Leukocyte Adhesion Molecule Profiles and Outcome after Traumatic Brain Injury

Abstract

Adhesion molecules have an important role in leukocyte migration into tissue after injury. We hypothesised that changes in ICAM-1 and L-selectin expression after traumatic brain injury would result in altered serum concentrations of these molecules, which would be related to injury severity and outcome. We investigated arterial and jugular venous concentrations of ICAM-1 and L-selectin in 22 patients. The Glasgow Coma Score and Injury Severity Score were recorded. Paired arterial and jugular venous blood samples were taken at designated times after brain injury: on admission, at 24 hours, 48 hours and 96 hours. Glasgow Outcome Scores at 6 months were obtained. Mean serum concentrations of ICAM-1 were normal on admission, but became significantly increased by 96 hours (p = 0.018). Mean L-selectin concentrations were markedly below controls at all time points (p < 0.001). There were no significant differences between jugular venous and arterial concentrations of either ICAM-1 or L-selectin. Serum ICAM-1 was significantly related to neurological outcome (p < 0.001) and to the Glasgow Coma Score (p < 0.001). These changes in adhesion molecule expression may be important in the pathophysiology of secondary injury. The highly significant relationship between serum ICAM-1 and neurological outcome suggests that drugs which antagonize adhesion molecule activity may improve outcome after traumatic brain injury.