Associations of initial haemodynamic profiles and neurological outcomes in children with traumatic brain injury: a secondary analysis.

Introduction: Initial low systolic blood pressure (SBP) in paediatric traumatic brain injury (TBI) is associated with mortality. There is limited literature on how other haemodynamic parameters including heart rate (HR); diastolic blood pressure (DBP); mean arterial pressure (MAP); and shock index, paediatric age-adjusted (SIPA) affect not only mortality but also long-term neurological outcomes in paediatric TBI. We aimed to analyse the associations of these haemodynamic variables (HR, SBP, MAP, DBP and SIPA) with mortality and long-term neurological outcomes in isolated moderate-to-severe paediatric TBI.

Methods: This was a secondary analysis of our primary study that analysed the association of TBI-associated coagulopathy with mortality and neurological outcome in isolated, moderate-to-severe paediatric head injury. A trauma registry-based, retrospective study of children <18 years old who presented to the emergency department with isolated, moderate-to-severe TBI from January 2010 to December 2016 was conducted. The association between initial haemodynamic variables and less favourable outcomes using Glasgow Outcome Scale-Extended Paediatric) at 6 months post injury was analysed using logistic regression.

Results: Among 152 children analysed, initial systolic and diastolic hypotension (<5th percentile) (OR) for SBP 11.40, 95% CI 3.60 to 36.05, p<0.001; OR for DBP 15.75, 95% CI 3.09 to 80.21, p<0.001) and Glasgow Coma Scale scores <8 (OR 14.50, 95% CI 3.65 to 57.55, p<0.001) were associated with 'moderate-to-severe neurological disabilities', 'vegetative state' and 'death'. After adjusting for confounders, only SBP was significant (adjusted OR 5.68, 95% CI 1.40 to 23.08, p=0.015).

Conclusions: Initial systolic hypotension was independently associated with mortality and moderate-to-severe neurological deficits at 6 months post injury. Further work is required to understand if early correction of hypotension will improve long-term outcomes.