title: The influence of inflation rate on the hematologic and hemodynamic effects of intermittent pneumatic calf compression for deep vein thrombosis prophylaxis.
abstract: OBJECTIVE
  The study was conducted to determine whether the different inflation rates of intermittent pneumatic compression systems used in deep vein thrombosis prophylaxis influence their hematologic and hemodynamic effects.
  
  
  METHODS
  A rapidly inflating intermittent calf compression system and a more gently inflating equivalent were applied to 20 healthy male volunteers for 2 hours each. Venous blood samples were taken for analysis of blood coagulation and fibrinolytic potential. Blood flow velocity was measured in the femoral vein with Doppler ultrasound.
  
  
  RESULTS
  Tissue factor pathway inhibitor significantly increased after the 2 hours of compression for both pumps (78.0 to 85.0 ng/mL rapid, P = .004; 76.5 to 78.0 ng/mL gentle, P = .5), as did plasminogen activator activity (0.85 to 1.05 IU/mL rapid, P = .006; 0.85 to 1.5 IU/mL gentle, P = 0.5). Plasminogen activator inhibitor 1 activity was reduced, although only approaching significance for the gentle system (16.5 to 14.3 AU/mL, P = .06). A D-dimer test for global fibrinolysis showed significant increases for the gently inflating system (97 to 411 ng/mL P < .001) but not for the rapidly inflating system (276 to 350 ng/mL P = .9). The rapidly inflating system produced significantly higher venous peak velocities and augmentations as expected.
  
  
  CONCLUSIONS
  Although the data confirm that both types of intermittent compression suppress procoagulant activation, rapid inflation clearly produced no extra benefit in increasing global fibrinolysis, and may be less hematologically effective.
authors.affiliation: Department of Medical Physics and Bioengineering, Wales College of Medicine, Cardiff, United Kingdom. morrisrj@cf.ac.uk
authors.forename: Rhys J
authors.initials: RJ
authors.lastname: Morris
authors.forename: John C
authors.initials: JC
authors.lastname: Giddings
authors.forename: Heather M
authors.initials: HM
authors.lastname: Ralis
authors.forename: Gwyneth M
authors.initials: GM
authors.lastname: Jennings
authors.forename: Delyth A
authors.initials: DA
authors.lastname: Davies
authors.forename: John P
authors.initials: JP
authors.lastname: Woodcock
authors.forename: Frank D J
authors.initials: FD
authors.lastname: Dunstan
mesh_terms: D000328:Adult; D001777:Blood Coagulation / Q000502:physiology*; D001783:Blood Flow Velocity; D005268:Femoral Vein / Q000000981:diagnostic imaging / Q000503:physiopathology; D005500:Follow-Up Studies; D006801:Humans; D048228:Intermittent Pneumatic Compression Devices; D008297:Male; D012016:Reference Values; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler; D020246:Venous Thrombosis / Q000097:blood / Q000503:physiopathology / Q000517:prevention & control*