Cerebrovascular response in children following severe traumatic brain injury

To describe the pathophysiologic response in cerebral blood flow (CBF) and autoregulation after severe traumatic brain injury (TBI), Glasgow Coma Score (GCS) a parts per thousand currency sign8 on admission, in children, defining a baseline for future studies. Retrospective chart review of 95 patients following TBI, ages 0.1-18.4 years (< 5 years (n = 44), < 2 years (n = 17)) for CBF using Xenon Computerized Tomography (XeCT) over a 10-year period and 6-month Glasgow Outcome Scores (GOS). A total of 140 CBF studies were performed variably from admission up to post injury day (PID) 9; 27 patients underwent repeat CBF study after PaCO2 was manipulated to determine CO2 vasoreactivity (CO2VR). Mean CBF on admission (PID 0, n = 26) was 32.05 +/- 21.45 ml/100 g/min (mean +/- SEM) and was a parts per thousand currency sign20 ml/100 g/min in eight patients. At PID 1-2, mean CBF increased to 55.36 +/- 23.11 ml/100 g/min. There was significant differences in mean CBF of "favorable" outcomes (GOS a parts per thousand yenaEuro parts per thousand 4) versus "unfavorable" outcome (GOS a parts per thousand currency signaEuro parts per thousand 3) (61.74 +/- 18.27 vs. 46.54 +/- 26.26, respectively (P = 0.01)). "Unfavorable" outcomes were seen in all patients with CBF a parts per thousand currency sign20 ml/100 mg/min during PID 0-2 and in 76.5% of children < 2 years. CO2VR < 2%/Torr PaCO2 within PID 0-2 was significantly associated with "unfavorable" outcome (P = 0.029). Younger age, early or later low CBF, and CO2VR < 2%/Torr PaCO2 were correlated with poorer outcomes in children. This represents the largest experience with XeCT CBF in children and confirms our preliminary report of low early CBF after TBI in children, disturbed CO2VR, and relationship of low CBF and unfavorable outcome.