Week 9 - Lesson 2 (Part 1) Flashcards
What veins do we worry about the most?
Deep ones
What affects venous flow? (6)
- Respiratory variations
- Cardiac function
- Calf muscle pump
- Competent venous valves
- Venous pressure
- Exercise
Is DVT more common on men or women?
Women
What ethnicity is DVT more common in?
African Americans
What ethnicity is DVT least common in? (2)
- Asian
2. Native Americans
What are 5 hereditary risk factors of DVT?
- Blood disorders
- Antithrombin deficiencies
- Elevated clotting factors
- Plasminogen deficiency
- Prothrombotic disease
What are 8 acquired risk factors of DVT?
- Age
- Obesity
- Advanced malignancy
- Recent surgery
- Trauma
- Immobolization
- Pregnancy
- Oral contraceptive use
What is plasminogen suppose to do?
Break down clots
Why is pregnancy a risk factor? (2)
- Increase in estrogen
- leads to clot formation - Pressure from the baby
Where is the most common place for DVT?
In the calf at the valve leaflets
What are signs and symptoms for DVT? (3)
- Lower extremity swelling
- Pain
- Positive Homan’s sign
Positive Homan’s sign
Pain on forced dorsiflexion of foot
What is DVT also called?
The silent killer
Why do people with DVT feel pain?
Because its closer to the skin
What is virchows triad? (3)
- Endothelial damage
- Venous stasis
- Hypercoagulable state
What happens at the virchows triad?
Once the lining of the vein is not smooth anymore, this allows blood cells to adhere and coagulate here
What is a good example of a cause for clotting?
Trauma
D-Dimer assay
Measures fibrin degradation products that accumulate in the blood when thrombus forms
What is unlikely to occur when the D-Dimer test is negative?
DVT
What contributes to false positives for D-Dimer tests? (4)
- Patients who are over 80 years
- Hospitalized
- Pregnant
- Cancer
PT
Prothrombin time
Prothrombin time
Time it takes the plasma to clot
What is PT effected by?
Disseminated intravascular coagulation
DIC
Disseminated intravascular coagulation
PTT
Partial thromboplastin time
Partial thromboplastin time
Unexplained bleeding or clotting
What is PTT used for?
To evaluate hemostasis
Hemostasis
The process the body uses to form clots and to stop bleeding
How does acute thrombus look on US? (2)
- Faintly echogenic
- almost invisible - May have a long snakelike clot swaying back and forth in the lumen
How is acute thrombus detected?
Through limited compression and faint visible edge of clot
What are more dangerous acute or chronic clots?
Acute clots
Why are acute clots more dangerous?
Poorly attached clots can easily break off and cause a risk for an emboli
