Leukocyte CD11b and CD18 expression are increased in blood salvaged for autotransfusion

To investigate whether activated leukocytes are present in salvaged blood, we measured complete blood counts and quantified the surface expression of the leukocyte adhesion receptors CD11b and CD18 in salvaged blood and arterial blood from six male patients undergoing elective abdominal aortic aneurysm repair. Salvaged blood contained 5,450 +/- 1010 leukocytes/microL and 7600 +/- 6200 platelets/microL and had a hematocrit of 50.6 +/- 3.7%. CD 11b expression was 3.3 +/- 0.5 fold higher on neutrophils and 3.8 +/- 1.0 fold higher on monocytes from salvaged blood compared with arterial blood (P < 0.05 for both). CD18 expression was increased 3.2 +/- 0.2 fold on neutrophils and 2.5 +/- 0.4 fold on lymphocytes (P < 0.05) in salvaged compared to arterial blood (P < .05). Monocyte expression of CD18 was increased 4.50 +/- 1.1 fold in salvaged blood, but this difference was not statistically significant. We conclude that a substantial number of activated leukocytes are present in salvaged blood. Because activated leukocytes could potentially be detrimental to the recipient, our findings raise theoretical concerns about the use of salvaged blood and emphasize the need for further refinement of the procedure.