DVT Flashcards
- Which of the following is the most common site affected by DVT?
a) Upper limbs
b) Lower limbs
c) Intracranial veins
d) Splanchnic veins - What is a life-threatening complication of DVT?
a) Pulmonary thromboembolism
b) Congestive cardiac failure
c) Myocardial infarction
d) Stroke - Which of the following is NOT a common risk factor for DVT?
a) Obesity
b) Smoking
c) Prolonged immobility
d) Regular exercise
- Answer: b) Lower limbs
- Answer: a) Pulmonary thromboembolism
- Answer: d) Regular exercise
Short Answer Questions
- What are the three main causes of DVT?
- What are the common symptoms of DVT?
2. Increased Viscosity of Blood
Causes :
Stagnation of blood in the vein,
increased viscosity of blood, and
inflammation of the blood vessel causing damage.
# 1. Stagnation of Blood in the Vein
Stagnation of blood in the vein, also known as venous stasis, occurs when blood flow through the veins is slowed down or stopped. This can happen due to various factors, such as:
- Prolonged immobility: Long periods of sitting or lying down, such as during long-haul flights, bed rest, or surgery, can cause blood to pool in the veins.
- Varicose veins: Enlarged or twisted veins can disrupt blood flow, leading to stagnation.
- Obstruction: Blood clots, tumors, or other blockages can restrict blood flow through the veins.
When blood stagnates in the vein, it can lead to the formation of blood clots, which can cause DVT.
Increased viscosity of blood, also known as hypercoagulability, occurs when the blood becomes thicker and more prone to clotting. This can happen due to various factors, such as:
- Dehydration: Inadequate fluid intake can cause blood to become thicker and more concentrated.
- Medications: Certain medications, such as birth control pills or hormone replacement therapy, can increase blood viscosity.
- Genetic disorders: Conditions like factor V Leiden or antithrombin deficiency can affect blood clotting and increase viscosity.
- Cancer: Some types of cancer, such as pancreatic or lung cancer, can increase blood viscosity.
When blood viscosity increases, it can lead to the formation of blood clots, which can cause DVT.
Inflammation of the blood vessel, also known as endothelial damage, occurs when the inner lining of the blood vessel becomes injured or inflamed. This can happen due to various factors, such as:
- Trauma: Physical injury, such as a car accident or fall, can damage blood vessels.
- Infection: Bacterial or viral infections, such as sepsis or endocarditis, can cause inflammation in blood vessels.
- Autoimmune disorders: Conditions like lupus or rheumatoid arthritis can cause inflammation in blood vessels.
- Surgery: Surgical procedures, especially those involving the veins, can cause endothelial damage.
When blood vessels become inflamed or damaged, it can disrupt blood flow and lead to the formation of blood clots, which can cause DVT.
In summary, the three main causes of DVT are stagnation of blood in the vein, increased viscosity of blood, and inflammation of the blood vessel causing damage. Understanding these causes can help healthcare providers identify individuals at risk of DVT and implement preventive measures.
Symptoms:
Swelling or firmness of affected limb,
pain in the affected limb, and
mild fever.
Essay Questions*
- Discuss the importance of establishing the DVT risk of patients and providing prophylactic treatment as necessary.
- Describe the common risk factors for DVT and explain how they contribute to the development of the condition.
- establishing the DVT risk of patients and providing prophylactic treatment as necessary is crucial for preventing this potentially life-threatening condition. By implementing effective DVT risk assessment and prophylactic treatment strategies, healthcare providers can improve patient outcomes, reduce healthcare costs, and enhance the quality of care.
- Common risk factors for DVT include
obesity,
smoking,
prolonged immobility (e.g. bed rest, long haul flights),
major surgery e.g. orthopaedic, abdominal and pelvic surgery,
pregnancy and the puerperium,
After caesarean section,
malignancies,
inherited blood disorders,
oestrogentherapy and
medicalconditions,e.g. congestive cardiac failure, myocardial infarction, nephrotic syndrome, stroke, systemic lupus erythematosus.
True or False Questions
- DVT can affect only the deep veins of the lower limbs.
- Anticoagulants should be used to treat DVT unless there are significant contraindications.
- Regular exercise is a common risk factor for DVT.
- False
- True
- False
Deep Vein Thrombosis (DVT) is a common disease although often—
asymptomatic
thrombosis may affect other sites, including:
Complications include
thrombosis may affect other sites, including the
upper limbs,
intracranial and
splanchnic veins
. Complications include:
pulmonary thromboembolism, which can be life-threatening
. It is therefore essential to have a reliable method for establishing the DVT risk of patients and to take active steps to provide prophylactic treatment as necessary.
Contraindications of anticoagulants in DVT
Contraindications to their use such as
recent intracerebral bleed,
severe liver disease,
active peptic ulcer,
bleeding disorders, and
severe hypertension.
Well’s Scoring for DVT probability
Well’s Scoring for DVT probability
The Well’s scoring system for DVT probability objectifies clinical suspicion of DVT risk and provides criteria for initiating treatment.
The presence or absence of the clinical features below are computed to give a pre-testing probability score for that particular patient which is used to priori- tise investigation and treatment.
y Paralysis, paresis or recent orthopedic casting of lower extremity (1 point) y Recently bedridden (more than 3 days) or major surgery within past 4
weeks (1 point)
y Localized tenderness in deep vein system (1 point)
y Swelling of entire leg (1 point)
y Calf swelling 3 cm greater than other leg (measured 10 cm below the tibial
tuberosity) (1 point)
y Pitting oedema greater in the symptomatic leg (1 point) y Collateral non varicose superficial veins (1 point)
y Active cancer or cancer treated within 6 months (1 point)
y Alternative diagnosis more likely than DVT (Baker’s cyst, cellulitis, muscle damage, superficial venous thrombosis, post phlebitic syndrome, inguinal lymphadenopathy, external venous compression) (-2 points)
Well’s Score Interpretation for DVT
Well’s Score Interpretation for DVT
3-8 Points: High probability of DVT
1-2 Points: Moderate probability
-2-0 Points: Low probability
Note
Low probability: D-Dimer test is recommended.
Low pre-test probability combined with a neg- ative D-Dimer test essentially rules out a DVT.
Moderate or High Probability: D-Dimer test with additional Doppler/compression ultra sound scan is recommended.
Investigations
Investigations
y D-Dimer test
y Doppler ultrasound
y Thrombophiliascreene.g.proteinC,proteinSlevels(inpatientswith
recurrent DVT) y FBC
Treatment objectives
Pharmacological treatment: 125
Treatment
Treatment objectives
y To prevent clot propagation and pulmonary embolism y To prevent recurrence
Non-pharmacological treatment
y Avoidance of prolonged recumbency and dehydration
y Avoidance of excess amounts of coffee, tea and alcohol, especially
on long journeys
y Increase water intake during long journeys or periods of immobility y Regularexerciseduringlongjourneyse.g.stoppingonroadjourneys
to take a walk or moving about on a plane during long flights and leg
flexing exercises while seated
y Avoid crossing legs for long periods on long journeys y Use of elastic compression stockings
