Leukocyte activation by means of intraoperative blood salvage

Although clinical experience has shown the safety of intraoperative blood salvage (IBS) to be excellent, the activation of polymorphonuclear leukocytes (PMNL) induced by the preparation process is discussed as a clinically relevant and undesired side effect. Animal experiments and a very few case reports associate the symptoms, namely general edema, ARDS and coagulopathy (salvaged blood syndrome), with the activation of PMNL by IBS. The results of studies investigating concentrations of cytokines, lipid mediators and complement factors show that these undesired substances are reduced by the centrifugation and washing process to an extent considered adequate by most publications. However, only very few data are available on functional responses of PMNL in the IBS concentrate. Excess activation of PMNL by unphysiological priming can be assessed by determining the production of O(2) radicals (respiratory burst). In addition, chemotaxis measurements provide information on the migratory capacity of PMNL, which is also changed by priming. Functional studies demonstrate a reduced to slightly increased respiratory burst in PMNL of the IBS concentrate as compared with measurements in native patient blood as well as a reduced migratory capacity. In agreement with the excellent clinical experience concerning the incidence of serious side effects following IBS, these results show that retransfusion of IBS concentrates containing moderately activated PMNL should not be deleterious for the recipient.