Long-term outcome of pediatric head injuries – A five-year follow-up

INTRODUCTION

In the pediatric population, traumatic brain injuries (TBIs) can disrupt the process of development and interfere with behavioral adjustment, knowledge acquisition, and learning new skills.^[1] Despite the commonly held view that the pediatric brain has the ability to adapt to the insults sustained, several studies have demonstrated the presence of residual damage.^[2,3]

Studies have suggested that in the younger population, structural damage and functional deficits are less compared to older patients , as the non damaged adjacent segments take up the functions over time. However, the principles at work in the setting of a more diffuse injury are not yet elucidated.^[4-6] A counterpoint suggests that injuries disrupting the immature neural systems lead to cumulative deficits and children, with a limited established skills, may have difficulty in not just consolidation of these skills but also in acquiring new skills.^[7]

Several factors have been studied to be associated with outcomes. The most significant of these is the severity of the injury. Other factors influencing outcome include age at the time of injury, pre-injury status, the socio-economic status of the parents, and access to rehabilitative care. ^[1,8] Very few studies look at the long-term effects of trauma on the pediatric population in India. This study aims to look at the outcomes of moderate and severe TBI over a five-year follow-up to look for the long-term sequelae of head injury in the pediatric population.

MATERIALS AND METHODS

A prospective observational study was conducted after obtaining the permission of the Institutional Ethics Committee with the primary study participants admitted between 2015 and 2017 with follow-up extending up to 2022 in 118 pediatric patients, aged between 1 and 15 years, who required admission in the pediatric intensive care unit (PICU) with moderate and severe TBI.

RESULTS

DISCUSSION

A multitude of factors determines the long-term outcome of patients with pediatric TBI. The most significant predictor of outcome is the severity of the injury sustained.^[10] The generally noted pattern of recovery is the gradual improvement over the first 12 months in the general intellectual ability of the child. Subsequent trajectories of recovery vary between children, who sustained an injury earlier and those with a later injury. The children with an early injury tend to have a poor prognosis while relatively older children make better recoveries.^[8]

Studies in India have shown that boys were more commonly affected, and falls and road traffic accidents were the most common causes of TBI. In pediatric patients, acute EDH was the commonest radiological finding while loss of consciousness and vomiting were the most common presenting complaints in studies by Bhargava et al. and Chaitanya et al.^[11,12] Both studies also noted a male preponderance. Chaitanya et al. noted that twenty-one percent of patients in their study had seizures. They noted that 31.6% of patients needed mechanical ventilation.^[12] Madaan et al. noted that fractures of the skull were the most common radiological finding followed by EDH. While these findings are in line with the results of our study, they noted only 10.5–12.5% needing surgery^[12,13] compared to the 48% noted in our study. The difference could be accounted for by the inclusion of only moderate and severe head injuries in our study while they had included mild head injuries as well. Besides, since ours is a tertiary referral center, we tend to have patients referred specifically for surgical intervention. These factors could account for the high proportion of surgeries in our study.

Contrary to previous beliefs that the young brain, being more “plastic,” could recover better from injury, various lines of evidence now indicate that children, who experience injuries early in life are more susceptible to long-term deficits.^[8] Children coming from socially disadvantaged groups, lower socio-economic strata, and rural areas are noted to have poor outcomes.^[8,11,12] We noted that the outcome of those, who sustained injuries younger were considerably poorer than their older counterparts.

Several studies^[14,15] have noted that the functional outcome is generally favorable in a majority of the patients at around 50–70%. Correlation between poor outcome and GCS, coagulopathy, sepsis, and need for mechanical ventilation and younger age have been noted by several authors.^[8,10,11] Similar findings were noted in our study. Deficits of attention depend not only on the location of the injury but also on the stage of development the child is in at the time of insult.^[16] Studies have shown skills emerging at the time of injury are affected more.^[17] It has been shown that except in very severe injuries, impaired memory usually shows improvement. Given how even then the memory problems are only for complex memories, memory shows fairly good recovery.^[8,16]

The impact of TBI on the subcomponents of executive function (working memory, cognitive flexibility, and inhibitory control) in children can vary based on factors such as age at injury, injury severity, and ongoing neural and cognitive development. Severe injuries generally lead to weaker executive skills compared to milder injuries. The age at which the injury occurs is crucial for recovering from executive impairments since the frontal lobes, essential for developing these skills, undergo an extended developmental process until late adolescence/early adulthood, marked by neural growth and myelination periods aligning with improved cognitive function.^[18] We noted that less than half of our patients showed improvement in executive function over five years.

Numerous studies have examined functional and pragmatic language impairments following head injury. These impairments can hinder children’s effective communication in day-to-day situations, leading to social challenges. The difficulties may arise from struggles in understanding abstract or metaphorical language and humor, as highlighted by Turkstra et al.^[19] More than a third of the patients, who were followed up for five years had impairment of language function while all of them showed improvement of language function for follow-up.

Some issues arise as a consequence of untreated emotional and behavioral issues directly as a result of the injury, while others may result from impaired skills such as executive dysfunction or inadequate communication skills.^[2] Growing evidence also suggests deficits in certain aspects of social cognition, leading to reduced social competence. Such difficulties were commonly seen in our study participants, who seemed to show marginal improvement with time. Individuals with childhood TBI may struggle with attributing intent and making inferences about the mental states of others, demonstrated by challenges in the theory of mind, as observed in studies like those by Snodgrass and Knott^[20] and Walz et al.^[21]

Our study is limited by the fact that it is a single-center study with the limitation of sample size. Although not many studies have addressed the issues studied here, we hope to continue this study for the foreseeable future to have a longer duration of the assessment and more patients.

CONCLUSION

A complex interplay of factors influences recovery after childhood TBI, making outcomes unpredictable and highly variable. Cognitive impairments are influenced by factors such as age at the time of injury, location as well as severity of the injury.

Our study indicates that over the passage of time, children tend to have a reasonable chance at recovery, and with the potential for plasticity, early and aggressive rehabilitative services may enable the child to have a decent quality of life and in selected cases, even an independent life.