Deep Vein Thrombosis Prophylaxis after Abdominal Surgery - what is the role of deep venous?

One of the most common causes of death in the hospitalized patient is pulmonary embolism (PE) caused by a deep vein thrombosis.
While many of these individuals may have had a terminal illness leading to embolism, a significant number of deaths occur in patients who had comparatively minor ailments and who might otherwise have lived normal and healthy lives.
It is estimated that one in 100 patients admitted to a hospital dies because of PE. It appears possible than more than one-half of these at-risk patients could be saved if effective prophylaxis was used. For example, patients undergoing major operations without receiving prophylaxis are put at risk of fatal PE and stand an even greater risk of morbidity from related conditions.

See http://www.outcomes-umassmed.org/dvt/best_practice/ f
http://www.drugs.com/enc/pulmonary-embolus.html