INTERMITTENT PNEUMATIC COMPRESSION AND FIBRINOLYSIS - DESCRIPTION OF A NEW MODEL

Objective. To develop a model which can be used to elucidate the time course and magnitude of changes in the fibrinolytic system associated with application of intermittent pneumatic compression (IPC). Experime ntal design. Intervention and response investigation with each subject serving as his own control. Setting. Clinical research laboratory in a large urban medical center. Patients. Healthy, non-smoking, male vol unteers between 20 and 40 years of age. Intervention. Femoral venous c atheter insertion. Blood samples were obtained via the catheter at fre quent intervals for six hours to determine the effect of catheter inse rtion on fibrinolytic parameters. Measures. Tissue plasminogen activat or (tPA), plasminogen activator inhibitor type 1 (PAI-1), t-PA/PAI-1 c omplex (t-PA/PAI-1) and euglobulin lysis time (ELT). Results. Placemen t of femoral venous catheters led to early elevations in t-PA and PAI- 1, which returned to baseline within four hours of catheter insertion. The complex, t-PA/PAI-1, revealed a biphasic response with elevations at the beginning and end of the six-hour study period. Euglobulin lys is time was unchanged. No catheter-related complications occurred in t he study. Conclusions. We have developed a model which allows frequent assessment of the components of the fibrinolytic system. Although cat heter placement induces significant elevations of t-PA, PAI-1, and t-P A/PAI-1, a new fibrinolytic baseline was established within four hours of catheter placement. The new baseline will provide for subsequent d etection of any changes in systemic fibrinolysis which result from IPC .