Background and Goal of Study: There was no simple and easy method for comparing anti-DVT (deep vein thrombosis) foot pumps performance. An Ultrasonic Doppler flow meter needs much time and effort for multi time measurements. We made a simple and easy comparing method using bioimpedance measurement.
Materials and Methods: We studied six types foot pumps in each 15 male health volunteers aged 32.1 ± 8.7 (mean ± SD). After electrodes fixation on dorsal foot and frontal thigh, we measured bio-impedance with computer controlled LCR meter under 20 kHz 20 mA transmit current. Compression pressure was monitored with ventilator performance analyzer. Studied foot pumps are A-V Impulse System old/new type (Novamedix), Venostream (Terumo), DVT-2500 (Medomer), Venaflow (Aircast), Wizair DVT (MCS).
Results and Discussions: Control leg impedance was 849.2 ± 94.2. Impedance changes are clear (Figure 1) and parallel with compression pressure waves. Impedance changes in Venostream, A-V Impulse old type, DVT-2500 were significantly higher than Wizair DVT and A-V Impulse new type. Bioimpedance changes response to both intra cellular fluid and extra cellular fluid. But changes in the short period were supposed to show blood volume changes (1,2). Therefore impedance change is a good blood volume shift parameter.
Conclusion(s): Bio-impedance measurement is simple and easy method to compare the foot pump's performance.
1 Watanabe H, et al. 12th WCA Montreal 2000; P7.2.39.
2 Watanabe H, et al. 15th CENSA Florence 2001; P17.