INTERMITTENT CALF AND FOOT COMPRESSION INCREASES LOWER-EXTREMITY BLOOD-FLOW

PURPOSE: Although foot compression increases foot skin perfusion and c alf compression increases popliteal artery blood flow, these compressi on techniques have not been evaluated in combination. The purpose of t his study was to evaluate whether calf and foot compression applied se parately and simultaneously increase popliteal artery blood flow and/o r foot skin perfusion, and to assess the relative merits of compressio n in patients with superficial femoral artery occlusion. METHODS: Twen ty-two legs from 12 normal volunteers with ankle/brachial indices (ABI s) >0.96, and 10 legs from 7 claudicator patients with angiographicall y documented superficial femoral artery (SFA) occlusion and patent pop liteal arteries with ABIs <0.8 were studied in the sitting positions. Calf and foot cuffs connected to a rapidly inflating and deflating tim ed-pressure pump (Art-Assist-AA 1000; ACI Medical Inc., San Marcos, Ca lifornia) were applied to the subject in the sitting position. Skin bl ood flow of the great toe was measured with a laser doppler (Laserflo model BPM 403A; TSP Inc., St, Paul, Minnesota), and popliteal artery b lood flow was measured using duplex ultrasonography (ATL-Ultramark 9; Advanced Tech Laboratory, Bothell, Washington), Foot and card compress ion was applied separately and simultaneously at 120 mm Hg pressure, w ith a 10-second inflation and 20-second deflation cycle. Popliteal art ery blood flow and foot skin perfusion were recorded and the mean of 6 cycles calculated. RESULTS: precompression popliteal artery blood blo w (mL/min) for volunteers was 38.86 +/- 3.94, and for patients was 86. 30 +/- 14.55 (P = 0.001), Precompression foot skier perfusion (mL/min/ 100/g tissue) for volunteers was 1.67 +/- 0.29, and for patients was 4.00 +/- 0.92 (P = 0.01). With the application of calf, foot, and simu ltaneous calf and foot compression, the popliteal artery blood flow in creased in volunteers by 124%, 54%, and 173%, respectively, and in pat ients by 76%, 13%, and 50%. Foot skin perfusion increased in volunteer s by 260%, 500%, and 328%, respectively, and in patients by 116%, 246% , and 188%. Relative increases in popliteal artery blood flow and foot skin perfusion were higher in volunteers compared with patients durin g compression; however, the absolute values for foot skin perfusion an d popliteal artery blood flow were consistently higher in patients. CO NCLUSIONS: Measured in the sitting position, the resting popliteal art ery blood flow and foot skin perfusion are greater in patients with SF A occlusion compared with normal volunteers. Following compression, po pliteal artery blood flow and foot skin perfusion increased in both gr oups, but relatively more in volunteers, Increases in popliteal artery blood flow are significantly higher with calf compression than with f oot compression for both groups. A patent SFA allows for additive incr eases in popliteal artery blood flow with simultaneous foot and calf c ompression in normal persons, whereas this is not observed in patients . However, the increases in foot skin perfusion in patients with an oc cluded SFA parallel the increases shown in normal volunteers, with sep arate and simultaneous foot and calf compression.