title: Enhancing venous outflow in the lower limb with intermittent pneumatic compression. A comparative haemodynamic analysis on the effect of foot vs. calf vs. foot and calf compression.
abstract: OBJECTIVE
  intermittent pneumatic compression (IPC), an established method of deep-vein thrombosis prophylaxis, is also an effective means of leg inflow enhancement, improving the walking capacity and ankle pressure of claudicants, long-term. This study, using duplex ultrasonography, compares the haemodynamic effect of IPC of the (a) foot (at 120 mmHg [IPC(foot/120 mmHg)], and 180 mmHg [IPC(foot/180 mmHg)]), (b) calf (IPC(calf), 120 mmHg) and (c) both simultaneously (IPC(foot+calf), 120 mmHg), on the venous outflow of 20 legs of normals and 25 legs of claudicants.
  
  
  RESULTS
  the peak and mean velocities, volume flow and pulsatility index in the superficial femoral and popliteal veins of both groups increased significantly with all IPC modes (p<0.001). IPC(foot+calf)produced the highest enhancement followed by IPC(calf)(p<0.01), which was more effective (p<0.001) than either IPC(foot/180 mmHg)or IPC(foot/120 mmHg). The venous volume expelled with IPC(calf)and IPC(foot+calf)was 2-2.5 and 3-3.5 times that with IPC(foot/180 mmHg)respectively. Velocity enhancement with IPC was similar between groups and the superficial femoral and popliteal veins. IPC(foot/180 mmHg)produced higher (p<0. 01) flow velocities than IPC(foot/120 mmHg)in both groups and veins examined; however, differences were limited.
  
  
  CONCLUSIONS
  all IPC modes proved effective, IPC(foot+calf)generating the highest venous outflow enhancement. Higher venous volumes expelled with IPC(foot+calf)explain its reported superiority on leg inflow over the other modes. Increase of applied pressure from 120 to 180 mmHg with IPC(foot)offered only a small outflow improvement. Venous haemodynamics at rest and with IPC in claudicants do not differ significantly from those in healthy subjects.
authors.affiliation: Irvine Laboratory for Cardiovascular Investigation and Research, Academic Vascular Unit, London, Paddington, UK.
authors.forename: K T
authors.initials: KT
authors.lastname: Delis
authors.forename: G
authors.initials: G
authors.lastname: Slimani
authors.forename: H M
authors.initials: HM
authors.lastname: Hafez
authors.forename: A N
authors.initials: AN
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D001810:Blood Volume / Q000502:physiology; D005260:Female; D005268:Femoral Vein / Q000000981:diagnostic imaging / Q000502:physiology*; D005528:Foot / Q000098:blood supply* / Q000000981:diagnostic imaging; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007383:Intermittent Claudication / Q000000981:diagnostic imaging / Q000628:therapy*; D007866:Leg / Q000098:blood supply* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011152:Popliteal Vein / Q000000981:diagnostic imaging / Q000502:physiology*; D011312:Pressure; D011673:Pulsatile Flow / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D013223:Statistics as Topic; D018615:Ultrasonography, Doppler, Color; D018616:Ultrasonography, Doppler, Duplex; D020246:Venous Thrombosis / Q000517:prevention & control; D016138:Walking / Q000502:physiology