OHSU Outpatient Anticoagulation Guidelines
Outpatient Disease Management of Deep Venous Thrombosis
*Eligible population includes patients with diagnosis of DVT without contraindications to outpatient management. Relative contraindications include:
respiratory instability, extensive clot burden, known potential for non-compliance, recent surgery/trauma, active bleeding, severe HTN, pregnancy, HIT,
thrombocytopenia < 80,000
* Individual patient considerations and advances in medical science may supersede or modify these recommendations.
Key Components
Recommendations
Diagnosis of acute DVT

Risk/benefit assessment



OAT selection





Associated interventions


Intensity of OAT

Perform initial comprehensive history and physical
considering conditions predisposing to DVT
DVT confirmed by duplex ultrasonography or venography
Assess risk for clotting (identify any provoking factors
which will continue)
Assess risk for bleeding (HAS-BLED, HEMORRHAGES,
Outpatient Bleeding Risk Index)
Start LMW or fondaparinaux
Initiate concurrent warfarin therapy at 5 mg orally on day
of DVT diagnosis; titrate to INR range of 2.0 – 3.0.
Continue LMW (minimum of 5 days) until INR range 2.0 –
3.0 for ≥ 24 hours
Consider rivaroxaban if LMW contraindicated or cost is
prohibitive when FDA approved
Consider dabigatran instead of warfarin if: age < 75, no
renal disease, no history of GI bleeding and patient is
taking full PO, and has no renal impairment (Cr Cl < 50
ml/min), cost is not an issue
Compression socks 30 – 40 mmHG at ankle for 2 years
Pain management: acetaminophen, narcotic if pain
severe. Avoid NSAIDS if possible (if needed use salsalate
or COX-II inhibitor).
Target INR (range) 2.5 (2.0 – 3.0)
Comments
Initial or baseline lab work
Testing/monitoring
Duration of
therapy/reevaluation


Obtain baseline PT/INR, aPTT, CBC with plts
Creatinine for elderly patients (>75yrs), those with Hx
CHF or renal disease
 LFTs if Hx liver disease
 Hypercoagulability work up if unprovoked and patient is
young, unusual site, or there is
 First INR day 3 after warfarin initiation
 Daily INRs thereafter while on LMW or fondaparinaux
 After sub Q medication discontinued INR testing every 2 –
3 times per week for the next 1 – 2 wks, weekly testing
until stable, then every 4 weeks
 For indefinite therapy may check every 12 weeks if
patient has stable INRs for 6 months or greater
Superficial venous thrombosis:
 NSAID/heat till resolution of signs and symptoms
 at least of 10-12 day course of prophylactic LMWH or
fondaparinux for patients with extensive (> 5cm), greater
saphenous, or painful SVT
Upper extremity DVT:
 Catheter related (esp PICC): remove catheter and hold
anticoagulation unless very symptomatic (risk of bleeding
with therapy can be as high as 25%)
 Spontaneous: 3 month of therapy.
Muscular calf vein (soleus or gastrocnemius) Thrombosis: 10
days of LMWH.
Calf Vein Thrombosis (tibial/peroneal): 6 weeks of therapy.
Proximal vein thrombosis (popliteal vein and above): 3 months
to indefinite. Duration of therapy influenced by number of
thrombosis, provoking factors (surgery, pregnancy, etc.) and
presence of hypercoagulable states
Provoked first DVT: 3 months.
• Provoking factors: trauma, surgery, bedrest > 72 hours,
pregnancy, estrogen, very long (> 10 hours) plane flights.
Idiopathic first DVT: At least 3 months then strongly consider
indefinite therapy. High risk (10-25%) of recurrence in next 2
years without anticoagulation.
• Risk groups for recurrence: Men, age > 65, postphlebitic syndrome, obesity, pulmonary
embolism as event
• Lesser risk of recurrence: women (esp. < 65)
• Role of post-therapy D-dimer – controversial – strong
risk factor for recurrence is positive (~9-10%/yr) but still 2.93.9%/yr risk with negative d-dimer
Referral
Two or more lower extremity proximal DVT: Indefinite
anticoagulation
 Vascular surgery for catheter directed thrombolytic
therapy for: 1) extensive UE thrombosis (especially if in a
dominant arm or a young patient) or 2) very symptomatic
common femoral or iliac thrombosis.
 Interventional Radiology for IVC filter removal (done with
therapeutic INR)
 Hematology for hypercoagluable work up in patients with
unusual DVT sites, idiopathic DVT
 Physical therapy for symptom relief
 Social worker/community services
 Interpreter services for language needs


Patient education/Health
literacy
Management Model
Specialty Populations
Dietician for complicated dietary needs
Primary Care Provider for health maintenance and nonanticoagulation related medical problems
 Teaching regarding: function of Anticoagulation Clinic,
purpose of anticoagulation medications, importance of
taking prescribed dosage, importance of regular blood
testing, reporting of medication changes, reporting of change
in tablet color, factors influencing anticoagulation (diet,
ETOH, activity, health, OTCs, herbal remedies), notification of
all providers/dentists, medications to avoid (ASA, NSAIDs,
OTCs, herbal remedies, acetaminophen precautions),
reporting signs of bleeding, contacting Anticoag Clinic staff,
pregnancy risks and contraception needs.
 Health Literacy: baseline understanding (accurately able to
explain reason for visit and relevant medical history, describe
the alteration in self-care routines/abilities resulting from
treatment, providers name and contact information,
anticoagulation medication dosage and reason for taking
anticoagulation medication, and verbalization of ability to
adhere to proposed treatment plan for medication, blood
testing, diet and activity), learning needs (disease/symptoms,
medication administration, pain management, diet, drugfood interactions, diagnostic tests, safety and infection
control) and barriers to learning (cognitive, physical,
pain/comfort level, hearing/visual/speech limitation, cultural,
emotional/fear, psychosocial, lack of desire/motivation,
reading inability, financial, religious and language)
Dedicated anticoagulation service
Patient Self Testing if meets criteria
Pregnancy: LMWH has been established to be both effective
and safer in pregnancy than standard heparin. Dose for body
weight and check levels after third dose then every month. Can
use LMWH or warfarin with breast feeding. Duration – entire
course of pregnancy and at least 6 weeks after delivery – total
should be at least three months.
Thrombophilia
• Inherited hypercoagulable states – raises risk of first
DVT but not a predictor of recurrence
• Severe acquired states – antiphospholipid antibody
syndrome, myeloproliferative disease, PNH, cancer –
consider long term anticoagulation
Cancer: Use of LMWH long term should be considered especially
if lung cancer or pancreatic cancer. Long term LMWH is
mandatory for warfarin failures. Incidentally discovered PE in
cancer patients have the same adverse outcome as symptomatic
PE and require aggressive antithrombotic therapy.
General Reference:
ACCP Conference on Antithrombotic and Thrombolytic Therapy. American College of Chest Physicians, 2012 (www.chestnet.org).