الفهرس 
Histology and surgical anatomy of the veins of the lower limbOnly 14 pages are availabe for public view
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Abstract
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.SUMMARY
The deep venous thrombosis develop most commonly
in the lower limb, mostly, in the left one, mostly, in the
.soleal venous sinuses. The upper Ijmb is almost immune from
post operative vein thrombosis, mostly due to .the speed at
which the blood flows in the upper limb; which is double
what is in the lower limb veins, therefore measures to
combat venous stasis in the lower.limbs ought to reduce the
risk of deep vein thrombosis.
The availabie methods of avoiding a thrombus in the
deep veins of the lower limbs and SUbsequent pulmonary
embolus after surgical operation are not successful.
The prevention of deep vein thrombosis by routinely
abolishing the power of the blood to clot throughout the
entire venous system at the body by giving anticoagulant
drugs is clumsy because the risk is Virtually confined to
the veins of the lower limbs. Morever, this method carries
a complication of its own as sponta~eous haemorrhage.
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The risk of deep vein thro.bosis which occurs while
the patient is undergoing the operation can be reduced by
routinely elevating thepatient’8 legs I5° above the horizontal;
or by routinely 8timulatin,~ the calf muscles by
galvanic current at an electrical :pressure of I20 volts and
a rate of 30 shock per minute. Ven’Jus stasis is avoided by
these measures.
from the most commonproph;rlactic measures against
occurrence of deep venous thrombos:ls, five methods are in
cOJlllJluosne: ’Aspirin” Low molecular weight dextran, Minidose
of,heparin, Bilateral intermittent pneumatic compression,
and Elastic compression stockings. Minidose heparin and
elastic stockings, gives good prophylaxis than heparin alone.
Also, intermittent pneumatic compretssion, gives a good
degree of prophylaxis as it was fOtlnd that beside, reducing
venous stasis, it also stimulates l’ibrinolysis.
Patients who are at very h:l,ghrisk of developing
venous thrombosis and embolisation in the post operative
period (Old ag~, Severe trauma ,orN:a;jorsU’rgery, Previous
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history ’of thromboembolism, and Ob,esity) should be given
prophylaxis by full .perioperative lanticoagulation. Patients
at very low risk (Child having lIin’Jr, o.peration), do not need
.pro.phylaxis.For the majority of s11rgioal .patients who fall
between these two extremes, the b,’nefits of .pro.phylaxis
remains in question.
” ,
A oarefull history and eX8I1linationshould be made
in all .patients with sym.ptoms and /ligns of acute venous
thrombosis to exclude other condi t:Lons. Less than 50 .per
cent with these signs and sym.ptoms have venous thrombosis.
It venogra.phy is the only objeotivE! test available; it should
be performed on all .patients with leg sym.ptoms and signs
oom.patible with venous thrombosis.
Clinical suspicion of VenO\;lSthrombosis can be
exoluded or confirmed by perform~: impedanoeplythesmogra.
phy alone or with fibrinogen leg scanning. If impedance
plythesmography is positive (in absenoe of conditions known
to .produce a false’positiveresults), a confident diagnosis
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of venous thrombosis~an be made w1d the patient treated
appropriately. If it is negative, -;he clinician has two
alternatives; Either to repeat it Or to do Iodine -I25-
fibrinogen soanning of the leg to deteot active venous
thrombosis. The use of impedance plythesmography alone is
,based on the supposition that calf vein thrombosis which
is not detected by impedanoe plythElsmography does not require
treatment ,unless it extends.,
• Primary prophylaxis ,using drugs or physical therapy
whioh are effective against deep venous thrombosis especially
of lower limb, which are the main source of emboli.
• Early detection of subclinioal venous thrombosis by
screening patients (e.g. postoperative leg scanning with
iodine -I25- fibrinogen) which provide the opportunity for
treating silent thrombosis early before they embolize.
Primary prophylaxis ,is likely to be the more effective and
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le.s expensive approaches.
Treatment ot venous thromb.)elDbolism, essentially
by antiooagulation; initially by h.,parin either by intermittent
intravenous heparin in a de).e ot 5000 I.U./ tour
hours r so.ooc I.U./ day), or cont:lJluousintravenous heparin
ad3usted to JDaintain partial throal)oplastin time between
1.5 and 2 time. the preheparin con1;rol value, and this is
pretered because. the interJDittent JLntravenoU8heparin therapy
is associated with higher risk otllleeding.
Heparin therapy should con1;inuedtor 7 - 10 days,
tor a.thrombus to adhere to the vej~ wall.
The initial heparin therapJ’ is tollo.ed by a long
terJDanticoagulant (oral) therapy, wartarin sodiUlllin a
dose ot 10 mgper day, atter 7 d~.lot heparin therapy,
and both drUgs are administered tOI?;etherfor at least 4 to 5
days. After initial dose ot wartarj~ the dose is adjusted
by monitoring prothrombin time at 1.25 times the control
value, and this regimen continued for at least 2 to J months.
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Fibrinolytio drugs as strep”tokinase and urokinase
are used to ensure lysis of thrombi and emboli, and restore
oirculation, but it has its ownoomJplioations and oontraindications.
Su~gioal interferenoe is l~nited to the special
oomplioated c•• es and includel’rranisposition of valves ,
Thrombectomy,and Inferior vena cay,al interruption.