Measurement of femoral vein blood flow during total hip replacement. Duplex ultrasound imaging with and without the use of a foot pump.

We examined ten femoral veins with duplex ultrasound during total hip replacement to demonstrate the operative manoeuvres which cause venous obstruction and to assess prophylactic measures which may overcome it. Exposure of the acetabulum by distraction of the femur with a hook was less likely to occlude flow than retraction with bone levers. Adequate exposure of the femoral shaft by adduction, flexion and either internal or external rotation caused cessation of flow in all cases. In four cases an A-V Impulse System foot pump was activated during periods of stasis. In each case it overcame the obstruction and produced peak velocities which were twice that of the resting state. In five cases, towards the end of the procedure, debris was seen travelling proximally through the femoral vein.