Calf swelling Flashcards
Which 3 investigations are relevant for the diagnosis of a DVT
Remember this is not PE, so CTPA is not the correct answer.
D dimer and venometry (automated strain gauge plethysmography) are sensitive but not specific for the diagnosis of DVT.
A doppler ultrasound uses reflected sound waves to evaluate blood as it flows through a vessel. It is more specific for the diagnosis of DVT
In which cases might a D dimer be raised other than in a DVT
D-dimer is a sensitive, but non-specific test for DVT. It may also be increased in infection, pregnancy, malignancy and post-operatively.
What is the standard community management of DVT
Out-patient management of DVT is standard practice initially with:
- Subcutaneous low molecular weight heparin (IM) +
- Anticoagulation with warfarin orally or NOAC anticoagulants e.g. Rivaroxaban or Apixiban.
The dose of heparin is given according to what.
And when should heparin be used with caution and why
The dose of low molecular weight heparin depends on the patient’s weight in kilograms.
Low molecular weight heparin should be used with caution in severe renal failure due to increased risk of bleeding.
The following tests test for what:
INR APTT Thrombin Time Bleeding time Coomb's test
INR= Prothrombin time. The prothrombin time is used to measure the effect of warfarin, ratio to normal expressed as the INR (international normalised ratio).
APTT: Heparin is monitored using the APTT
Thrombin time: thrombin time measures fibrinogen function
Bleeding time: Tests platelet function
Coomb’s test: antiglobulin test used in autoimmune haemolytic anaemia.
What is the correct INR for uncomplicated DVT?
How long does the treatment typically last
INR 2.0-3.0
Treatment for an uncomplicated first DVT usually lasts between 6 and 12 weeks.
We aim for INR of 2-3 in patients who have had an uncomplicated DVT. Would an INR of 1.5 be even better if we could get it that low?
Incorrect. This is too low when treating DVT patients
In which patients would we use warfarin and aim for an INR or 3.5-4.5
This value is too high for DVT patients but may be used in patients with a prosthetic heart value.
What symptom might point to septic arthritis of a joint as a reason for calf swelling
Patients with septic arthritis will tell you that movement of the affected joint brings on excruciating pain in the joint.
What symptom might point to compartment syndrome of a joint as a reason for calf swelling
Patients with compartment syndrome in
their calf will tell you that moving the ankles and toes brings on pain in their
calf (as this causes the flexors of the foot to move within the compressed
compartment of the calf ).
What duration of immobilisation due to long distance travel is associated with increase DVT risk
ncreased risk of venous
thrombosis in people who are immobilized through travelling for more than
8 hours non-stop.
what matters is the prolonged
immobility, and not the type of transport used
Thus, most lay people will
(wrongly) associate DVTs with all forms of fl ying (irrespective of duration)
whilst few people will consider long-haul bus, train, or car journeys as a
risk for DVT.
Long distance travel increases risk of DVT in people with no other risk factors for DVT
F.
It is important to note that most studies suggest that the
increased risk of DVT associated with long-distance journeys applies only to
people with other predisposing risk factors for DVT, although patients may
not be aware of these at the time of travelling.
Oestrogen related risk factors for DVT include?
contraceptive pills in fertile women,
hormone replacement therapy for menopausal women,
tamoxifen in breast cancer patients
it is important to note that most people taking oestrogen/progesterone-based medications will have a low baseline risk of venous
thrombosis, and so increasing that risk only moderately will still result in a risk
that is low overall.
Leg swelling + lymphadenopathy
check for swollen lymph nodes along the aff ected leg and
in the inguinal fold, as lymphadenopathy would be highly suggestive of an
infection in the limb.
Leg swelling + abdominal mass?
an abdominal mass in the right lower quadrant would
suggest a tumour that could be compressing the right iliac vein
(ovarian)
