Download Thrombophlebitis and Occlusive Arterial Disease

Thrombophlebitis and Occlusive
Arterial Disease
October 6th, 2005
George Filiadis D.O.
Thrombophlebitis
• Formation of a venous clot depends on the
presence of of at least of one of Virchow’s
triad factors
-venous stasis
-injury to vessel wall
-hypercoagulable state
Clinical risk factors for deep vein
thrombosis
• Trauma, travel
• Hypercoagulable,
hormone replacement
• Recreational drugs(IV
drugs)
• Old (age >60y)
• Malignancy
• Birth control, blood
group A
• Obesity, obstetrics
• Surgery, smoking
• Immobilization
• Sickness
Pathophysiology
• Most common cause of hereditary hemophilia is
factor V Leiden
• See Table 59.2 for other hypercoagulable states
• Thrombi usually form at the venous cusps of deep
veins where altered or static blood flow causes
clot formation
• Alternatively, clots form from intimal defects
• Clots are composed from fibrin, red cells and
platelets and cause partial/complete obstruction of
vein
Pathophysiology
• Postphlebitic syndrome (PPS) may develop
after the resolution of a DVT
• PPS is due valvular incompetence,
persistent outflow obstruction and abnormal
microcirculation.
Superficial Thrombophlebitis
• Thrombosis can occur in any superficial vein
primarily the saphenous vein and its tributaries
• Local pain, redness, and tenderness are
characteristic findings.
• Mild cases can be treated with warm compresses,
analgesia and elastic supports
• Severe cases can be debilitating and should be
managed by bed rest, elevation of extremity,
support stockings, and analgesia.
• Antibiotics and anticoagulants are useful in septic
thrombophlebitis
Superficial Thrombophlebitis
• Incidence of DVT from extension of a
superficial clot is 3%.
• Most clots in great saphenous vein will
extend into a deep vein system in a week or
so thus a follow-up US is guaranteed
• Definite treatment is ligation and excision
of affected vein.
Deep Vein Thrombosis
• Clinical exam is unreliable for detection or
exclusion of a DVT
• Pain, redness, swelling, and warmth are present in
less than half the patients with confirmed DVT.
• Pain in calf with dorsiflexion of ankle with the leg
straight (Homan’s sign) is unreliable
• See table 59.3 for predictors of deep vein
thrombosis
Deep Vein Thrombosis
• Symptomatic DVT will be in popliteal or more
proximal veins more than 80%
• Nonextending calf DVT rarely cause PE
• Uncommon presentations of DVT include
phlegmasia cerulea dollens and phlegmasia alba
dollens
• In phlegmasia cerulea dollens, patients present
with extensive swollen and cyanotic leg due to
massive ileofemoral thrombosis which can lead to
venous gangrene.
Deep Vein Thrombosis
• In phlegmasia alba dolens, the leg is white due to
arterial spasm secondary to massive iliofemoral
thrombosis, often mistaken for arterial occlusion.
• PPS can be difficult to differentiate from recurrent
DVT due to pain, swelling and ulceration of the
skin.
• Up to to one third of the patients with DVT can
develop PPS.
Deep Vein Thrombosis-Diagnosis
• All patients with any signs or symptoms
suggestive DVT should undergo an
objective diagnostic evaluation
• Venography was the historical “gold
standard” for detection of DVT with 100%
sensitivity and specificity but it is invasive
and can cause contrast-related reactions,
phlebitis and DVT (3%).
Deep Vein Thrombosis-Diagnosis
• Choice of test to identify DVT is ultrasound
• Ultrasound has 97% and 94% sensitivity and
specificity respectively for detecting proximal
DVT
• Ultrasound is less sensitive for pelvic DVT and
has sensitivity of 73% for a calf DVT.
• Impedance plethysmography is portable and
inexpensive but less sensitive than US
• IP measures changes in electrical resistance in
response to changes in calf volume due to
obstruction
Deep vein thrombosis-Diagnosis
• Radioisotopes have been used to diagnose DVT
but are not particularly useful in ED
• MRI is being used with increased frequency and
can detect a filling defect in entire extremity
(including calf and pelvic veins)
• D-Dimer fragments which are degradation
products of fibrin can be used to as an indicator
for the presence or absence of DVT or PE.
• The ELISA based D-Dimer has sensitivity 97 %
and specificity 35%
Deep Vein Thrombosis-Diagnosis
• When D-Dimer is less than 500ng/ml, the
likelihood of DVT is less than 1%.
• The latex agglutination assay D-Dimer is less
sensitive than the ELISA essay.
• Sepsis, surgery, trauma, hemorrhage, pregnancy,
cardiovascular diseases, collagen vascular disease,
liver disease, cancer are associated with elevated
d-dimer value.
Clinical Approach to Establishing
the Diagnosis
Treatment
• Bed rest, leg elevation and elastic stockings are of
unproven benefit in the management of DVT.
• Aggressive anticoagulation will prevent extension
of the clot.
• Early ambulation after adequate anticoagulation is
a safe approach
• Primary objective of treating DVT is the
prevention of pulmonary embolus
Treatment
• Patients with negative ultrasound can safely
have a repeat ultrasound in a week without
anticoagulation
• Risk of PE in these patients is near 0% and
risk of forming a DVT is 1%.
• Anticoagulation is recommended for
patients with calf DVT who had PE/DVT,
immobile, have hypercoagulable state
Treatment
• Patients with proximal DVT require
anticoagulation
• Preferred treatment is LMWH over UFH because
of the ease of administration, more predictable
anticoagulant effect, lack of need to monitor the
anticoagulation effect, lower incidence of major
bleeding and HIT
• LMWH has a preferentially inhibitory effect on
factor Xa.
Treatment
• Because of LMWH is cleared by the kidneys, it
should be avoided in outpatients with Cr >2.03
• One need not to wait for the creatinine result
before initiating LMWH therapy.
• The ability to discharge patients from the ED after
initial dose of LMWH is cost-effective, safe,
practical and acceptable practice as long as there is
a secured 24 hr follow up with PCP.
Treatment
• Indications for admission include inability
to ambulate, poor social support, unreliable
follow-up, difficulty with education with
drug administration, need for lysis or
invasive therapy, and an alternative serious
diagnosis under investigation or that
requires treatment(arterial ischemia,
cellulitis, pelvic mass)
Treatment
• If LMWH is contraindicated, use UFH as 80
units/kg bolus and then 18 units/kg/hr
• Serious bleeding from LMWH cannot be
completely reversed with protamine which has
been associated with hypotension and
anaphylactoid reactions.
• If a patient has contraindication to heparin like in
pt with HIT, you can use a thrombin inhibitor like
lepirudin
Treatment
• In pregnant pt who cannot have heparin, danaproid
should be used.
• It is acceptable to start coumadin and LMWH
simultaneously.
• Warfarin is contraindicated in pregnancy, active
bleeding, recent major surgery (thoracoabdominal,
nervous system, spine, eye)
• LMWH does not interfere with the work up of a
possible hypercoagulable state compared with
UFH.
Treatment
• Initial hematological testing at follow-up
includes factor V leiden, prothrombin
molecular tests, screening for
antiphospholipid anticoagulants and a
fasting homocysteine level.
• Upon completion of the anticoagulation ,
further testing includes antithrombin III,
protein C, protein S, and factor VIII level
Treatment
• Thrombolysis for DVT is indicated for
extensive iliofemoral thrombosis and upper
extremity DVT in patients with low risk for
bleeding.
• IVC filter is indicated for when
anticoagulation therapy is contraindicated,
there is embolization of DVT after 1-2
weeks of anticoagulation
Treatment
• Thrombectomy is only indicated with ischemic leg
secondary to a massive venous clot like in
phlegmasia cerulea dolens.
• In ED , pt adequately anticoagulated who present
with new thrombus or propagation should receive
LMWH
• If the fail LMWH or there is a free-floating
thrombus an IVC should emergently inserted.
Pelvic Vein Thrombosis
• Usually it’s an extension of a clot from the
femoral vein.
• An isolated pelvic vein thrombosis is rare and can
be a complication in the postpartum period, after
pelvic surgery or trauma.
• Septic pelvic vein thrombophlebitis is a lifethreatening condition after post-partum
endometritis and is usually diagnosed with CT or
MRI.
Axillary and Subclavian Vein
thrombosis
• 2-4% of DVTs occur in axillary or subclavian vein
• Risks include recent central venous catheters or
pacemakers, IV drug use, malignancy,
hypercoagulable states and excessive or unusual
exercise, chronic compression(cervical rib, scalene
or web)
• PE occurs in 5-10% of cases involving axillary or
subclavian DVT
• Treatment includes anticoagulation alone or
preceded by thrombolysis.
OCCLUSIVE ARTERIAL
DISEASE
• Acute limb ischemia secondary to thrombosis or
embolus is true emergency.
• Mortality is 25% and risk of amputation is 20%.
• 11-27%of elderly have peripheral arterial disease
• Smoking, diabetes, hyperlipidemia, hypertension
and homocysteinemia are significant risk factors
• At least half of the patients with coronary or
cerebrovascular disease have PVD
Pathophysiology
• Acute limb ischemia leads to cell death and
irreversible tissue damage.
• After prolonged arterial obstruction, reperfusion
may not be fully attainable due to distal edema and
thrombi forming in the microcirculation.
• Peripheral nerves and skeletal muscle are very
sensitive to ischemia and irreversible damage can
occur within 6 h of anoxia
• Non-embolic ischemia is due to atherosclerosis of
the vessels
Pathophysiology
• Progression of ischemic injury can occur
through several mechanisms:
i)propagation of clot to include collateral
vessels
ii)ischemia-related distal edema leading
to high compartment pressures
iii)fragmentation of clot in the
microcirculation
iv)edema of the microvasculature cells
Etiology
• Thrombotic occlusion is significantly more
common cause of acute limb ischemia than is
embolism.
• Emboli originate from the heart in 80-90 % with
atrial fibrillation being the cause in two thirds of
all peripheral emboli.
• Mural thrombus in the ventricle after recent
myocardial infarction is the second most common
cause.
Etiology
• Other causes of emboli include atrial myxomas,
vegetations from valve leaflets, and parts of
prosthetic devices such as mechanical valves.
• Noncardiac causes include thrombi from
aneurysms and atheromatous plaques.
• Iatrogenic embolization can happen during
angiograhic procedures of the aorta and larger
vessels
Etiology
• Thrombosis unrelated to atherosclerotic disease
can occur at an area of vessel injury during
invasive studies.
• Peripheral arterial supply can be obstructed by
vasospastic or inflammatory conditions like
Raynaud disease and Thromboangitiis obliterans
(young smokers)
• Limb ischemia can also seen with central causes
like thoracic aortic dissection and Takayasu
arteritis.
Etiology
• Low cardiac output states like cardiogenic
or hypovolemic shock may also present
with limb ischemia
• Cardiac tamponade, ischemic
cardiomyopathy, valvular heart disease can
impair left ventricle function and lead to leg
ischemia in patients with existing peripheral
vascular disease.
Clinical features
• 6 Ps:pain, pallor, polar (for cold), pulselessness,
paresthesias, and paralysis.
• Despite the belief that the limb salvage is possible
within 4-6h, tissue loss can occur with
significantly shorter occlusion times.
• Chronic peripheral arterial insufficiency is
characterized by intermittent claudication with
activity that is relieved at rest.
• Shiny, hyperpigmented skin with hair loss and
ulceration, thickenend nails, poor pulses are
hallmarks of chronic disease
Diagnosis
• Clinical evaluation is the most useful diagnostic
tool.
• Capillary refill is not reliable alone
• A hand –held Doppler can detect the presence or
absence of a pulse.
• If a pulse is detected, then the ankle-brachial index
(ABI) and segmental leg pressures should be
checked
• An ABI<0.5 indicates acute arterial obstruction
• If time permits, do a duplex ultrasound
Treatment
• Goals of therapy include restoration of blood flow,
preservation of limb and life, and prevention of
recurrent thrombosis
• Current practice includes UFH to prevent clot
extension, venous thrombosis, the appearance of
thrombi distal to the obstruction, and reocclusion.
• Fluid resuscitation and treatment of heart failure
and dysrhythmias are sometimes necessary to
improve limb perfusion.
• Definite treatment includes surgery or
thrombolysis
Upper Extremity Ischemia
• Upper extremity arterial occlusion is less
common.
• There is a well-developed collateral circulation
around the shoulder and elbow, thus arterial
occlusion is better tolerated.
• Usual causes are vasospasm, arteritis, trauma,
hypercoagulable state, plaque rupture, thoracic
outlet syndrome, aneurysms.
• Treatment includes heparinization and surgical
thrombectomy.
Aneurysms of the extremity
• Incidence of aneurysms in lower extremities
appears to be increasing due to the aging
population.
• Femoral and popliteal aneurysms are the most
common.
• Symptoms include local pain, limb edema, and
ischemic complications
• For femoral aneurysms (majority are false), US,
CT or MRI can confirm the diagnosis
Aneurysms of the extremity
In patients with popliteal aneurysm there is 37%
chance of abdominal aortic aneurysm and 50 %
chance of coexisting popliteal aneurysm on the
contralateral leg.
Subclavian artery aneurysms can produce central
neurologic findings or upper extremity iscemia
and are due to atherosclerosis, trauma, thoracic
outlet obstruction, syphilis or cystic medial
necrosis.
Questions
• 1.Regarding superficial thrombophlebitis, all of
the following are correct except:
• A)treatment includes bedrest, elevation, support
stockings, and analgesia.
• B)antibiotics and anticoagulants are of no proven
benefit.
• C)incidence of DVT from superficial thrombus is
30%
• D)all of the IV drug users with superficial DVT
should receive antibiotics
Questions
• 2.T/F Calf DVT usually extend proximally
and are a common case of PE
• 3.T/F Occlusive arterial disease is usually
due to a thrombosis event rather than
embolic
• 4. T/F Pt with political aneurysm frequently
have abdominal aortic aneurysm and contra
lateral political aneurysm.
Questions
• 5.Which of the following statements is true
• A)Diagnosis of a DVT can be based on clinical
exam
• B)Test of choice for diagnosis of DVT is
ultrasound.
• C)Venography is the gold standard diagnostic
modality given its low complications rate
• D)Ultrasound has higher sensitivity for detecting
calf DVT than proximal DVT
• Answers: 1)c, 2)F, 3)T, 4)T, 5)B