Pitto RP, Hamer H, Kuhle JW, Radspiel-Troger M, Pietsch M.
[Hemodynamics of the lower extremity with pneumatic foot compression. Effect on
leg position]
[Article in German]
Biomed Tech (Berl) 2001 May;46(5):124-8

Orthopadische Klinik mit Poliklinik Friedrich-Alexander-Universitat
Erlangen-Nurnberg Waldkrankenhaus, Rathsbergerstrasse 57 D-91054, Erlangen,
Deutschland. pitto@ortho.med.uni-erlangen.de

External pneumatic compression of the foot is being used more and more to
increase the venous blood flow in the lower limbs and thus reduce the risk of
postoperative deep venous thrombosis. We have investigated the efficacy of the
foot pump pneumatic compression device (A-V Impulse, Novamedix, Andover, England)
in 10 healthy subjects and in 10 patients undergoing total hip arthroplasty. The
velocity of venous blood flow in the common femoral artery was measured in the
horizontal, Trendelenburg (head-down, foot-up) and reverse Trendelenburg (head-up
and foot-down) positions using a duplex ultrasound unit (Sonoline Elegra,
Siemens, Erlangen, Germany) with a 5 MHz linear array probe. Application of the
foot pump produced an increase in venous blood flow velocity in all healthy
subjects and in all patients. In healthy subjects the mean increase in the
horizontal position was 31.18% (SD = 15.86%), and in the Trendelenburg position
20.72 (SD = 15.69%) (right limb). In the reverse Trendelenburg position, the foot
pump produced a mean increase of 94.08% (SD = 55.00%). The difference is
statistically significant (p < 0.005). In patients with a total hip arthroplasty,
the mean increase in the horizontal position was 28.67% (SD = 9.95%), and in the
Trendelenburg position 20.34% (SD = 17.85%) (operated limb). In the reverse
Trendelenburg, the foot pump produced a mean increase of 91.55% (SD = 42.38%).
The difference is statistically significant (p < 0.005). There was no noteworthy
difference in results between the controls and patients. Pneumatic compression
devices designed to reduce venous stasis are effective in decreasing the rate of
deep venous thrombosis after surgery on the lower limb. The results of the
present study show that the efficiency of the foot pump in increasing venous
return is improved by adopting the reverse Trendelenburg position. This may
increase its thromboprophylactic effect.