ENHANCED POLYMORPHONUCLEAR LEUKOCYTE ADHESION AFTER SURGICAL INJURY

Objective: To evaluate the relationship between the expression of the neutrophil adhesion receptor CD11b, functional neutrophil adhesion, an d clinical outcomes in patients undergoing major surgical resections. Design: Laboratory study. Setting: University hospital, United Kingdom . Subjects: 25 patients undergoing surgical resections for malignant d isease. Interventions: Blood obtained preoperatively and on postoperat ive days 1, 3, and 6. Neutrophils were assayed for CD11b expression in whole blood and following isolation using flow cytometry, and adhesio n was measured using a chromogenic, gelatin-dependent adhesion assay, with and without stimulation by FMLP. Postoperative outcomes were clas sified as uncomplicated (n=20) or sepsis according to ACCP/SCCM defini tions (n=5). Results: Whole blood neutrophil CD11b expression was sign ificantly increased on the first postoperative day and in all patients was significantly higher in the sepsis group (p<0.001, ANOVA). There was a significant increase in CD11b expression above preoperative conc entrations after separation and stimulation with FMLP only in the seps is group, 3 and 6 days postoperatively (p<0.01, paired t-test). Functi onal neutrophil adhesion was significantly higher in the sepsis compar ed with the uncomplicated group at all time points postoperatively (p< 0.001, two way ANOVA). Conclusion: Major operations are accompanied by upregulation of baseline CD11b expression mirrored by changes in neut rophil adhesion. Those patients who develop sepsis have greater degree s of CD11b expression and adhesion. These data present a potential pat hophysiological role for neutrophils throughout the postoperative peri od in the development of sepsis and its sequelae after major operation s.