lower extremity venous disease and risk factors

Question 1

Virchow’s triad

Answer 1

stasis

intimal injury

hypercoagulability

Question 2

risk factors for thrombosis

Answer 2

Stasis: bed ridden (paralysis, surgery), elderly, obese, heart disease (CHF, MI, hypotension, COPD)

Trauma:  surgery, fractures, needle stick

Hypercoagulability: pregnancy, oral contraceptives (or estrogen intake), malignancy, myeloproliferative disorders, h/o DVT

Ask about grafts, bypass surgery, anticoagulant or lytic therapy

Question 3

types of venous disease

Answer 3

thrombosis and valve incompetence

Question 4

types of thrombosis

Answer 4

Acute
Chronic
Phlegmasia alba dolens
Phlegmasia cerulea dolens

Superficial thrombosis

Question 5

what types of valve incompetence are there?

Answer 5

Chronic

Varicose Veins: Primary, Secondary

Question 6

when does thrombosis generally occur?

Answer 6

ofter w/ secondary inflammation (thrombophlebitis) and when mechanisms of virchow’s triad are present

Question 7

signs and symptoms of acute disease

how reliable are clinical symptoms?

what do they entail?

Answer 7

less than 50% reliable

constant acute pain, increased with dependence relieved with elevation
  
Edema Erythema
respiratory distress (if emboli)
  
warm leg red streaks
Homan’s sign (pain with dorsiflexion)

Shortness of breath from pulmonary embolism

Question 8

pulmonary embolism

Answer 8

 Emboli from DVT travels to right atrium > right ventricle > pulmonary artery > lungs
 Should not get to left side of heart or systemic arterial circulation unless ASD

Question 9

what is the greatest acute, life threatening risk factor of DVT?

Answer 9

pulmonary embolism

Question 10

other causes for symptoms (acute disease) aside from pulmonary embolism…

Answer 10

Cellulitis

CHF

Baker’s cyst

Pop aneurysm

lymphadenopathy/ lymphangitis (lymphedema)

musculoskeletal injury

extrinsic compression

Question 11

chronic disease signs and symptoms

Answer 11

Pain

Chronic limb swelling (esp. ankle)

Hyperpigmentation

Venous ulcerations (can be treated w/ maggot therapy)

Question 12

what do this images show sequentially?

Answer 12

progression of venous disease

Question 13

phlegmasia alba dolens spectrum

what does this disease threaten?

what are its symptoms

Answer 13

Phlegmasia – heat; inflamation
Alba – white
Phlegmasia alba dolens (white leg, milk leg)

Limb threatening condition

Acute iliofemoral thrombosis
Distal arterial spasms with decreased pulses

Symptoms
Pallor, Swelling, usually without redness, Cool to touch, May follow parturition or acute febrile illness.

Question 14

phlegmasia cerulea dolens spectrum

Answer 14

Phlegmasia – heat; inflamation
Cerulea – blue (se –roo’le-a)
Phlegmasia cerulea dolens –blue phlebitis, blue leg

Limb threateing condition from severe extensive acute iliofemoral thrombosis

Results from severely reduced venous outflow, causing decreased arterial inflow

Acute fulminaing form of DVT

Symptoms: Cyanosis (bluish), Sudden pain, Massive edema, Venous gangrene (Cruveilhier), progression PCD to tissue necrosis

Question 15

how is superficial vein thrombosis diagnosed?

what is it characterized by?

Answer 15

clinically

warmth/local erythema

Localized thenderness

Palpable subcutaneous hard “cord”

Question 16

what is valvular incompetence?

what type of venous insufficiency does it represent?

What does it cause?

Answer 16

dysfuncitoning venous valves allowing reflux

chronic venous insufficiency

Varicose Veins:

Primary - insufficiency of superficial system only
No obvious cause of valve dysfunction
heredity, trauma, inflammation

Secondary - insufficiency of deep with secondary superficial disease.
AKA postthrombotic syndrome
previous DVT

Question 17

what does chronic venous insufficiiency affect?

what happens to folks w/ this?

Answer 17

More severe and effecting the deep venous system

Damaged or absent valves allow retrograde flow leading to venous hypertension
Calf muscle pump no longer workds
Often secondary to previous DVT that damage the valves (postthrombotic syndrome)

Progression to: Pitting edema or Ulcerations

Question 18

where do symptoms of chronic venous insufficiency usually appear?

what do they cause?

Answer 18

Symptoms usually on medial calf and ankle, less commonly lateral side (“Gator zone”)

Hyperpigmentation – “brawny discoloration”
Stasis dermatitis
Edema

Progression to: Pitting edema and Ulcerations

Question 19

what does this look like?

Answer 19

postthrombotic syndrome

Question 20

What zone are venous ulcerations generally in?

Answer 20

the “gator zone”

Brown or deep red
Shallow but wide
Irregular boarders

Question 21

venous ulceration etiology (theory)

Answer 21

1. Chronic increase in intraluminal pressure.
2. Increased vein wall permeability, plasma and fibrinogen leak out into surrounding tissue.
3. Fibrinogen converts to fibrin.
4. Barrier formation between capillaries and tissue,
   results in a decrease of O2 and nutrient delivery.
5. Subcutaneous bacteria invasion

Question 22

what is ambulatory venous hypertension?

what does the insufficiency result in?

What does it do to the calf pressure?

what does it cause?

Answer 22

Increase in venous pressure when person walks or stands

Insufficiency results in early refilling of venous pool after muscle contraction

Causes progressive and sustained increase in calf vein pressure

Causing: Edema, Varicosities or Ulcers

Question 23

What is the difference between primary and secondary varicose veins?

Answer 23

Primary: Superficial system only, unrelated to deep system

Caused by: Hereditary
Congenital absence of valves
Venous hypertension
Trauma
Inflammation

Secondary: Valve damage from previous DVT
Can result in incompetency of: Perforating veins, Superficial veins, Deep veins, Combination of all

Question 24

what could these be?

Answer 24

posterior calf varicosities

Question 25

what types of diagnostic testing are available?

Answer 25

Venography (angiography)  Isotope venography (Nuclear medicine)  Lung perfusion (nuclear medicine)  CT  MRI  Duplex  Plethysmography  d-Dimer assay

Question 26

venography (angiography) & its limitations

Answer 26

Once considered “gold standard”, not currently used  Limitations: Invasive, Venous assess may be difficult, Inadequate contrast filling

Question 27

what type of test is this? what does it look for?

Answer 27

Venograms Intraluminal thrombus, arrows  Calf collaterals

Question 28

May Thurner's Syndrom

Answer 28

Compression of left CIV by right CIA

Question 29

what type of test is a Nuc Med study demonstrates peripheral and pulmonary veins. Very sensitive to actively developing thrombus and calf thrombus. what are it's limitations?

Answer 29

isotope venography Limitations: cannot detect established thrombus sensitive to clinically insignificant thrombus 24 hours to do test

Question 30

what test detects pulmonary perfusion defects m/l from emboli? what are its limitations?

Answer 30

lung perfusion scan (VQ scan) many conditions can cause pulmonary emboli not specific to venous thrombus

Question 31

what does nuclear medicine look for?

Answer 31

evluation for PE, secondary to DVT

Question 32

what type of test shows cross section from pelvis into LE and can reconstruct images? what are this tests' limitations?

Answer 32

CT or MRI w/ contrast requires injections, more costly

Question 33

What type of noninvasive tests are available for venous insufficiency.

Answer 33

Duplex: 2D, Color Doppler, Spectral Pulsed wave Doppler Plethysmography: PPG, strain- gauge

Question 34

what type of blood (laboratory) tests are out there

Answer 34

d-Dimer  Prothrombin Time (PT)  Partial Thromboplastin time (PTT)  International Normalized Ratio (INR)  Platelet count  Fibrinogen

Question 35

what does the d-Dimer assay test for? What is elevated d-Dimer test mean? what other reasons would u see an elevated d-Dimer?

Answer 35

r/o active blood clot formation (Fragment D-dimer; Fibrin degradation fragment) Normal d-Dimer r/o possibility of active thrombotic formation Elevated d-Dimer abnormally high level of fibrin degradation products present BUT does not mean a blood clot is present JUST indicates that additional testing may be needed to look for a clot Other reasons for elevated d-Dimer: recent surgery, trauma, infection, liver disease, pregnancy, eclampsia, heart disease, and some cancers

Question 36

what blood tests evaluate: the ability of blood to clot properly the function of all coagulation factors, used to screen patients for any previously undetected bleeding problems prior to surgical procedures and monitor patients on anti-coagulant drugs (i.e. warfarin (Coumadin) and heparin)  What does a decrease in these times indicates

Answer 36

PT (prothrombin time) and PTT (partial thromboplastin time) increased risk for clotting

Question 37

what is the international normalized ratio (INR)? How has the World Health Organization addressed this system variability problem?

Answer 37

Calculate ratio used to standardize reporting of patient blood clotting properties INR = (patient PT/mean normal PT)ISI Normal INR is 2-3 Prothrombin Time (PT) is known to be very system-dependent 1. establishment of primary and secondary international reference preparations 2. development of a statistical model for the calibration of thromboplastins to derive the International Sensitivity Index (ISI) and the INR.

Question 38

what can platelet tests tell you?

Answer 38

platelet perform clotting functions  determination of the number of platelets present and/or their ability to function correctly

Question 39

what do fibrinogen tests tell you?

Answer 39

Fibrinogen is usually ordered with other blood clotting tests to evaluate ability to form a blood clot.

Question 40

what are ICD9 codes for venous exam?

Answer 40

Patient’s must have one of these symptoms or diagnosis to request the exam.  Exams performed without appropriate codes are subject to denial of payment by insurers.  Note the symptoms listed and think about the connection between these symptoms and LE venous disease.  Also note, an arterial and venous exam can not be ordered for the same day – these will not be reimbursed.

Question 41

when would a sonographic test of the LE venous system be ordered?

Answer 41

in cases of acute or chronic deep vein thrombosis

Question 42

what type of medical therapy is availabe for thrombus?

Answer 42

Controlling risk factors – limit bedrest, elastic stockings, elevation , pneumatic calf compression, Unna Boot for ulcers (medicated compression dressing  Anticoagulant therapy for prophylaxis – low dose heparin  Anticoagulant therapy for acute DVT or PE – loading dose of heparin to prevent propagation of thrombus (will not lyse the clot), oral anticoagulation (coumadin). PT and PTT monitored, regulated at 1.5-2 times normal. Treatment for 5-10 days. Patient remains on coumadin for 3-6 months.

Question 43

what type of surgery thrombosis is available for thrombus?

Answer 43

IVC filter (Greenfield or bird’s nest) with acute DVT in patients where anticoagulant therapy is contraindicated. Done via flouro  External IVC clip can be placed during surgical procedures  Thrombolytic therapy – streptokinase or urokinase to dissolve clot  Thrombectomy in cases of complete obstruction and possible limb loss from phlegmasia cerulea dolens (blue phlebitis), fulminating form of DVT with arterial spasm, pronounced edema, severe cyanosis, purpuric areas and petechiae

Question 44

what type of therapy is available for varicose veins?

Answer 44

Valvular reconstruction or transplantation for chronic insufficiency – uncommonly done  Ligation of incompetent superficial veins  Vein stripping or excision for varicosities  Percutaneous interventional therapy for varicosities  Sclerotherapy on small varicosities (sodium tetradecyl sulfate)

Question 45

what is the goal of an endovenous occlusion? how is this accomplished?

Answer 45

to permanantly collapse the vein. Accomplished via catheter placement, entering at approximately the knee and advanced to 1-2 cm below SFV.  Occlude the vein from proximal to distal.  Ultrasound required for pre-procedure evaluation, guidance during the procedure and post-procedure evaluation.

Question 46

what is this procedure?

Answer 46

venous ablation technique w/ ultrasound guidance. 2 - diagram of the radio freqency venous ablation

Question 47

what type of procedur sends out radiofrequency, a form of electrical energy, to heat the vessel wall causing collagen contraction. how do they acheive maximum heat?  what is used to stop clot formation?

Answer 47

endovenous radiofrequency closure device Must have physical contact with the wall, so the catheter has flexible, expandable electrodes. For maximum heating, blood flow must be stopped during the procedure. Compression at SFJ accomplishes this goal. Heparinized saline is infused to stop clot formation on the electrodes.

Question 48

what procedure is being done here?

Answer 48

US guidance and ablation