compression stockings are
specialized hosiery designed
to help prevent the
occurrence of and guard
against further progression
of venous disorders such
as edema, phlebitis and thrombosis.
Compression stocking


Compression stockings are elastic garments worn
around the leg compressing the limb, exerting
pressure against the legs reducing the diameter of
distended veins causing an increase in venous blood
flow velocity and valve effectiveness.
Compression therapy helps decrease venous
pressure, prevents venous stasis and impairs of
venous walls, and relieves heavy and aching legs.
Compression stocking
Indications for use :
 Deep Vein Thrombosis .
 Edema : When blood and/or tissue fluid pool in the
legs and feet due to poor circulation.
 Varicose veins : Saccular and distended veins which
can expand considerably and may cause painful
venous inflammation.
 Phlebitis : Inflammation and clotting in a vein, most
often a leg vein, due to infection, inflammation, or
trauma .
Compression stocking

1.
2.
3.
4.
5.
Contraindication :
Advanced peripheral obstructive arterial disease .
Congestive heart failure .
Septic phlebitis .
Oozing dermatitis .
Advanced peripheral neuropathy .
Inferior vena cava filter
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
Inferior vena cava filters were developed in an
attempt to trap emboli and minimize venous stasis. In
most patients with DVT, prophylaxis against the
potentially fatal passage of thrombus from the lower
extremity or pelvic vein to the pulmonary circulation
is adequately accomplished with anticoagulation.
An inferior vena cava filter is a mechanical barrier
to the flow of emboli larger than 4 mm.
Inferior vena cava filter
Temporary or removable filters, all of which may
also be left as permanent, permit transient
mechanical PE prophylaxis, this option may be
useful in the setting of:
polytrauma, head injury, hemorrhagic stroke, known
VTE, or major surgery when PE prophylaxis must be
maintained during a short-term contraindication to
anticoagulation.

Inferior vena cava filter
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In a randomized trial, the addition of an inferior vena
cava filter to anticoagulation for DVT increased the
risk of recurrent DVT (11.6% to 20.8%) and did not
improve the 2-year survival rate.
However, the filter group had significantly fewer PEs
(1.1% vs 4.8%). Of note was the risk of major
bleeding at 3 months (10.5%).
In the elderly patient with an increased risk of
bleeding, and particularly if the patient is at risk for
trauma, the risk and benefits may favor use of a filter.
Inferior vena cava filter


The ideal vena cava filter would trap venous emboli
while maintaining normal venous flow.
Many different filter configurations have been used, but
the current benchmark remains the Greenfield filter
with the longest long-term data. Patency rates greater
than 95% and recurrent embolism rates of less than
5%. The conical shape allows central filling of emboli
while allowing blood on the periphery to flow freely.
Numerous other filters with similar track records have
since been developed, including filters that can be
removed.
Inferior vena cava filters
IVC filter as it appear on X-ray
Greenfield filter
Inferior vena cava filter
American Heart Association recommendations for
inferior vena cava filters include the following[10] :
1.
Confirmed acute proximal DVT or acute PE in
patient with contraindication for anticoagulation
(this remains the most common indication for
inferior vena cava filter placement),
2.
Recurrent thromboembolism while on
anticoagulation,
3.
Active bleeding complications requiring
termination of anticoagulation therapy.
Prevention of
DVT

Awareness is the best way for prevention.

OUR RULE SO BE AWARE !
Done by:
Hisham sweidan
Emad tanni
Gaith al omary
Mohammad talafheh
Ahmad alawashreh
THANK YOU