Abstract

Elevation of Neutrophil Elastase Activity in Intra-Operative Recovered Shed Blood

Soichi Maekawa, Kensuke Umakoshi, Satoshi Kikuchi, Hironori Matsumoto, Jun Takeba, Suguru Anen, Naoki Moriyama and Mayuki Aibiki

Background and Aim: Neutrophil elastase releasing from activated polymorphonuclear neutrophils (PMN) may have a central role in acute lung injury. Thus, we examined whether neutrophil elastase activity (NEA), a crucial parameter for organ damages from stresses, may increase in intra-operative recovered blood and also whether the storage duration of the bank bloods may affect such changes in NEA. Methods: In thirty-two packed red cells of bank bloods, NEAs were measured by ELISA on several day points after the storage. Intra-operative salvaged red cell concentrates (RCCs) were obtained from thirteen patients undergoing spinal surgery. The salvaged bloods from the patients were divided into two groups: NE activities in autologous RCCs obtained from eight patients were examined soon after the preparation (Group A); such activities in RCCs from five subjects were determined post-operatively (Group B). Results: In the bank bloods, NEAs gradually increased after the storage, showing a plateau at the day 10 if not specifically filtered leukocytes before the preparation. In Group B, NEA levels in RCCs were significantly higher than those in Group A. In Group B (RCCs stored for four hours), NEAs were nearly two times higher than those of the peak NEA values of the bank blood at the day 21. Conclusion: Thus, we need to pay attention the occurrence of lung injury even after the transfusion of autologous bloods collecting by the intra-operative shed blood recovered system.