Haematology Flashcards
In regard to DVTs which one of the following is correct?
a) A negative d-dimer rules out a DVT
b) Ultrasound is only 70-75% sensitive for a calf DVT
c) Warfarin can be started without any other treatment in confirmed cases.
d) The dose of rivaroxaban is 15mg BID for 21 days and then 15mg daily for the remainder of the treatment.
e) The dose of apixaban is 10mg BID for the first 7 days and then 10mg daily for the remainder of the treatment.
B.
It is important to risk stratify DVTs, low risk and a negative D-dimer rules out a DVT. Moderate and high risk requires further investigation.
Ultrasound is only about 73% sensitive for calf DVT therefore if there is moderate to high risk a repeat ultrasound is advised in 5-7 days to rule out DVT.
Warfarin requires bridging with a LMWH.
Rivaroxaban dosing is 15mg BID for 21 days and then 20mg daily.
Apixaban dosing is 10mg BID for 7 days and then 5mg daily.
Which of these are a risk factor on the Well’s criteria for DVT?
a) Previous cancer
b) Calf swelling 2cm greater on symptomatic leg
c) Recent flight
d) Bedridden x 2d or more
e) Major surgery within 4 weeks
E.
Wells criteria:
1 point for:
Active cancer / paralysis, paresis or recent immobilisation of leg / recently bedridden x 3d or major surgery within 4 weeks / Local tenderness / Entire leg swollen / Calf swelling 3cm or greater on affected leg / Unilateral pitting oedema / Collateral superficial veins.
-2 points for:
Alternative diagnosis more likely
Score:
0 = Low probability
1-2 = Moderate probability
3+ = High probability
