Venous ThromboEmbolism (VTE)
As long a hip and knee surgeries have been performed blood clots have occasionally occurred in the veins of the leg and pelvis. Very rarely a part of such a clot can break off and travel to the lung. This can reduce the oxygen carrying capacity. Deaths have been reported.
Cause of Blood Clots
There are several reasons for the development of blood clots following surgery. The body reacts to any wounding by activating the clotting cascade. Also, there is the release of disturbed bone marrow contents into the circulation when we drill into bone.
During surgery the leg must be manipulated temporarily kinking the veins and there is relative mobility. Some patients have a natural or inherited predisposition to developing blood clots. In patients with a personal or family history specific tests and recommendations are often necessary prior to considering a surgical procedure.
Reducing the Incidence of Blood Clots
Several measures are recommended to reduce the chance of blood clots.
Discontinuation of medications such as estrogens that increase to chance of blood clots
Thromboembolic stockings
Suctioning and irrigation of the bone during surgery
Mechanical compression devices
Regional anesthesia
Pumping your legs
Rapid mobilization after surgery
Blood thinning medications
Blood Thinning Medications
There are a number of blood thinning medications available. Aspirin and Coumadin (Warfarin) are the oldest and cheapest. Newer medications (Lovenox and Fragmin) are usually injected and often are more effective.
We don’t know for sure the optimal dose and duration of treatment for any given patient. Several recommendations have been offered. We are following one of the common recommendations and it seems to work well.