Doctors use different clinical models to assess how likely it is that
deep vein thrombosis. They all take into consideration
your medical history, symptoms, other findings from the physical examination,
your major and minor risk factors, and whether there is another obvious
diagnosis. For example:
If you have one or more major risk factors (such
as previous deep vein thrombosis,
pulmonary embolism, or cancer) and certain symptoms of
deep vein thrombosis, and no other diagnosis seems obvious, you will probably
be considered high risk for deep vein
If you have a minor risk factor (such as pregnancy) or
minor symptoms, you will probably be considered lower risk for deep vein thrombosis.
If you have several minor
risk factors (pregnancy and smoking), or a combination of major and minor risk
factors, and symptoms, your risk may be medium or high risk.
Major risk factors for developing deep vein thrombosis include:
Prolonged (more than 3 days) bed
Abnormal blood clotting (hypercoagulable state), usually a
result of inherited genes from one or both parents. Protein S deficiency,
protein C deficiency, antithrombin III deficiency, and factor V Leiden are
Surgery, particularly major
hip or knee surgery, neurosurgery, and abdominal or chest surgery associated
Cancer and its treatment.
Paralysis due to
spinal cord injury.
Minor risk factors for developing deep vein thrombosis include:
After your doctor establishes your risk level for deep vein
thrombosis through the medical history and physical exam, an
ultrasound is usually done. Your ultrasound results
will help your doctor either diagnose deep vein thrombosis or decide how
aggressively to pursue further testing.