The prevention of deep vein thrombosis, with particular reference to mechanical methods of prevention.

Mechanical methods of preventing deep vein thrombosis have been surveyed. The best means of preventing venous stasis has been shown to be by intermittent compression of the legs. Use of intermittent compression will prevent isotopically detectable deep venous thrombosis in 82 percent of patients and in malignancy in 90 percent of patients. The only other prophylactic measure of comparable effectiveness is administration of low-dose subcutaneous heparin. Intermittent compression need only be applied during the operation and is cheap, foolproof, and safe. Intermittent compression acts by squeezing empty the soleal sinuses and large valve pockets in the major veins in which thrombi form while venous flow is slowed during operation. A combination of intermittent compression and administration of low-dose subcutaneous heparin has been found to be no more effective than is intermittent compression alone.