Mercy Hospital Department of Emergency Medicine
              DVT Evaluation Guidelines 11/16/99

Assess Clinical Probability of DVT (see Table Below)
 - Low/Intermediate Probability -> D-Dimer ELISA test
   + Positive (>500 ug/L) -> Doppler Ultrasound of Lower Extremities ->
     Positive: Treat; Negative: Discharge
   + Negative (<500 ug/L): Discharge
 - High Probability -> Doppler Ultrasound of Lower Extremities ->
   + Positive: treat;
     Negative:  repeat ultrasound in 1-2 days, or contrast venogram

Clinical Pre-Test Probability for DVT
Item                                            Score
-----------------------------------------------------
Active cancer (treatment ongoing or
 within previous 6 months)                      +1
Paralysis, paresis, or recent immobilization    +1
Recently bedridden for more than 3 days or
 major surgey within 4 weeks                    +1
Localized tenderness along distribution
 of deep venous system                          +1
Entire leg swollen                              +1
Calf swelling by more than 3 cm when compared
 with the asymptomatic leg (measure 10 cm
 below tibial tuberosity)                       +1
Pitting edema (greater in symptomatic leg)      +1
Collateral superficial veins (non-varicose)     +1
Alternative diagnosis as likely or greater
 than that of DVT                               -2

High: >=3  Intermediate 1-2   Low <=0