Doctors may in future be able to prevent many cases of deep-vein thrombosis

Mar 9 2005

Deep-vein thrombosis (DVT), a disease of the circulation that causes potentially fatal blood clots. It occurs most often in people who have not been able to exercise normally. Doctors may in future be able to prevent many cases of deep-vein thrombosis, commonly referred to as DVT, a disease of the circulation that causes potentially fatal blood clots. It occurs most often in people who have not been able to exercise normally.

Developing DVT after long plane rides is often called "economy-class syndrome" or "coach-class syndrome," because seating and leg room are particularly cramped for passengers in economy class. However, first-class and business-class passengers also get DVT, so this problem isn't solely due to sitting still in tight quarters for many hours.

In a study published in this week's edition of The New England Journal of Medicine an experimental computer alert system was tested at Brigham and Women's Hospital in Boston. The computer program, linked to the hospital's patient database, identified more than 2,500 patients at risk of developing DVT and who may have needed preventive care, such as anti-coagulant drugs.

The program randomly sorted half of the patients into an intervention group in which doctors were warned of their risk for developing DVT, and the remaining patients to a control group in which no alert was issued.

Study co-author Samuel Goldhaber and his colleagues discovered that more than twice as many people were treated as a result of the automated alerts, producing a 41 percent decrease in the risk of either a deep-vein thrombosis or a lung embolism, which is caused when a clot lodges in the lung. As many as 2 million Americans develop the clots each year, usually because of inactivity, cancer or dehydration.

The clots often develop in hospital patients who can not move around, doctors often do not take essential steps to prevent them.

Such clots are "by-and-large preventable," and the study results may encourage hospitals to take similar steps to identify and treat at-risk patients.

A statement released said the alert system had the potential to save thousands of lives, but they could not as yet provide conclusive proof as the study group was to small to detect a significant reduction in the death rate.Such clots are preventable and life quality is capable of being improved by the use of information the tests deliver.

In an editorial in the Journal, Pierre Durieux of the George Pompidou European Hospital in Paris said the test illustrates the benefits of automated alerts for doctors.

Deep venous thrombosis affects mainly the veins in the lower leg and the thigh. It involves the formation of a clot (thrombus) in the larger veins of the area. This thrombus may interfere with circulation of the area, and it may break off and travel through the blood stream (embolize). The embolus thus created can lodge in the brain, lungs, heart, or other area, causing severe damage to that organ.

Risks include prolonged sitting, bedrest or immobilization (such as on long plane or car trips), recent surgery or trauma (especially hip, knee or gynecological surgery), fractures, childbirth within the last 6 months and the use of medications such as estrogen and birth control pills. Risks also include a history of polycythemia vera, malignant tumor, and inherited or acquired hypercoagulability (changes in the levels of blood clotting factors making the blood more likely to clot).

Deep venous thrombosis is more commonly seen in adults over age 60 but can occur in any age group.