Miscellaneous1 Flashcards
Preop workup prior to vascular access
eval veins and arteries with duplex, arteriograms and venograms
Should vascular access start more distally or proximally
distally
What is the most distal fistula
radio-cephalic (Bescia-Cimino-Appel fistula)
What fistula can be created if a radio-cephalic fails
brachial-cephalic or brachial-basilic
What should be used if a patient does not have an autologous vein to use in a fistula
use a graft
What type of graft is best placed in the lower arm
loop-graft from brachial artery to cephalic vein
MC complication of vascular access
thrombosis
If thrombosis occurs post op from a fistula where is it MC found
proximal vein
Tx for post op thrombosis in new fistula
endovascular repair, angioplasty or stent
Organisms MC cultured from vascular access
Staph aureus, MRSA
Complications of vascular access
infection, seroma, aneurysms, pseudoaneurysms, proximal vein occlusion due to central vein stenosis, bleeding
What syndrome can iliac vein obstruction lead to
May-Thurner syndrome
Primary tx for VTE
systemic anticoagulation
Why is systemic VTE important
reduces risk of PE, extension of thrombosis and recurrence of thrombosis
What is the recommendation after a second episode of VTE or unprovoked VTE
prolonged warfarin
When is catheter directed thrombolysis accepted when used for VTE
axillary and subclavian VTE�s
What does May-Thurner syndrome put a patient at risk for
VTE
Descrive May Thurner syndrome
iliac vein obstruction leading to leg edema
Name 2 classes of agents for VTE treatment for oral therapy
direct thrombin inhibitors and direct factor Xa inhibitors
How is Rivaroxiban (anti-factor Xa) excreted
renally
Primary indications for IVC filter
complication of anticoagulation, contraindication to anticoagulation and or failure of anticoagulation
Indications for suprarenal IVC filter placement
IVC clot, pregnancy, women of childbearing age, previous filter clotted, previous filter that failed
Complications of IVC filter
migration, device failure: recurrent PE, fracture
How is an IVC with acute thrombus treated
full anticoagulation with heparin followed by catheter directed thrombolysis
Common tx for uncomplicated VTE
LMWH with transition to vitamin K antagonist for 3 months
When is aggressive thrombus removal considered in VTE
iliofemoral DVT and effort thrombosis and for those with PE and significant right heart strain
Etiology of sx�s of a PE
- obstruction of pulmonary arteries leading to decreased oxygenation and right heart strain 2. platelet activation the pulmonary circulation, with inherent release of vasospastic and bronchospastic substances
Initial workup of a PE
ECG, ABG, CXR
What are the findings on EKG for PE
right heart strain, S wave in lead I, Q wave in lead III and T waves in leads III VI and V3
3 occasional findings on CXR to indicate PE
Hampton hump and Westermark sign and Fleischer knuckle sign
Define Hamptons hump
CXR finding indicative of PE: : peripheral wedge shaped opacity at the costophrenic angle representing a pulmonary infract
Define Westermark sign
CXR finding indicative of PE: an area of focal ishcemia
Define Fleischer knuckle sign
CXR finding indicative of PE: enlargement of the central pulmonary artery
What does a positive VQ scan show with PE
wedge shaped perfusion defect with normal ventilation
What does a negative VQ scan mean with PE
exclude the diagnosis of PE
Modality of choice for detecting a DVT
venous duplex US
Describe a patient at low risk for DVT
minor surgery under 40yo, no additional risk factors
Describe a patient at moderate risk for DVT
minor surgery, 40-60yo, no additional risk factors
Describe a patient at high risk for DVT
patients older than 60, 40-60yo with additional risk factors (prior DVT, prior PE, cancer, hypercoagulability)
What stops propagation of the thrombus
anticoagulation
Indication for Vena Cava Filters
venous thromboembolism with contraindication to or failure of therapeutic anticoagulation, free floating thrombus in the IVC or iliac veins, critically ill patients with limited cardiopulmonary reserves
When should suprarenal IVC filters be considered
women of childbearing age, those with an inadequate �landing zone� in the infrarenal position
Criteria vena cava filter retrieval
PE has returned to an acceptably low level or that the patient can be therapeutically anticoagulated, life expectancy more than 6 months, any filter that has migrated, fractured or tilted
What causes lymphedema
lymphatic dysfunction that results in accumulation of protein rich fluid in the interstitium of extremities or other regions
What reactions occur secondary to protein stasis
inflammatory response with macrophages and fibroblasts replacing elastic interstitium with fibrosclerotic thickened congested tissue
What condition can arise from chronic lymphedema
Stewart-Treves syndrome: aggressive lymphangiosarcoma
Name primary etiologies of lymphedema (congenital)
Milroy disease, Meigs disease, Tarda
Describe Milroy disease
lymphedema that presents within the first 2 years of life: affects females moreso, bilateral LE edema, not progressive and may spontaneously resolve
Describe lymphedema praecox or Meigs disease
presents at puberty (before at 35), affects females, unilateral lower extremity involvement
Describe lymphedema tarda
presents spontaneously after the age of 35, rarest form
What are causes of secondary lymphedema
Wuchereria bancrofti, post-operatively
How is lymphedema diagnosed
lymphangioscintigraphy
Describe conservative management of lymphedema
hygiene, compression, elevation, physical therapy and diuretics
Name the surgical treatments for lymphedema
debulking, liposuction, shunt, Charles or Sistrunk procedure
Describe the Charles procedure
remove the tissue to the fascia and then perform a skin gift
Describe the Sistrunk procedure
staged excision of sub-Q tissues with incorporation of dermal and skin flaps
