Early immunologic responses to trauma in the emergency department patients with major injuries.

Abstract

A traumatic insult initiates an inflammatory cascade, which is a contributor to cell damage and could be a marker of injury severity. To compare the initial and 4-h post-injury lymphocyte subsets and cytokine levels between patients with minor and major injury. Prospective, cross-sectional study of trauma patients in an urban level I trauma center. Adult patients with significant mechanism of injury requiring admission. cell counts (B-cells, Natural Killer cells, monocytes; and CD4 and CD8 T lymphocytes) and cytokines (IL-1, IL-5, IL-6, IL-10, and TNFalpha). We divided subjects into two groups (major and minor injury). We defined major injury as an injury severity score > or =15, or drop in hematocrit > or =10 points or blood transfusion requirement. Univariate analysis was performed using each inflammatory marker, and multivariate logistic regression analysis was performed to identify the inflammatory markers associated with major injury. 79 patients were studied (mean age: 35+/-17, age range: 13-88, 84% male, 38% penetrating trauma, 96% African-American). 25% of patients (n=20) experienced major injury. Larger base deficit (-3.6+/-6.2 vs. -0.9+/-4.2) levels were observed in major trauma patients. We found that major injury is associated with a drop in absolute CD4 cell count (but not in the CD8 cells), a rise in absolute B-cell count (but not in the NK-cells or monocytes), and a rise in IL-6 (but not in the IL-1, IL-5, IL-10, TNF-a). We found evidence of a measurable early inflammatory response to trauma, using cytokine levels and lymphocyte subset counts.