DVT Mind-maps

Question 1

What is it

Answer 1

A clot that usually develops in one of the deep veins

Usually occurs in the leg

Question 2

Signs and symptoms

Answer 2

Asymptomatic
Pain
Oedema
Erythema/discolouration
Increased temperature of symptomatic leg
Engorgement of the surface veins

Question 3

What is Virchow’s triad

Answer 3

Hyper-coagulability
Endothelial injury/trauma
Stasis of blood flow

Question 4

Causes of hyper-coagulability

Answer 4

Malignancy
Surgery
Trauma
Oral contraceptive pill
Clotting abnormalities

Question 5

Causes of venous stasis

Answer 5

Immobility e.g. after surgery
Pregnancy
Heart failure

Question 6

Causes of endothelial trauma

Answer 6

Inflammation

Previous thrombosis

Question 7

Complications

Answer 7

Pulmonary embolism

Post-thrombotic syndrome

Question 8

Differential diagnosis

Answer 8

ABC:
A musculoskeletal injury
Baker’s cyst rupture
Cellulitis

Question 9

Investigations

Answer 9

D-dimer
B-mode venous compression ultrasonography (DVT ABOVE knee)
Investigations to uncover the cause of DVT
Modified Wells Score

Question 10

Is D-dimer test sensitive or specific

Answer 10

Sensitive but not specific

Question 11

What is meant by D-dimer test being sensitive but not specific

Answer 11

If the result is negative then the cause is unlikely to be DVT

Question 12

What is purpose of Modified Wells score

Answer 12

Calculate probability of DVT

Question 13

Treatment

Answer 13

Anticoagulation therapy:

Unfractionated heparin or a LMW Heparin

Question 14

Treatment: secondary management of DVT after anticoagulation therapy

Answer 14

Vitamin K antagonist e.g. warfarin

Question 15

Example of LMWH

Answer 15

Dalteparin

Question 16

What is meant by D-dimer test being sensitive but not specific

Answer 16

High Sensitivity: Out of those with the disease (TP + FN) most people will be told if they have the disease (lots of True Positives and low False Negatives)
Low Specificity: Out of those that do not have the disease (TN + FP), more people will falsely test positive to the disease (Low True Negatives and High False Positives)