Prediction Of Brain Injury Research Articles

Selection of babies for intervention after birth asphyxia

Based on animal experiments, the therapeutic window for neonates with signs of perinatal hypoxia-ischaemia is probably less than 6h, and early selection of patients is of utmost importance. In term neonates, fetal heart rate and blood flow patterns, the Apgar score, and other clinical scoring systems are insufficient to select patients for intervention, whereas umbilical artery pH<7.0 combined with umbilical arteriovenous differences in Pco2, lactate/pyruvate ratios in cord blood, and CSF interleukin-1β have a better predictive value. At present, neurophysiological methods such as (amplitude-integrated) EEG and evoked potentials have the best predictive value. In preterm neonates, lactate/pyruvate and uric acid measurements in cord blood, as well as neurophysiology appear to be helpful to predict brain injury, and might be used to select patients for intervention.

Maturation of the flash visual evoked potential in preterm infants.

Flash visual evoked potentials (VEPs) were recorded from 67 infants of < 33 weeks gestation with normal neurological outcome at 24 months corrected age. Cross sectional and longitudinal data showed the emergence of peak components of the waveform with increase in maturity. The first major negative peak, with a latency around 300 ms in the most immature subjects, was the most prominent and consistent component. This peak showed a decrease in latency with increase in post-conceptional age, maturing by a mean rate of 5.5 ms/week. The role of VEPs in predicting brain injury in preterm infants can be determined.

Parameter estimation for head impacts and brain injury in crash reconstruction

Abstract An alternative to detailed and complex mathematical reconstruction of head impacts is to use a well-justified simple estimation method with known error potentials. The Pedestrian Head Injury Calculation (PHIC II) model was derived from a simple method developed at the NHMRC Road Accident Research Unit of the University of Adelaide. This model utilises basic data from each crash investigation, the autopsy and carefully chosen and tested parameter relationships. The PHIC II model was used to establish peak angular acceleration and maximum angular velocity change parameters for head impacts at differing impact velocities, head-vehicle impact stiffnesses, and impact offsets. The potential brain injury severity of these impacts was evaluated from a brain shear strain model. It was found that for impacts with a head-vehicle stiffness greater than about 130 kN/m the only effective way to reduce brain injury severity is to reduce the head impact velocity while for impacts with a stiffness less than 130 kN/m both stiffness and head impact velocity will have an effect on the severity of the brain injury. At stiffnesses around 130 kN/m there appears to be a change in injury mechanism related to the natural frequency of the brain skull system. Both the PHIC II and the shear strain models correctly predict brain injury in actual pedestrian head impacts. The results of this study suggest that the PHIC II model works well as a simple field analysis method.