The haemodynamic and antithrombotic effects of intermittent pneumatic calf compression of femoral vein blood flow. A comparison between different pump types.

The haemodynamic effects of intermittent pneumatic calf compression on femoral vein blood flow in dogs and patients were studied by measurement with an electromagnetic flow meter. Two pump types were compared at different inflation pressures, one with a continuous inflation-deflation cycle of 2 min and the other causing inflation over 3 sec and deflation over 20 sec, with a frequency of three per minute. A fast rate of splint inflation created a greater haemodynamic change in net volume flow, peak flow and flow amplitude with an optimal pressure of 40 mmHg. The slower pump in fact decreased mean volume flow. Using an experimental thrombosis model both pump types significantly prolonged the occlusion time of implanted steel tubes, but did not differ from each other.