48 - Venous Thromboembolism Flashcards
Initial recommendations for DVT?
- rest if symptoms warrant (reduces pain and swelling) but early walking is safe and may be preferred as resolution of pain and swelling may be faster
- elevate swollen limb while resting may increase resolution of edema
- start w acetaminophen (don’t increase bleed risk)
- opioids may be required short-term
Initial recommendations for PE?
- oxygen for hypoxia
- IV fluids if hypotensive or volume contracted
- vasopressors for hypotension or shock
- start w acetaminophen (don’t increase bleed risk)
- opioids may be required short-term
What is PTS (post-thrombotic syndrome)?
chronic swelling and pain, discomfort when walking, and skin discoloration
How do compression stockings help with PTS?
do not prevent PTS but they can improve edema and pain in the acute stage of DVT and can relieve pain of PTS
What is 1st line for established DVT or PE?
LMWH, UH, or fondaparinux
What needs to be used with your 1st line agents (LMWH, UH, or fondaparinux) in the beginning?
- oral vitamin K antagonists such as warfarin needs to be started at the same time and administered concurrently for several days
- Give your 1st line agent a min of 5 days or until the INH > 2 for 24-48 hours before stopping warfarin
What else can you use for Tx of VTE?
DOACs
How long do you treat for?
- Treat for 3 months if it was provoked or first episode of unprovoked distal DVT
- First unprovoked event = min of 3 months but can be longer
- Extended treatment if it’s related to cancer or 2nd episode of unprovoked VTE
The dose of UH is adjusted to prolong the aPTT to a time that corresponds to a heparin anti-Xa level of _____
0.3-0.7
When using warfarin, target what INR?
2-3
Do ASA and NSAIDs affect INR?
no but they do increase bleed risk
list some herbal products that interact with warfarin?
ginkgo, ginseng, st. johns wort
Are thrombolytics approved for tx of VTE?
no, but can use alteplase for PE
In patients with hypotension who do not have a high risk of bleeding, thrombolytic therapy is suggested
Prophylaxis of VTE is generally how long
10-14 days
Non-pharms for prophylaxis of VTE
graduated compression stockings and pneumatic compression devices decrease risk of VTE
T or F: LMWH are approved for both treatment and prevention of VTE
true
list some LMWH
- dalteparin
- enoxaparin
- nadroparin
- tinzaparin
UH is approved for prevention of VTE in which patients?
only for patients undergoing procedures with moderate risk
Who is fondaparinux approved for the prevention of VTE in?
approved for prevention of VTE in high-risk orthopedic patients
When can DOACs be used for prevention of VTE?
following elective total hip or knee replacement surgery
Can also use _____ for prevention of VTE
warfarin (vitamin K antagonist)
What is the Virchow triad?
- venous stasis
- damage/injury
- hypercoagulability
What is DOC in pregnancy?
LMWH (it induces less bone loss)
- UH used if LMWH not available
- can use fondaparinux if other agents can’t be used
*do not use DOACs or warfarin
Does LMWH or UH cross placenta?
neither of them cross placental barrier
How long do you treat in pregnancy?
min 3 months
What are we monitoring in pregnancy?
monitor anti-Xa levels to achieve a target of 0.5-1.0 U/mL 3-6 hours post dose
Why do we avoid warfarin in pregnancy?
teratogenic effects.
What can be used while breastfeeding?
warfarin, UH, LMWH may be used for 6 weeks after delivery for secondary prevention
What 2 drugs are approved for treatment of HIT (heparin-induced thrombocytopenia)
- argatroban
- danaparoid
