The aim of the study was to look at the concentrations of pro-inflammatory cytokines and soluble cell surface receptors including tissue factor (TF) in the drainage fluid and in the serum after retransfusion. TF is a membranous glycoprotein from the surface of fibroblasts or smooth muscle cells of vessels that functions as a receptor for the coagulation factor VII/VIIa (Kobayashi 1998)

ELISAs were used in twelfve patients to measure the concentrations of interleukins (IL-1β, IL-2, IL-6, IL-8), tumor necrosis factor-a as well as of soluble cell surface receptors (sIL-2Ra, sHLA-DR) and of TF.

All pro-inflammatory cytokines were released into the drainage fluid at increasing concentrations, IL-6 and IL-8 thereby exceeding postoperative systemic blood levels by 200-fold or 80-fold, respectively. Reinfusion of the collected shed blood led to a further increase in both the IL-6 and IL-8 serum concentrations, which were found to be elevated already postoperatively. sHLA-DR was found in an about 100-fold excess vs. serum. The concentration of TF in the drainage fluid was five times higher (158±71 pg/ml) than in serum. There was no increase of the serum of sHLA-DR or TF levels following the retransfusion.

IL-6 and IL-8 seem to be responsible for potential febrile reactions. The 100-fold elevated concentration of sHLA-DR in shed blood could therefore represent a physiological tissue level. The high TF-levels in the shed blood could be related to a local tissue damage. Dilution effects of fluid retransfused may be responsible for minor or no changes of cytokines, soluble cell surface receptors and TF in the circulation