New Frontiers in Pediatric Traumatic Brain Injury

An Evidence Base for Clinical Practice

Cathy Catroppa, Vicki Anderson, Miriam Beauchamp, Keith Yeates

• Publisher: Routledge
• Year: 2016
• ISBN:
  9781135246761
• Edition: 1
• Topic: Psychology
• Subtopic: History & Theory in Psychology
• Index: Psychology

New Frontiers in Pediatric Traumatic Brain Injury provides an evidence base for clinical practice specific to traumatic brain injury (TBI) sustained during childhood, with a focus on functional outcomes. It utilizes a biological-psychosocial conceptual framework consistent with the International Classification of Functioning, Disability and Health, which highlights that biological, psychological, and social factors all play a role in disease and children's recovery from acquired brain injury. With its clinical perspective, it incorporates current and past research and evidence regarding advances that have occurred in outcomes, predictors, medical technology, and rehabilitation post-TBI.

This book is great resource for established and new clinicians and researchers, graduate students, and postdoctoral fellows who work in the field of pediatric TBI, including psychologists, neuropsychologists, pediatricians, and psychiatrists.

1Introduction

DOI: 10.4324/9780203868621-2

Traumatic brain injury (TBI) is a major public health problem among children and adolescents. In fact, TBI represents the leading cause of morbidity and mortality in children and adolescents (Anderson, Catroppa, Morse, Haritou, & Rosenfeld, 2005a) in developed nations. Perhaps because of the significant ongoing costs to not only survivors of TBI, but also their family and the community more generally, interest in TBI has exploded in the past few decades. This interest has led to advances in acute medical treatments. Recent research has focused on, among other things, the reduction of preventable secondary brain insult via faster medical response, potentially predictive biomarkers for early detection of injury, and interventions such as hypothermia. Advances in brain imaging have assisted in early diagnosis of TBI and helped guide appropriate treatment, with current high-resolution imaging enabling the identification of even subtle brain damage in the context of mild TBI. Evidence from both structural and functional imaging technologies increasingly shows common patterns of brain pathology resulting from pediatric TBI, both macroscopic and microscopic, and changes that occur over time in response to damage to the developing brain.

Researchers have also been reasonably successful in describing the longer-term consequences of child TBI, especially more serious injuries. The natural history of child TBI has been studied extensively, and we now have a working understanding of the acute and long-term effects of injury for the child and family. The next step is to translate empirical findings into clinically relevant information in order to develop, improve, and appropriately target evidence-based approaches to facilitate better outcomes for the child and family.

There are, however, several very real obstacles, many of them specific to this particular population. To begin, child TBI has not attracted the public attention that other childhood disorders receive, possibly because the consequences of TBI are often “masked,” with most children appearing “normal” after injury, despite suffering from functionally significant impairments. An additional complication is that children who suffer TBI are not representative of the healthy population; they are more likely to have pre-existing behavioral and learning problems, as well as social disadvantages (Taylor & Alden, 1997). These factors may negatively affect recovery, as well as confound our ability to determine which post-injury difficulties are due to TBI and which might have predated the injury.

This book aims to contribute to knowledge about child TBI and its relevance to clinical practice. We have chosen to place particular emphasis on understanding of children's post-injury function, recovery, and outcomes, as well as factors that help predict recovery at the individual level. In order to achieve this goal, the book is divided into four sections: i) epidemiology and physiology of child TBI; ii) developmentally appropriate measurement and assessment considerations; iii) a comprehensive description of the functional consequences of child TBI and the factors that contribute to them; and iv) a review of evidence-based management and treatment approaches.

Epidemiology and Pathophysiology of Child TBI

Epidemiological data demonstrate that one in every 20 emergency department presentations at pediatric hospitals is for a TBI, making TBI more common than burns or poisonings. In the context of infancy, childhood, and adolescence, such injuries represent a common interruption to normal development, with population estimates ranging from 200 to over 500 per 100,000 a year and with well-established variations across age and gender (Crowe, Babl, Anderson, & Catroppa, 2009; Langlois, Rutland-Brown, & Thomas, 2006). Fortunately, the majority of TBIs sustained by children and adolescents are mild, typically with few long-term consequences; however, a significant proportion of children will experience a range of residual and persisting physical, cognitive, educational, functional, social, and emotional consequences. These children and adolescents will require lifelong health care across a range of disciplines, leading to a significant social and economic burden for the children's families and for the community more broadly (Cassidy, Carroll, Peloso, Borg, et al., 2004).

Further, research has established that the mechanisms of injury often vary with developmental stage. For example, injuries due to child abuse are almost exclusive to infants, whereas in preschool children, the majority of injuries occur as a result of falls from furniture or play equipment. These early injuries are likely to be linked closely to environmental factors, such as family dysfunction and social disadvantage. In contrast, in older children, injuries are more likely to be due to sporting or motor vehicle accidents and can be more directly associated with the child's own actions and behavior. In light of these epidemiological data, communities are beginning to take steps to educate people about and prevent TBI. For example, in some countries, helmets have been mandated for bicycle riders and participants in certain contact sports.

Developmental Considerations

In recent decades, researchers and clinicians working with children with TBI have become aware that children are not simply “little adults” and that injuries to the immature brain cannot be understood or treated in the same manner as adult injuries. In fact, evidence increasingly indicates that age and skill attainment at the time of injury are important considerations in assessing the impact for neural networks and the likelihood of recovery. Although the field of child TBI is largely guided by science and practice in adult TBI, developmental and contextual issues need to be taken into account at all stages of recovery and treatment. Until relatively recently, our understanding of recovery and outcomes following child TBI lagged behind that for adults. This is changing. Research in child TBI has grown enormously and now has more solid foundations. Key principles have been established, some of which are consistent with the adult literature, such as the predictive value of injury severity (Anderson, Morse, Catroppa, Haritou, & Rosenfeld, 2004; Taylor, Swartwout, Yeates, Walz, et al., 2008). Others are child-specific—for example, the unique mechanics and characteristic pathology of inflicted injury in children (Coats & Margulies, 2006; Prange & Margulies, 2002)—or reflect the importance of developmental and contextual factors, such as the child's age at injury, stage of brain development, and functional maturation (Anderson, Catroppa, Morse, Haritou, & Rosenfeld, 2005b; Taylor & Alden, 1997); the key role of the family; and implications of life tasks specific to children (Yeates, Taylor, Drotar, Wade, et al., 1997).

Outcomes of Child TBI

To begin, in recognition of the very different acute consequences and later recovery trajectories associated with mild (that is, concussion, mild, and mild complicated) and more serious (moderate to severe) child TBI, we have separated our discussion of the literature relevant to each throughout the book.

Although some controversy remains, research has demonstrated that children with milder injuries are likely to recover well, with few residual problems. With increasing severity, recovery is less complete, and we know that those with severe injury are at risk for ongoing difficulties across a range of domains and that these difficulties may persist into adulthood (Hessen, Nestvold, & Anderson, 2007; Jaffe, Polissar, Fay, & Liao, 1995; Yeates, Swift, Taylor, Wade, et al., 2004).

Research findings, from a range of mostly discipline-specific research endeavors, describe an increased risk for a multitude of residual impairments following childhood TBI, both acute and long-term. Persisting neurological symptoms, motor dysfunction, communication difficulties, poor attention and information processing, reduced memory, executive dysfunction, and social and emotional disorders have been consistently reported for many children with serious TBI. In association with these impairments, functional outcomes are also affected, with solid evidence of low academic achievement, reduced vocational opportunities, poor adaptive skills, and lowered quality of life.

There remains a significant challenge for the direct application of these research-based findings, with clinical reports confirming that outcomes are highly variable and difficult to predict, leading to uncertainty with respect to prognosis and need for follow-up and treatment. For example, anecdotal clinical reports describe excellent recovery after severe TBI in some children. In contrast, emerging trends in the child concussion literature suggest that a subset of young people will experience delayed recovery, characterized by persistent and debilitating symptoms that affect participation in school and social activities and quality of life.

More precise information is critical to determine which children are at high risk for poorer outcomes and to effectively allocate management and treatment resources. To date, research has been only modestly successful in providing guidance with respect to which factors contribute most to recovery and positive outcomes. Much research on child TBI has focused on specific domains. For example, medical researchers may examine the impact of raised intracranial pressure or neurological signs on long-term outcomes, whereas others may look at specific biochemical markers, radiological results, or environmental factors. The fact that progress using such a narrow focus has been disappointing suggests that a more multi-dimensional model is required, in which researchers across disciplines come together with a more holistic view of the child, recognizing the likelihood that factors across multiple dimensions (e.g., injury, environment, developmental stage) interact to determine eventual outcomes. In support of this, emerging research suggests that the search for globally relevant markers of outcome may not be fruitful; rather, there may be differing markers for outcomes across specific domains. For example, injury factors may predict physical and cognitive recovery, whereas environmental factors may be more closely linked to behavior and socio-emotional outcomes.

Management, Treatment, and Intervention

A further challenge exists in the area of management and treatment. At present, evidence for effective treatment, at both acute and more long-term stages of recovery, is largely lacking across medical, pharmacological, cognitive, and behavioral domains (Anderson & Catroppa, 2006; Laatsch, Harrington, Hotz, Marcantuono, et al., 2007; Robinson, Kaizar, Catroppa, Godfrey, & Yeates, 2014; Ylvisaker, Adelson, Willandino Braga, Burnett, et al., 2005). As a result, health professionals have little direction with respect to which interventions may lead to better outcomes. Reflecting this problem, clinical practice guidelines, where established, vary dramatically across the world, and even within individual centers. Care pathways are disparate, and clinical decisions are typically based more on previous training and experience than on empirical grounds. Treatment research and clinical trials in this domain are costly and difficult, but they are critical to improving child outcomes.

A Bio-Psycho-Social Model of Child TBI

To understand child TBI and its outcomes, we suggest a developmentally driven “bio-psycho-social framework,” integrating biological, neurobehavioral, and psychosocial/environmental dimensions, all of which contribute to the child's recovery from TBI. With respect to the biological dimension, initial brain insult due to TBI results in interruptions to cerebral circulation, changes in intracranial pressure, loss of tissue, and disruptions in neural networks. Such damage is associated with a characteristic set of psychological deficits in attention and memory, information processing, executive function, communication, and behavior and social skills, whether due to the direct effects of brain injury or as a “secondary consequence”—a consequence of adapting to the consequences of TBI (e.g., physical limitations, response to trauma). The quality of the child's environment, including family function, stress, and coping, as well as access to resources, has been identified as critical to long-term outcomes.

Of crucial importance is growing evidence for a developmentally specific response to injury, demonstrating that knowledge and theories regarding adult TBI cannot be simply translated to the child population. The relative vulnerability of the young brain to the impact of TBI and the increased behavioral consequences in terms of reduced skill and knowledge acquisition is a relatively new concept but is already supported by animal research, neuroimaging data, and behavioral findings. Over time, and in the context of ongoing development, cumulative problems may emerge. For instance, child TBI may lead to an interruption or deviation in normal developmental processes, both at a neuroanatomic level and at a neurobehavioral level. At the same time, the child's psychological function may become increasingly problematic, due to his or her failure to acquire appropriate cognitive, behavioral, and social skills. Such failure may hamper knowledge acquisition and consolidation while increasing social isolation and associated family stresses. The long-term consequences of these multiple and interacting factors may result in a picture of global dysfunction. This view is supported by an emerging literature that describes adult survivors of child TBI as experiencing academic failure, restricted vocational options, psychological adjustment difficulties, and poor quality of life (Anderson, Brown, Newitt, & Hoile, 2011; Cattelani, Lombardi, Brianti, & Mazzucchi, 1998; Di Battista, Godfrey, Soo, Catroppa, & Anderson, 2014; McKinlay, Dalrymple-Alford, Hoorwood, & Fergusson, 2002). The child's need to acquire new skills and knowledge and meet educational demands, in the context of increased risk of physical, cognitive, and behavioral impairment, generates unique challenges for rehabilitation and reintegration following TBI. Appropriate and timely intervention and follow-up, for both child and family—based on knowledge of the disorder, its symptom-atology, and likely outcomes—may prevent such poor prognosis and enable the child and family to understand and successfully manage these problems.

As mentioned above, research on child TBI has often occurred in separate silos, with little integration across domains or disciplines. The scientific advances that have occurred within domains (e.g., genomics and proteomics of neural recovery, neuroimaging, neuropsychology) are unlikely to result in significant progress in the clinical management of children with TBI until such advances become the topic of collaborative research that cuts across levels and specialties. In the field of TBI, we can learn much from the study of other childhood disorders, such as childhood cancer, where international collaborative consortia have been in existence for many years and have led the way in developing and implementing evidence-based, life-saving treatment protocols that have reduced mortality rates from 70% (in the 1970s) to close to 10% (in the past decade).

Conclusions

The time seems ripe for an interdisciplinary and collaborative approach to pediatric TBI that promotes integrative and translational research efforts. We believe that this book, New Frontiers in Pediatric Traumatic Brain Injury: An Evidence Base for Clinical Practice, will help advance the state-of-the-art of research in the field and promote networking and collaboration among investigators. The chapters that constitute the book describe the state of the art in resear...

Table of contents

• Cover Page
• Half Title Page
• Series Page
• Title Page
• Copyright Page
• Table of Contents
• About the Authors
• Acknowledgments
• Preface
• 1 Introduction
• Section I Epidemiology, Mechanisms, and Pathophysiology of Child TBI
• Section II Measurement and Assessment of Child TBI
• Section III Evidence-Based Outcomes and Their Predictors Following Child TBI
• Section IV Rehabilitation/Intervention
• References
• Index