Tuesday, May 25, 2010
There are risks and then there are risks. Driving NASCAR fast comes with the risk of cars bumping, spinning out and flipping over. Add the risk of bleeding because your blood is thinned and it’s time to sit with the pit crew. Such is the story of Brian Vickers, a NASCAR driver on the sidelines because of pulmonary emboli or blood clots to the lung. When he gets to race again depends upon many things including why the blood clots happened in the first place.
Mr. Vickers is 26 years old and developed sharp chest pain when he took a breath; pleuritic chest pain in medical terms. Associated with a recently swollen leg, the diagnosis was probably made clinically by his physician. The leg swelled because of a blood clot or deep vein thrombosis. That clot broke off (now called an embolus) and traveled to the lung where it caused that part of the lung to stop working. Small blood clots present with shortness of breath and chest pain. Large clots can cause lung failure and death.
There are plenty of reasons to develop a deep vein thrombosis (DVT). Blood returns from the legs because muscles contract and milk blood back to the heart. Inactivity can cause blood to pool in the legs and clot while moving and walking circulates blood. Patients who are bedridden because of illness or injury are at risk and nursing care in the hospital deals with blood clot prevention. This includes patients with leg injuries who can’t walk. Often these patients are treated prophylactically with low dose blood thinners to prevent clot formation. Some patients have inborn errors of the clotting mechanism that cause blood to clot abnormally and form DVTs jus t because.
DVTs are inconvenient because they cause leg swelling and pain but it is a local problem. It’s only when that clot breaks off and travels that deadly occurs. The traveling clot (or embolus) travels in the veins that return blood to the right side of the heart and then gets pumped into the pulmonary arteries into the lung. The clot gets lodged in a segment of the artery. Just like any other area of the body that loses its blood supply, that part of the lung stops working causing shortness of breath and starts hurting. The large the clot load that damages the lung, the more lung function is lost and the sicker the patient can present.
The treatment for most blood clots is anti-coagulation or thinning the blood. This prevents further clot formation and decreases the risk that the clot that is already present will break off and embolize. But treatment isn’t good enough; the reason that the clot formed needs to be found to prevent further episodes and potentially prevent a life threatening disaster. Depending upon the situation, patients with DVTs have their blood thinned for three month and those with pulmonary emboli get treated for six months. If there is a genetic reason for the blood clot to form, treatment may be life long.
Every patient is different and treatment plans balance the risk of anti-coagulation with the risk of bleeding. These may include the risk falling or the interaction with other medications (antibiotics are a prime culprit). For a NASCAR driver who is always one turn away from a major wreck, the risk of bleeding is high and it is that reason why Mr. Vickers is on the sideline. His ability to return to competition depends upon why the clot happened. Was it because he sits is a car for hours on end driving in circles or is it because he has an inborn error of blood clotting? If it’s a blood clotting error, Mr. Vickers may need to take blood thinners forever and be unable to drive competitively again. Here’s hoping the clot happened because he was just sitting around too much.