Surgeon general urges more vigilance on dangerous clots

Washington -- Deep vein thrombosis and pulmonary embolism affect 350,000 to 600,000 Americans each year, but often they are unrecognized at the earliest and most treatable stages.

With an eye toward elevating awareness of these potentially serious medical conditions, acting Surgeon General Steven K. Galson, MD, MPH, issued a "Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism." He introduced the publication Sept. 15 at the second annual meeting of the Venous Disease Coalition in Washington, D.C.

"DVT and PE are often referred to as 'silent' conditions -- they can occur suddenly and without symptoms. In nearly half of the cases, there are no apparent symptoms," he said. Although gains have been made in understanding how these dangerous clots develop and how to prevent, diagnose and treat them, that knowledge is not always applied systematically, he added.

The conditions generally keep a low profile, but they hit the headlines when they strike young, seemingly healthy individuals. NBC journalist David Bloom died in 2003 at age 39 of DVT and PE while covering the Iraq war, where he spent hours crouched in the close confines of a tank. His widow, Melanie, who attended the surgeon general's meeting, has since worked to spread the word about the dangers of DVT.

The two conditions may contribute to as many as 100,000 deaths each year, Dr. Galson said. That number is expected to rise as the population ages because patients older than 50 are at increased risk.

"It is clear that we are dealing with a major health problem," noted Elizabeth Nabel, MD, director of the National Heart Lung and Blood Institute, who spoke at the event.

The call also is intended to spell out certain warning signs to the primary care physician, who is often the first to detect a clot, Dr. Nabel said. Initial symptoms can be subtle.

Mistaken identity

Patients may have swelling or pain in an arm or leg, skin redness or a warm spot on a leg. Physicians first might consider diagnoses of skin infections or muscle strains instead of DVT. In the case of shortness of breath caused by a pulmonary embolism, the patient may be thought simply to be out of shape, Dr. Nabel said.

Le Keisha Ruffin, 32, described several fruitless trips to emergency departments when pain in her side and chest from an undiagnosed PE became so sharp "it felt like someone was literally stabbing me over and over again in the same spot." She was told the pain was from the birth of her daughter by cesarean section.

The proper diagnosis was made weeks later after a hot bath at home resulted in massive swelling in her right leg and she was rushed back to the emergency department. A physician told Ruffin that the DVT in her leg had caused one of the largest blood clots the physician had ever seen. Plus, part of the clot had broken off and caused a PE. She was told she might not have lived through the night had she not received help.

To prevent such occurrences and speed recognition of these conditions, the Agency for Healthcare Research and Quality published a 12-page patient guide and a 60-page physician guide on preventing and treating dangerous blood clots, said AHRQ Director Carolyn Clancy, MD. "We know how to prevent many of these dangerous blood clots, and these guides will help patients and clinicians put that knowledge to work to improve care."

The clinician guide, "Preventing Hospital-Acquired Venous Thromboembolism: A Guide for Effective Quality Improvement," is intended to help hospitals and clinicians implement successful processes to prevent dangerous blood clots, Dr. Clancy said. It identifies such clots as the "most common, preventable cause of hospital deaths."

The document also points to additional triggers for DVT that include taking hormones, having a bad bump or bruise, having had a stroke, being obese, or taking a trip of more than an hour in a car, airplane, bus or train. Certain inherited blood disorders also can make clots more likely.

NHLBI also is funding new research on the two conditions. Studies are under way on treatment for damaged veins and valves following DVT and on improving the health and well-being of elderly patients at risk for dangerous blood clots.

The institute also is launching the first multicenter, randomized clinical trial of genotype-guided dosing of warfarin, the most common blood-thinning treatment for those with diagnosed clots. The study will examine whether the use of clinical plus genetic data during warfarin initiation can lead to better and safer treatment.

Meanwhile, the AMA and other groups have developed the brochure "Personalized health care report 2008: Warfarin and genetic testing." It is designed for physicians and other health care providers who commonly prescribe warfarin but who may not have had exposure to pharmacogenomics and genetic testing. It outlines the effects of variations in the genes CYP2C9 and VKORC1 on warfarin metabolism and response, and summarizes the genetic testing available to determine whether a patient carries such gene variations.