Determination of the global fibrinolytic state
Fibrinolysis consists of a plasmatic part and a cellular part. A rapid global assay for plasmatic fibrinolysis is the fibrinolysis parameters assay (FIPA). Cellular fibrinolysis is measured by testing the clot lysis capacity using the microtitre plate clot lysis assay with polymorphonuclear neutrophils (CLA-PMN). Individual citrated plasma or pooled normal plasma (50 μl) of 232 patients was recalcified, incubated for 90 min at 37°C, oxidized with 0 or 1.5 mmol/l (final concentration) chloramine-T, and supplemented with 50 μl respective polymorphonuclear neutrophil plasma. The turbidity of the clots was measured at 405 nm after 12 h and 60 h (37°C). Plasma (50 μl) was also incubated with 5 μl of 100 IU/ml urokinase, 6 mmol/l tranexamic acid, 6% human albumin for 10 min (37°C). Then 100 μl of 0.5 mmol/l Val-Leu-Lys-pNA in 2.45 mol/l arginine, pH 8.6, was added and the increase in absorbance with time was measured. The different CLA-PMN assay versions correlated with each other with r = 0.543–0.782. Cellular fibrinolysis (34 ± 30% lysis; normal: 25 ± 10%) did not correlate with the FIPA (72 ± 27%; normal: 100 ± 15%), prothrombin time, activated partial thromboplastin time, fibrinogen, C-reactive protein, or the blood counts of thrombocytes, leukocytes, or polymorphonuclear neutrophils. Chloramine (1.5 mmol/l) oxidation of the microclots favours their fibrinolytic breakdown, especially if lysis-resistant microclots are oxidized. The FIPA and CLA-PMN are new economical tests for the fibrinolytic state in patient blood.