An alert that pops up when doctors place orders on the hospital’s computer system may help prevent blood clots in high-risk patients, according to a report in The New England Journal of Medicine.

Limited movement, certain drugs, recent surgery, and diseases, such as cancer, are among the risk factors for blood clots in hospitalized patients. Such clots typically occur in the veins of the legs, a condition known as deep-vein thrombosis or DVT. However, sometimes these clots break off and travel to the lungs, a potentially fatal problem called Pulmonary embolism or PE.

In the present study, the computer alert system dramatically reduced the occurrence of both DVT and PE among hospitalized patients.

With the system, a warning that a particular patient is at high risk for clots appears on the computer screen when a doctor logs in to enter orders. To dismiss the warning, the physician must complete a few screens that provide the opportunity to order drugs or special stockings that reduce the risk of clots.

“We were just flabbergasted in a very joyous way about the results of this trial,” senior author Dr. Samuel Z. Goldhaber, from Brigham and Women’s Hospital in Boston, told Reuters Health.

Not only did the alert system drastically cut the risk of DVT and PE, there was no increase in bleeding problems, a concern when anti-clotting drugs are given.

“As far as I know, no other study looking at order alert systems has ever shown that you can reduce the rate of DVT and PE. Past studies have shown that you could increase the number of orders written (for preventative measures),” but they weren’t really designed to determine if the rates of clotting problems fell, Goldhaber explained.

The study involved 2506 hospitalized patients who were at high risk of clots and were randomly assigned to the alert group or to a comparison group, in which no special alert was issued.

Anti-clotting drugs and stockings were ordered more often in the alert group than in the comparison group. At 90-day follow-up, the rate of DVT or PE in the alert group was 4.9 percent, much lower than the 8.2 percent rate seen in the comparison group. This means that the alert system cut the risk of clotting problems by 41 percent.

As good as the results were, Goldhaber said there is still room for improvement. “Two thirds of the time, our alert was killed” without the doctor ordering any preventative measures, he said. “I think the next step will be to delve into this issue a little bit more.”

In a related editorial, Dr. Pierre Durieux, from Hopital Europeen Georges Pompidou in Paris, notes that “it is important to remember that clinical alerts are tools that help but do not transform the decision-making process. Ultimately, the physician, not the computer, makes the decision.”

SOURCE: The New England Journal of Medicine, March 10, 2005.