P1: RLJ/OZN P2: KUF
0521779407-D-01 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:41
Deep Venous Thrombosis 465specific therapy
Indications
■Any DVT in the popliteal vein or above
■Calf DVT
➣treat with anticoagulation if symptomatic
➣If asymptomatic, anticoagulate, or
➣Observe and document no progression to popliteal v. with serial
duplex
➣Only 20% will propagate to higher level
■Unfractionated or low-molecule weight (LMW) heparin
➣If using unfractionated heparin, must achieve therapeutic levels
within 24 hours
➣Convert to coumadin within 2–3 days
➣LMW heparin allows outpatient treatment, no need to check PTT
➣Contraindications
Prior heparin allergy
Documented prior heparin-induced thrombocyotpenia
Ongoing bleeding from another site
Recent neurological surgery
➣Side effects
Heparin-induced thrombocytopenia (HIT)
Develops in 1–3% of patients
Can occur with both unfractionated and
Has mild (type I) and severe (type II) forms
Mild is asymptomatic drop in platelet count
Severe is pro-thrombotic with arterial and venous throm-
boses
Discontinue heparin; check anti-platelet Ab titer
Switch to either heparinoid or thrombin inhibitor and then
coumadin
➣Bleeding
Much lower incidence with LMW heparin
Treat with: blood replacement if needed and reversal of heparin
(fresh frozen plasma)
■Coumadin (warfarin sodium)
➣Dose to keep INR between 2 and 3
➣Continue for 6 months
➣If recurrent, may need lifelong treatment
■Contraindications
➣Pregnancy – use LMW heparin (can breastfeed also on heparin)
➣Coumadin allergy