THE PLANTAR VENOUS PLEXUS AND APPLICATIONS OF A-V IMPULSE SYSTEM TECHNOLOGY

Introduction. The plantar venous plexus forcefully ejects blood from t he foot into the tibial veins as weight is placed on the heel and meta tarsal heads. Since post-revascularization edema appears to result in part from insufficient venous return relative to the sudden increase i n arterial inflow, we hypothesized that enhanced venous return by stim ulation of the plantar venous plexus' may reduce or eliminate this pos toperative problem. Also, low pressure arterial inflow might be enhanc ed by a reduction in distal venous pressure through activation of the plantar venous plexus. To test this hypotheses, a mechanical device (t he A-V Impulse System(R)) which stimulates the plantar venous plexus i n the nonambulatory patient was applied to patients with post-revascul arization edema and patients with end-stage distal ischemia. Methods. Patients undergoing distal vascular reconstruction for Limb salvage we re treated either with compression bandaging or the A-V Impulse System (R). Use of the foot pump on the operative leg began in the recovery r oom and continued for 7 days. Calf and ankle circumference were measur ed daily, beginning immediately preoperatively and continuing until po stoperative day 7. The preoperative calf and ankle circumference of th e operative leg were taken as baseline. Wound complications were also recorded. To determine whether augmentation of venous outflow can resu lt in enhanced arterial inflow in patients with severe peripheral arte rial occlusive disease, 7 extremities in. 5 patients with unreconstruc tible vascular disease have been treated. Ankle brachial indices range d from 0 - 0.31. The A-V Impulse System(R) was used for 4-6 hours each day with each pumping session lasting at least 2 hours. Feet were per iodically inspected for worsening of ulcers or new areas of skin injur y. Patients were evaluated daily for severity of rest pain, edema, ski n quality, and healing of ulcers.Results. There was a significant incr ease in venous velocities within both the common femoral and popliteal veins in both the control and treatment groups, despite the presence of significant lower extremity ischemia in the latter. Preliminary res ults in 10 patients demonstrated that, over the 7 day period of observ ation, controls demonstrated progressive increase in calf circumferenc e which was greatly reduced in patients who used the device. This incr ease in calf circumference occurred despite attempts at early limited ambulation in all patients in the postoperative period Controls also d emonstrated progressive ankle edema which was very prominent on postop erative day 1 and peaked on postoperative day 5. There was then a redu ction of ankle edema which may correlate to the onset of ambulation. T he A-V Impulse System(R) markedly reduced ankle edema during the first 5 postoperative days. All patients had at least a 1 cm reduction in c alf circumference and reported a significant reduction in rest pain wi thin 2 days of treatment. One patient demonstrated a return of her dor salis pedis pulse. Toe ulcers began to heal. There was no change in an kle-brachial indices. Cessation of treatment to less than 4 hours per day led to a recurrence of symptomatology, edema, and a worsening of u lcers. Conclusion. These preliminary data strongly suggest that the A- V Impulse System(R) may be of benefit in those patients after distal v ascular reconstruction as well as those with severe distal ischemia an d unreconstructible vascular disease.