ABSTRACT
BACKGROUND: The purpose of this study was to study the temporal changes in circulating phagocyte respiratory burst activity and its relationship to mortality in intensive care unit (ICU) patients. METHODS: Thirty-seven consecutive patients over a 3-week period were studied on their first, third, and seventh day of admission to the regional ICU in Northern Ireland. Blood samples were assayed for respiratory burst activity using luminol-enhanced whole blood chemiluminescence. RESULTS: Compared with survivors, nonsurvivors exhibited significantly higher Acute Physiology and Chronic Health Evaluation II scores, a base deficit, and reduced phagocyte activity (median [interquartile range]) (24.00% [18.00%, 56.00%] vs. 38.00% [30.00%, 63.50%], p = 0.047, Mann-Whitney U test) on day 3 of admission to the ICU. CONCLUSION: Temporal changes in phagocyte activation dependent on the underlying insult were seen in ICU patients. Furthermore, the degree of phagocyte activation was able to distinguish between survivors and nonsurvivors on day 3 of admission to the ICU. Nonsurvivors exhibited reduced phagocyte activation, suggesting patients at risk of mortality exhibit systemic anergy.
