The influence of inflation rate on the hematologic and hemodynamic effects of intermittent pneumatic calf compression for deep vein thrombosis prophylaxis.


Morris RJ, Giddings JC, Ralis HM, Jennings GM, Davies DA, Woodcock JP, Dunstan FD.


J Vasc Surg. 2006 Nov;44(5):1039-45. Epub 2006 Sep 6.

OBJECTIVE: The study was conducted to determine whether the different inflation rates of intermittent pneumatic compression systems used in deep vein thrombosis prophylaxis influence their hematologic and hemodynamic effects. METHODS: A rapidly inflating intermittent calf compression system and a more gently inflating equivalent were applied to 20 healthy male volunteers for 2 hours each. Venous blood samples were taken for analysis of blood coagulation and fibrinolytic potential. Blood flow velocity was measured in the femoral vein with Doppler ultrasound. RESULTS: Tissue factor pathway inhibitor significantly increased after the 2 hours of compression for both pumps (78.0 to 85.0 ng/mL rapid, P = .004; 76.5 to 78.0 ng/mL gentle, P = .5), as did plasminogen activator activity (0.85 to 1.05 IU/mL rapid, P = .006; 0.85 to 1.5 IU/mL gentle, P = 0.5). Plasminogen activator inhibitor 1 activity was reduced, although only approaching significance for the gentle system (16.5 to 14.3 AU/mL, P = .06). A D-dimer test for global fibrinolysis showed significant increases for the gently inflating system (97 to 411 ng/mL P < .001) but not for the rapidly inflating system (276 to 350 ng/mL P = .9). The rapidly inflating system produced significantly higher venous peak velocities and augmentations as expected. CONCLUSIONS: Although the data confirm that both types of intermittent compression suppress procoagulant activation, rapid inflation clearly produced no extra benefit in increasing global fibrinolysis, and may be less hematologically effective.