Correlation between factor (F)XIa, FIXa and tissue factor and trauma severity.
It has been observed that trauma patients often display elevated procoagulant activity that could be caused, in part, by tissue factor (TF). We previously observed that trauma patients with thermal, blunt, and penetrating injuries have active FIXa and FXIa in their plasma. In the current study, we evaluated the effect of injury severity, with or without accompanying shock, on the frequency and concentration of TF, FIXa, and FXIa in plasma from trauma patients.



Eighty trauma patients were enrolled and divided equally into four groups based on their Injury Severity Score and base deficit:Blood was collected at a 0 time-point (first blood draw upon arrival at hospital) and citrate plasma was prepared, frozen, and stored at -80 °C. FXIa, FIXa, and TF activity assays were based on a response of thrombin generation to corresponding monoclonal inhibitory antibodies.



The frequency and median concentrations of TF were relatively low in non-severe injury groups (17.5% and 0 pM, respectively) but were higher in those with severe injury (65% and 0.5 pM, respectively). Although FXIa was observed in 91% of samples and was high across all four groups, median concentrations were highest (by approximately fourfold) in groups with shock. FIXa was observed in 80% of plasma samples and concentrations varied in a relatively narrow range between all four groups. No endogenous activity was observed in plasma from healthy individuals.



(1) Frequency and concentration of TF is higher in patients with a higher trauma severity. (2) Concentration of FXIa is higher in patients with shock. (3) For the first time reported, the vast majority of plasma samples from trauma patients contain active FIXa and FXIa.



Prognostic/epidemiological study, level II.
From the Department of Biochemistry (S.M.P., S.B.), University of Vermont, Burlington, Vermont; and Department of Surgery (M.J.C, A.S.C., M.F.N., L.Z.K., B.M.H.), University of California San Francisco, San Francisco, California.
Shannon M
SM
Prior
Mitchell J
MJ
Cohen
Amanda S
AS
Conroy
Mary F
MF
Nelson
Lucy Z
LZ
Kornblith
Benjamin M
BM
Howard
Saulius
S
Butenas
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015949:Factor IXa / Q000032:analysis*; D015945:Factor XIa / Q000032:analysis*; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D012769:Shock / Q000097:blood; D013925:Thromboplastin / Q000032:analysis*; D014947:Wounds and Injuries / Q000097:blood*; D055815:Young Adult
D013925:Thromboplastin; D015949:Factor IXa; D015945:Factor XIa