Risk Factors

In addition to a clear description of the presenting symptoms it is also necessary to ascertain if any risk factors for PE are present.

The British Thoracic Society 20037 splits these into major and minor risk factors. The presence of a major risk factor conveys a 5-20 times increased risk of a PE to the patient whilst a minor factor conveys a 2-3 times increased risk (Table 1).

Similarly, NICE guidelines suggest that risk factors for VTE include a prior history of DVT, age over 60 years, surgery, obesity, prolonged travel, acute medical illness, cancer, immobility, thrombophilia (an abnormal tendency for the blood to clot) and pregnancy.

Table 1: Risk factors for PE
Major risk factors (relative risk 5-20)
Surgery Major abdominal/pelvic surgery
Hip or knee replacement
Post operative intensive care
Obstetrics Late pregnancy
Caesarian section
Lower limb problems Fracture
Varicose veins
Malignancy Abdominal/pelvic
Reduced mobility Hospitalisation
Institutional care
Previous proven venous thromboembolism
Minor risk factors (relative risk 2-4)
Cardiovascular Congenital heart disease
Congestive cardiac failure
Superficial venous thrombosis
Indwelling central vein catheter
Oestrogens Oral contraceptive
Hormone replacement therapy
Miscellaneous COPD
Neurological disability
Occult malignancy
Thrombotic disorders
Long distance sedentary travel

A full list of risk factors can be viewed here.