Fig 1.
Sites for recording the toe skin capillary flow and arterial pulse, and arterial inflow into toe and calf.
Numbers 1 and 2 depict arterial assist pump chambers.
Fig 2.
The big toe arterial pulse recording during arterial pump support.
First arrow at inflation time of chamber 1 (fore-foot), second of chamber 2 (mid-calf) and third deflation of both chambers. Note increase in pulse amplitude immediately after chambers inflation due to a 4–6 sec toe arterial dilatation, before chamber pressure reaches 120mmHg causing a 2 sec drop due to stop of arterial inflow.
Fig 3.
Laser Doppler recording of the big toe capillary flow velocity (in millivolts) during the designed arterial assist pump (arrows point 4–6 sec inflation of foot-calf chambers) in a patient with multifocal calf arteries occlusions.
The peak is followed by a short drop and then increase in flow returning to control values during the 16 sec (off) without compression.
Fig 4.
Laser Doppler recording of the big toe capillary flow velocity (in millivolts) part a) before (points 1–5), no assist (points 6–7), part b) during (points 8–9), no assist (point 10), part c) after (points 11–14), and no assist (point 15) Biocompression arterial pump application in a patient with multifocal calf arteries occlusions. In order to observe the pump effect on the capillary flow before and after IPC the venous occlusion plethysmographic method was used at venous occlusion pressures from 50 through 80, 100, 120 and 140 mmHg, before (points 1–5) and after (points 11–14) 20 arterial pump inflations. Horizontal lines at these points denote mean values. Oblique line in part b point 8 and 9 shows values during pump inflations. Note that capillary flow velocity remained increased after pump assist. Comparison of the pre- and post-IPC capillary flow velocity values showed their higher values after assist even at the plethysmographic arterial inflow occlusion as high as 140 mmHg.
Fig 5.
Laser Doppler recording of the big toe capillary flow velocity (in millivolts) before (upper part) and after (lower part) Biocompression arterial pump assist in a patient with multifocal calf arteries occlusions.
Control value (point 1). In order to observe the pump effect on the capillary flow before and after pump assist the venous occlusion plethysmographic method was used at venous occlusion pressures from 50 through 80, 100, 120 and 140 mmHg, before (points 2–5) and after (points 7–11) arterial pump inflations. Comparison of the pre- and post-IPC capillary flow velocity values showed higher values after support even at the plethysmographic arterial inflow occlusion of 140 mmHg.
Fig 6.
The circumference of the mid-toe and mid-calf was recorded during the arterial assist pump by strain gauge plethysmography in a patient with multifocal calf arteries changes.
Number 1 and 2 denote sequentially inflated chambers in front-foot and calf. Blue lines depict strain gauges position. Red lines show time point when inflations began and toe and calf circumferences changed. Elongation of the gauge was read off on the recorder graph scale in mm. Increase in circumference was brought about by the in-flowing blood. Inflation of chamber 1 brought about a 2 sec decrease in calf and increase in toe circumference. Inflation of chamber 2 caused increase of both calf and toe circumference. Deflation was followed by return to the pre-support values. Note that each chamber inflation was followed by increase in toe or calf circumference. This might have been the effect of filling up with blood in occluded toe and calf veins.
Fig 7.
Blood pressure in the great saphenous vein (GSV) at the ankle level during arterial support pump inflations.
Patient in a supine position. Increase of pressure during 10 inflations and fast decrease upon cessation of support. The pressure increase in the GSV proved stasis of venous blood. It may suggest also increase in venous capillaries.
Fig 8.
Venous occlusion plethysmography measuring arterial inflow at increasing occlusion pressures in a patient with multifocal changes in the calf arteries.
Calf occlusion chamber was inflated to 50 to 120 mmHg pressures before and after 20 compressions of the designed arterial assist pump. Simultaneous recordings in the calf and big toe. Curves show increase of circumferences at each applied 0 mmHg occlusion pressures. Before compression: calf–fast rise of curves reaching same level at occlusion pressures up to 120mmHg, big toe- decreasing peak of circumference at occlusion pressures 100 and 120 mmHg. After compression: calf- no evident difference with before arterial assist, big toe- peaks higher than before assist. The difference may be due to the increase in capillary flow.
Fig 9.
Laser Doppler recording of the big toe capillary flow velocity (in millivolts) in two patients with multifocal calf arteries occlusions after 2 years of the applied arterial assist.
a-before and b- after long-term support. pre- and post-IPC scales adjusted. Evidently higher amplitudes after long-term therapy.
Fig 10.
Laser Doppler recording of the big toe capillary flow velocity (in millivolts) in a patient with occlusion of the superficial femoral artery not suitable for reconstruction after 2 years of the applied arterial assist.
a-before and b- after long-term assist. Pre- and post-IPC recording scales adjusted. Although the amplitudes before therapy were high there was an evident increase following the long-term assist.
Fig 11.
Calf and big toe plethysmography before and after 2 years of daily use of our arterial assist pump in a patient with calf multifocal arterial occlusions.
The peak levels of calf arterial inflow do not show major difference before and after therapy. The peak levels of big toe inflow evidently higher than before therapy. Note no stop to arterial capillary flow at venous occlusion pressure of 150 mmHg.
Table 1.
Plethysmography of calf and big-toe volume changes before and after 2 years of daily arterial pneumatic support (in ml).