Comparing the systolic blood pressure (SBP) and pulse rate (PR) in injured children with and without traumatic brain injury

Aims: Following evidence that injured children have higher systolic blood pressures (SBP) than similar-aged resting uninjured children, we investigate whether the initial cardiovascular physiology differs between forms of injury.

Methods: Analysis of prospectively recorded data from the Trauma Audit and Research Network (TARN) database of injured children aged <or=15, presenting with blunt trauma from March 1988 to February 2009. We compared the ED arrival SBP and pulse rate (PR) in children with and without TBI. The analysis was stratified by age and injury severity (ISS<or=8=mild, ISS 9-14=moderate, ISS>or=15=severe) through medians, graphs and compared through analysis of covariance.

Results: Data for 18,135 children were analysed. Those with TBI had a higher mortality rate (17.2%) and were more severely injured. No difference was seen between the two groups in the SBP of severely injured children (p=0.09) who were almost all hypertensive compared to APLS "norms". Further analysis revealed a significant difference in the PR of severely injured children (p<0.001), attributed to children <9 years of age with brain injuries showing lower heart rates than those with extracranial injuries, though all still within the normal range for their age.

Conclusions: Although injured children remain hypertensive as compared to resting norms, we have seen no difference in the initial systolic blood pressure of moderately and severely injured children with and without traumatic brain injury. The relative bradycardia in the younger children appears to be an early sign of a severe traumatic brain injury.