Venous and Lymphatic Disease Flashcards
(16 cards)
Venous anatomy
- Veins are thin walled, collapsible, and highly distensible to a diameter sevreal times greater than that in the supine position
- the venous intima is composed of nonthrombogenic endothelium that produces endothelium derived relaxing factors such as nitric oxide and prostacyclin
- Venous valves close in response to CEPHALAD TO CAUDAD blood flow at a velocity of at least 30 cm/s
- The IVC, common iliac veins, portal venous system, and cranial sinuses are valveless
Chronic venous insufficiency
- Incompentence of venous valves, venous obstruction
- Eczema and dermatitis
- Lipodermatosclerosis
- WBC trappingg
- Hemosiderin deposition
The most common location of venous ulceration is approximately 3 cm proximal to the medial malleolus
Venous thromboembolisn
- Increased morbidity and mortality
- 6% DVT 12% PE
- Pulmonary hypertension
- Postrhrombotic syndrome
- Higher risk in future venous thromboembolism
Virchow triad
Stasis
Endothelial damage
Hypercoaguloiloty (most important is most cases of spotaneous VTE)
Risk factors for inherited VTE
- Factor V leiden
- Prothrombin20210A
- Antithrombin deficiency
- Protein C deficiency
- Protein S deficiency
- Factor XI elevation
- Dysfribrinogenemia
May-thurner syndrome is an anatomical factor associatted with icnreaed DVT formation and is characterized by
Narrowing of the left iliac vein at the site where the right iliac artery crosses over it
A caprini score of >5 in a general surgery aptient without thromboprophylaxis is associated with what percentage risk of developing a DVT?
6%
Phlegamsia cerulea dolens
Extensive DVT of the major axial deep venous channels of the lower extremity potentially complicated by venous grangrene and/or need for amputation
- Pain
- Pitting edema
- cyanosis
According to the American College of Chest Phsyicians, the recommended duration of long term antithrombotic therapy after provoked DVT is
3 months
Indication for Placement of IVC filters
- Bleeding complciation form anticoagualtion therapy of acute VTE
Recurrent DVT or PE despite adequate anticoagulation thearapy - Severe pulmonary hypertension
Appropriate theapies for suppurative thrombophlebitis
- NSAIDs
- Antibiotics
- Removal of existing indwelling venous catheters
- In patients with SVT not wothin 1 cm of the saphenofemoral junction
- compression and adminsitration of anti-inflammatory medications such as indomethacin
- SVT that extend proximally to within 1cm of the saphenofemoral junction
- extension to tje common femoral vein is more likely to occur
- anticoagulation for 6 weeks and great saphenos vein ligation appear equally effective
Sclerotherapy
can be successful in veins <3mm in diameter and in telangiectatic vessels. Sclerosing agents include hypertonic saline, sodium tetradecyl sulfate and polidocanol
- 11.7% to 23. 4% Hypertonic saline
- 0.125 to 0.250% sodium tetradecyl
- 0.5% polidocanol
Elastic bandage is wrapped around the leg after injection, and worn continuously dor 3 to 5 days. Compression stockings whould be worn for minimum of 2 weeks
Heparin induced thrombocytopenia
Results from heparin associated antiplatelet antibodies directed against platelet factor 4 complexed with heaprin
HIT is diagnosed based on previous exposure to heparin platelet count less than 100,000 and/or paltelt count decline of 50% following exposure
Direct thrombin inhibiting medications
Argatroban, hirudin, bivalirudin
- inhibits the conversion of fibrinogen to fibrin as well as thrombin induced platelet activation
- Reserved for
- patients in whom there is a high clinical suspicion or confirmation of HIT
- patients who have a history of HIT or test positive for heaprin associated antibodies
- Should be administerd for at least 7 days, or until the plt count normalizes
- Warfarin may then be introduced slowly, overlapping therapy with a DTI for atleast 5 days
Lymphedema
- Secondary lymphedema is more common
- Axilalry node dissection leading to lymphedema of the arm is the most common cause of secondary lymphedema in the US
- Filariasis and other environmetnal exposures (podoconiosis) are common cause of lymphedema globally
- Surgery is the mainstay therapy of lymphedema
- Lymphedema parecox - most common form of primary lymphedema
- women
- childhood and teenage years
- swelling of the foor and calf
- lymphedema tarda
- uncommon
- 35 years
Mesenteric Vein thrombosis is associated with
- 5 to 15 % cases of acute mesenteri ischemia occur as a result of MVT
- Patients with MVT are treated with fluid resuscitation, heaprin anticoagualtion, and bowel rest
- CT scan and MRI are 100% sensitive and 98% specific for MVT
- More common in patients with hypercoagulable states, malignancy and cirrhosis
