Cytokine and coagulation characteristics of retrieved blood after arthroplasty

Objectives: To investigate cytokine and coagulation/fibrinolysis characteristics in blood retrieved from wounds using an autotransfusion system, and to compare the cytokine pattern in the retrieved blood with those in the systemic circulation and in the initial portion of drainage blood from the wound. Design: Prospective controlled clinical study. Setting: The postoperative ward of a University hospital. Patients and participants: Blood retrieval was performed over a period of 4-6 h on patients who had just undergone arthroplasty (nine hips, one knee). In five other cases involving hip arthroplasties, the initial portion of drainage blood was studied. Measurements and results: Coagulation/fibrinolysis parameters were analyzed in blood retrieved using the Stryker Consta Vac system. Concentrations of tumor necrosis factor alpha (TNF), interleukin-1 beta (IL-1) and interleukin-6 (IL-6) were analyzed in the retrieved blood, in the systemic circulation of the patients at the beginning and at the end of blood retrieval and in the initial portion of drainage blood from the surgical area. In the retrieved blood, the activities of thrombin, kallikrein and plasmin were increased, antithrombin and free protein S were decreased, and in all samples IL-6 was > 1000 pg/ml. Postoperative plasma concentrations of IL-6 rose from a median value of 0 to 116 pg/ml (p<0.01). Four patients had circulating TNF concentrations (range: <15-50 pg/ml). Plasma IL-1 was not detected. TNF and IL-1 were detected in all samples of initial blood from the surgical area and IL-6 in one sample. Conclusion: Hypercoagulability and high concentrations of IL-6 were present in the retrieved blood. The cytokine pattern in the initial portion of blood from the surgical area differed from those in the retrieved blood and in the systemic circulation.