Haemodynamic effect of intermittent pneumatic compression of the leg after infrainguinal arterial bypass grafting

Background: Intermittent pneumatic compression (IPC) may increase blood flow through infrainguinal arterial grafts, and has potential clinical application as blood flow velocity attenuation often precedes graft failure. The present study examined the immediate effects of IPC applied to the foot (IPCfoot), the calf (IPCcalf) and to both simultaneously (IPCfoot+calf) on the haemodynamics of infrainguinal bypass grafts. Methods: Eighteen femoropopliteal and 18 femorodistal autologous vein grafts were studied; all had a resting ankle: brachial pressure index of 0.9 or more. Clinical examination, graft surveillance and measurement of graft haemodynamics were conducted at rest and within 5 s of IPC in each mode using duplex imaging. Outcome measures included peak systolic (PSV), mean (MV) and end diastolic (EDV) velocities, pulsatility index (PI) and volume flow in the graft. Results: All IPC modes significantly enhanced MV, PSV, EDV and volume flow in both graft types; IPCfoot+calf was the most effective. IPCfoot+calf enhanced median volume flow, MV and PSV in femoropopliteal grafts by 182, 236 and 49 percent, respectively, and attenuated PI by 61 percent. Enhancement in femorodistal grafts was 273, 179 and 53 per cent respectively, and PI attenuation was 63 per cent. Conclusion: IPC was effective in improving infrainguinal graft flow velocity, probably by reducing peripheral resistance. IPC has the potential to reduce the risk of bypass graft thrombosis.