URR Venous Thrombosis Flashcards
most common point of thrombosis origination
soleal sinuses of the calf
deep vein thrombosis usually originates where?
in the area of the valves
25% of calf vein thrombosis worsens and extends where?
into the pop V
what is aggressive treatment for deep vein thrombosis
-bedrest
-lovenox
-IV heparin
-coumadin therapy for 6-12 months after
what is may thurner syndrome?
-AKA iliac compression syndrome
-left leg DVT due to the left common iliac coursing under the right common iliac artery
-right CIA can cause extrinsic pressure on the left CIV, which can cause thrombus formation
reason for false positive results with CW?
-extrinsic compression closing the vein (bakers cyst, pelvic mass, pregnant uterus)
-significant arterial disease reducing inflow which reduces venous outflow
-improper angle of insonation (perpendicular to flow) causes no flow to be displayed
continuous flow in otherwise normal vein means what
prox obstruction
prox to a DVT, flow may be what?
very slow and visible on 2D imaging
-color doppler will demonstrate reduced or absent flow
if PW doppler flow pattern is detected with partial thrombosis, flow will be
continuous with no response to respiration/augmentation
what will veins looks like distal to an acute occlusive thrombosis
dilated and demonstrate continuous flow
-continuous flow in otherwise normal vein = prox obstruction
DVT in the deep system forces any remaining flow to other areas of lower pressure. Where does it go?
perforators
-flow exits the deep system through the perforators to try and “escape” into the patent superficial system
occlusive deep vein thrombus can lead to what kind of flow in the superficial system?
spontaneous continuous flow, if the GSV is the only outflow path for the venous blood, flow in the superficial system will increase
-if flow in the GSV of the unaffected leg is non-spontaneous and low velocity but the GSV of the affected leg demonstrates spontaneous continuous flow, this can indicated occlusive disease of affected leg
acute DVT most commonly occludes the vein with no
residual flow seen with color doppler
acute DVT is typically totally occlusive with no
flow detected on PW doppler
what is the rouleaux formation
RBCs appear lined up or stacked in rolls similar to coin rolls from your bank
rate this thrombosis:
-hypoechoic thrombus not totally occluding vein that is only partially compressible
-flow is able to move through vessel but loses the phasicity, more continuous
-recanalization can lead to the formation of a free floating tail of thrombus; patient will be placed on blood thinners or continue to take them to reduce the risk of embolism as the thrombus atrophies
partial thrombosis
rate this thrombosis:
-chronic swelling/edema, brown/blue discoloration, varicose veins, feeling of fullness or heaviness in legs, wet ulcer formation
-thrombus atrophies and fibrosis occurs
-adheres to vein wall causing fibrosis, rigidity and increased echogenicity
-vein is partially compressible with non-pliable thrombus within the lumen
-can cause valve damage (post-phlebitic syndrome)
-more echogenic than acute thrombus
-vein normal sized, not dilated like acute thrombosis
-doppler exam usually demonstrates continuous flow
chronic DVT
what is superficial phlebitis and thrombophlebitis
-inflammation of the vein walls w/o or w/ thrombus
-pain, swelling, reddening along affected vein
what is SVT
-thrombosis of the superficial vein of the lower extrem
-usually related to valvular insufficiency and/or patient inactivity
-may indicate DVT
-diagnosis usually made clinically
-painful, palpable cord
-treated less aggressively; anti-inflammatory drugs, support stockings, warm compress, limb elevation
-only 20% causes of thrombosis completely resolve, therefore chronic superficial thrombosis does occur
increased use of central venous catheters means what
increased UE DVT/SVT
facial swelling and chest wall varices can indicate what?
SVC thrombosis
how does acute thrombus look in UE
engorges vein, hypoechoic
chronic thrombus looks how in the UE
atrophied vein, hyperechoic
in the uppper extrem how is flow distal to thrombus
continuous
paget - schroetter syndrome
-AKA spontaneous effort thrombosis or venous thoracic outlet syndrome
-most common cause of axillary/subclav DVT in the ambulatory patient
-related to the presence of a cervical rib and thoracic outlet syndrome
-higher incidence in the dominant arm, related to repetitive motion
SVC syndrome
-progressive venous occlusion of the SVC
-malignancy primary cause
-causes dilitation of the veins in the upper extrem and neck
-IJV dilated bilat, may be visible especially when patient stands
-doppler demonstrates continuous flow in the bilat IJV
-treatement of the malignancy can reduce tumor size and symptoms of the SVC obsctruction
what is lemierre syndrome
-refers to thrombophlebitis of the jugular veins w/ oropharyngeal infection, such as pharyngitis/tonsilitis
-duplex eval can demonstrate thrombus w/in the jugular vein or other neck or facial veins
complications of extrem venous thrombosis?
-post phlebitic syndrome
-pulmonary embolism
-phlegmasia cerulea dolens
-phlegmasia alba dolens
what is post phlebitic syndrome
-DVT has resolved but damage to vein and valves has occured
-most common complication of DVT
-80% patients with DVT will develop insufficiency within 5-10 years
-DVT stretches veins, veins do not return to original shape, valves do not close properly causing reflux
-symptoms include tiredness and heaviness of the legs, swelling
what is a pulmonary embolism
-thrombus breaks loose and travels through the heart to the lungs
->90% PE come from lower extrem DVT
-most significant complication of DVT
-can be fatal
-pulmonary angiography preferred method of diagnosis
-V/Q scan (ventilation quotient or ventilation perfusion) is a nuclear medicine exam used to identify PE
what is phlegmasia cerulea Dolens?
-extensive thrombosis occluding deep system and superficial system
-markedly reduced arterial inflow caused by marked reduced venous outflow
-severe limb swelling, edema and mottled skin
-cyanosis occurs due to high concentration of deoxygenated blood
-ischemia in entire extrem very painful
-malignancy is the most common triggering factor
-can cause venous gangrene; involves foot and all toes (arterial gangrene usually involves one or two toes)
-usually treated with clot lysing drugs like streptokinase
what is phlegmasia alba dolens
-extensive thrombosis occluding deep system, but the superficial venous system remains patent
-causes mild reduction in arterial inflow
-acute onset of swelling, pallor, and pain
-swelling helps differentiate from an acute arterial occlusion
-pregnancy is the most common triggering factor
-usually treated with clot lysing drugs like streptokinase
differential diagnoses for DVT
-muscle strain
-leg injury
-muscle tear
-bakers cyst
-cellulitis
-lymphangitis
-heart failure
-extrinsic compression
-chronic insufficiency
-CHF
what is cellulitis
-common bacterial infection of the skin
-causes skin reddening and warmth in affected area
-edema can develop in response to the inflammation
-lymph nodes may enlarge in response to any type of infection
what is a bakers cyst?
-encapsulated synovial fluid collection in the medial pop fossa
-measure length, width, and height
-may have septations and or debris
-caused by chronic joint dysfunction
-gastrocnemius semimembranous bursa most commonly affected
-differential diagnoses include hematoma and abscess, patient hx becomes crucial to diagnosis
-can mimic partial thrombosis by causing continuous venous flow and limited augmentation response to pop vein
