practical management of

HEAD AND NECK INJURY

practical management of HEAD AND NECK INJURY

Edited by Jeffrey V Rosenfeld

Sydney Edinburgh London New York Philadelphia St Louis Toronto

To Joe, Lorraine, Deborah, Alexander, Hannah and Gabriella

© 2012 Elsevier Australia

This publication is copyright. Except as expressly provided in the Copyright Act 1968 and the Copyright Amendment (Digital Agenda) Act 2000, no part of this publication may be reproduced, stored in any retrieval system or transmitted by any means (including electronic, mechanical, microcopying, photocopying, recording or otherwise) without prior written permission from the publisher.

Every attempt has been made to trace and acknowledge copyright, but in some cases this may not have been possible. The publisher apologises for any accidental infringement and would welcome any information to redress the situation.

This publication has been carefully reviewed and checked to ensure that the content is as accurate and current as possible at time of publication. We would recommend, however, that the reader verify any procedures, treatments, drug dosages or legal content described in this book. Neither the author, the contributors, nor the publisher assume any liability for injury and/or damage to persons or property arising from any error in or omission from this publication.

National Library of Australia Cataloguing-in-Publication Data

Author: Rosenfeld, Jeffrey.

Title: Practical management of head and neck injury / Jeffrey Rosenfeld.

ISBN: 9780729539562 (pbk.)

Subjects: Head – Wounds and injuries – Treatment. Neck – Wounds and injuries – Treatment.

Dewey Number: 617.51044

Publisher: Luisa Cecotti Developmental Editor: Neli Bryant Publishing Services Manager: Helena Klijn Project Coordinator: Geraldine Minto Edited by Carol Natsis Proofread by Forsyth Publishing Services Cover and internal design by Darben Design Index by Cynthia Swanson Typeset by Toppan Best-set Premedia Limited Printed by • •

Churchill Livingstone is an imprint of Elsevier

Elsevier Australia. ACN 001 002 357 (a division of Reed International Books Australia Pty Ltd) Tower 1, 475 Victoria Avenue, Chatswood, NSW 2067

v

Contents

Foreword vii

Preface viii

Acknowledgments x

Contributors and reviewers xi

1 Epidemiology 1Russell L Gruen

2 Anatomy of the head and neck 10Tony Goldschlager, Jeffrey V Rosenfeld

3 Pathophysiology of traumatic brain injury 39Tony Goldschlager, Jeffrey V Rosenfeld

4 Pre-hospital management 56Stephen Bernard

5 Emergency department management 63Jeffrey V Rosenfeld, Mark Fitzgerald, Alfredo Mori, David Morgan, Vince Cousins, Anthony Hall

A. Initial treatment and assessment 63Mark Fitzgerald, Alfredo Mori, Jeffrey V Rosenfeld

B. Maxillofacial injuries 80David Morgan, Jeffrey V Rosenfeld

C. Blunt injury of the neck 84Vince Cousins, Jeffrey V Rosenfeld

D. CSF rhinorrhoea 85Vince Cousins, Jeffrey V Rosenfeld

E. Epistaxis 85Vince Cousins, Jeffrey V Rosenfeld

F. Injuries to the ear 87Vince Cousins, Jeffrey V Rosenfeld

G. Fractures of the temporal bone 88Vince Cousins, Jeffrey V Rosenfeld

H. Eye injuries 92Anthony Hall, Jeffrey V Rosenfeld

6 Injury to the spine and spinal cord 97

A. Spinal injury 97Susan M Liew, Arvind Jain

B. Traumatic spinal cord injury 122Jin W Tee, Jeffrey V Rosenfeld, Patrick Chan

7 Vascular injury 135

A. Blunt carotid and vertebral artery injuries 135Jeffrey V Rosenfeld, Jin W Tee

B. Traumatic caroticocavernous fi stula 140Peter Hwang, Anoop Madan

C. Penetrating injury to the cervical carotid and vertebral arteries 147Jeffrey V Rosenfeld, Jin W Tee

8 Operative surgery 149

A. Neurosurgery 149Jeffrey V Rosenfeld

B. Ear, nose and throat (ENT) surgery 175Vince Cousins

C. Ocular injuries 179Anthony Hall

D. Maxillofacial injuries 180David Morgan

E. Cervical spine injuries 193Susan M Liew, Arvind Jain

9 Intensive care management of head injury 211Andrew Davies, D James Cooper, Jeffrey V Rosenfeld

vi CONTENTS

10 Ward care of the head-injured patient 222Peter Hwang, Jin W Tee, Antoinette David

11 Rehabilitation following traumatic brain injury 230John Olver, Bianca Fedele

12 Head injury in children 241Jeffrey V Rosenfeld, Simon Young

13 Head injury in the elderly 253Peter Hwang, Jin W Tee, Jeffrey V Rosenfeld

14 Head injury in sport 262Gavin A Davis, Michael Makdissi, Paul McCrory

15 Penetrating head injury 280Rocco Armonda, Randy S Bell, Jeffrey V Rosenfeld

16 Bleeding diathesis and anticoagulants 293Peter Hwang, Mark Seifman, Jeffrey V Rosenfeld

17 Neurotrauma in pregnancy 302Jeffrey V Rosenfeld, Jin W Tee

18 Brain death 310Alvin Teo, Andrew Davies

19 Persistent vegetative and minimally responsive states following head injury 316Bruce Day

20 Prediction of outcome and the prognosis of head injury 326Lucia M Li, Mathew R Guilfoyle, Peter Hutchinson

21 Prevention of head injury and the role of trauma systems 353Biswadev Mitra, Russell L Gruen

Appendixes 361

A Glasgow Coma Scale 362

B Paediatric Glasgow Coma Scale 362

C Glasgow Outcome Score (Extended) 362

D Marshall CT Grading 362

E Injury Severity Score 363

F American Spinal Injury Association (ASIA) Scale for Acute Spinal Cord Injury Assessment 364

G Westmead Post-traumatic Amnesia (PTA) Scale 366

H Disability scales: short-form 12 (SF-12) 369

I Alfred Cervical Spine Clearance Protocol for Trauma Patients 371

J Post-traumatic amnesia screening and referral process 372

K Essential surgical instruments for emergency neurosurgery 374

L Guidelines bibliography 374

(i) Evidence-based guidelines 374

(ii) Mild traumatic head injury guidelines 374

Index 375

viii

Preface

Globally, it has been estimated that at least 10 million people each year suffer a traumatic brain injury (TBI) that results in death or hospitalisation, and an estimated 57 million people worldwide have been hospitalised with one or more TBIs. Even in trauma systems with advanced pre-hospital and in-hospital medical care, 50% of patients with severe TBI either die or survive with severe lifelong dis-ability. Most of the severe disability survivors are young males who are never able to live indepen-dently or return to employment. There are also many children and elderly people who suffer TBI. Sport and leisure activities are an important cause of TBI in young people. Penetrating brain injury sustained in war zones and because of urban crime is also a major problem worldwide. Acute spinal cord injury, facial, ocular, auditory and cervical vascular injury further contribute to the overall injury burden.

The cost of severe TBI in Australia in economic terms has been independently calculated recently by Access Economics to be A$4.8 billion annually. This does not describe the human cost. In the USA, the economic burden of TBI is estimated to be US$60 billion annually. Imagine the cost to nations and families where trauma systems and medical care are not well developed or resourced, and consider the incalculable worldwide economic burden of brain and spinal cord injury, particularly in low- and mid-dle-income countries. These sobering statistics can be improved through education of health providers, better trauma systems, high quality hospitals and ongoing basic and applied research.

Helping to save lives and improve the outcome of those affected by head and neck trauma is the aim of this book. Practical management of head and neck injury is written for the broad audience of medical students, junior doctors and doctors in specialist training in emergency medicine, neuro-surgery, trauma and general surgery, orthopaedics, otorhinolaryngology, ophthalmology, rehabilitation medicine, neurology and intensive care, and con-tains sections written by experts in all of these spe-cialties. We believe it will also be of interest to paramedics, nurses, physician assistants and allied health professionals. Many chapters will also inform

practitioners who work in remote locations where there is no neurosurgical service.

Why head and neck? A myriad of textbooks on head injury have been published in the last two decades. Many are encyclopaedic, but mainly con-fi ned to the brain and skull. However, injuries to the brain and skull also frequently involve the face and sinuses, mouth, teeth and jaws, orbits, eyes, ears and neck, including the great vessels, spine, spinal cord and pharynx, larynx and trachea. A more holistic approach is required. The interplay between the various specialties is highlighted and should encour-age the multidisciplinary team approach to caring for these patients.

Practical management of head and neck injury captures the essence of the day-to-day management of head and neck injury by following all aspects of care through the patient ’ s journey from the acci-dent scene all the way through to rehabilitation. Separate chapters are devoted to specialised topics covering children, the elderly, pregnancy, coagula-tion disorders, brain death, persistent vegetative state, head injury in sport and penetrating head injury. These are all pertinent problems that junior staff may encounter and with which they should have some familiarity. The management of head and neck injury also depends on a sound understanding of the essential anatomy, including CT images, as well as the pathophysiology. The general issues of epidemiology, prognosis of TBI, prediction of outcome, head injury prevention and trauma systems complete the coverage. The recent pertinent scien-tifi c evidence and discussion of many controversies are also included.

We have assembled a group of authors who are all experts in their respective specialties. While many who write about the patient ’ s journey all work together at the Alfred Hospital and Monash University in Melbourne, Australia, other Australian and international authorities are included.

I make no apologies for not structuring the many varied chapters the same way. I intentionally gave the authors some latitude in how they presented their material and how many references were cited. Despite this, the authors have managed to write in

ixPREFACE

a similarly engaging way for each topic with an appropriate weighting of literature review. There is inevitable overlap between some of the chapters. This has been accepted to maintain the integrity of each of these chapters and to reinforce important concepts.

It is my fervent hope that this textbook will help to improve the knowledge base and interdisciplinary team approach to the management of head and neck

trauma at all types of healthcare facilities and in the full range of healthcare systems, including low-income countries, where services are sparse and generalists do the best they can with limited resources.

Jeffrey V Rosenfeld Melbourne

August 2011

x

Acknowledgments

I owe a debt of gratitude to my own neurosurgical teachers and mentors Mr JB Curtis, Mr D Brownbill and Professor Andrew Kaye at the Royal Melbourne Hospital, Mr CBT Adams and staff at the Radcliffe Infi rmary in Oxford, Dr John Little MD and staff at the Cleveland Clinic, Ohio, and many others too numerous to name. I wish to thank Professor Sir Graham Teasdale, one of the world ’ s leading experts in traumatic brain injury research and management, for writing the Foreword.

I thank the neurosurgery registrars at the Alfred Hospital, Dr Jin Wee Tee, Dr Tony Goldschlager as well as my neurosurgical colleagues at the Alfred, Clinical Associate Professor Peter Hwang and Mr Patrick Chan, for their support and contribution to the book. I also thank my many Alfred colleagues and the other Australian and international contri-butors very much for sharing their tremendous knowledge and experience. I admire US military neurosurgeons Dr Rocco Armonda MD and Dr Randy Bell MD for the devotion they have shown and the expertise they have developed in improving the outcomes for victims of bomb blast and penetrat-ing brain injury.

I particularly wish to thank Associate Professor Max Esser, Senior Orthopaedic Surgeon at the Alfred Hospital and Monash University for encour-aging me to produce this book. He has co-authored Practical Fracture Treatment with Dr Ronald McRea, also published by Elsevier, which is argu-ably one of the defi nitive current textbooks on frac-ture management.

I am indebted to Elsevier for having confi dence in the aim and conceptual design of this textbook. The superb staff at Elsevier, Ms Neli Bryant, Ms Sophie Kaliniecki and Ms Geraldine Minto, and editor Ms Carol Natsis have been enthusiastic, gra-cious and always very obliging in nurturing this text to its fi nal form. I sincerely thank my personal assis-tant, Ms Sylvia Oklobdzija, for all her tremendous assistance.

Last but by no means least, no words can convey the deep appreciation I have for the tremendous love and support I receive from my wife Debbie and my family.

Jeffrey V Rosenfeld

xi

CONTRIBUTORS Rocco Armonda MD, COL, MC Assistant Professor of Surgery, Uniformed Services University of the Health Sciences Director, Cerebrovascular Surgery/Neurocritical Care, Bethesda, Maryland, USA

Randy S Bell MD, MC National Naval Medicine Center, Bethesda, Maryland, USA

Stephen Bernard MBBS, MD, FACEM, FCICM Associate Professor, Intensive Care Physician, The Alfred Hospital, Melbourne, Victoria Director of Intensive Care, Knox Private Hospital, Melbourne, Victoria

Patrick Chan MBBS(Melb), MD(Melb), FRACS Neurosurgeon, The Alfred Hospital, Melbourne, Victoria

D James Cooper BMBS, MD, FRACP, FCICM Professor of Intensive Care Medicine, Monash University, Melbourne, Victoria Director of the ANZIC Research Centre, Monash University, Melbourne, Victoria Deputy Director of ICU, The Alfred Hospital, Melbourne, Victoria Head of Intensive Care Unit (ICU) Research, The Alfred Hospital, Melbourne, Victoria

Vincent Cousins BMedSci(Hons), MBBS(Hons), FRACS Adjunct Clinical Associate Professor, Ear Nose and Throat Surgeon, Head of Unit, Otolaryngology 2, The Alfred Hospital, Melbourne, Victoria

Antoinette David RN, GradCert(Neurosciences) Clinical Support and Development Nurse, Neurosurgery and Neurotrauma, The Alfred Hospital, Melbourne, Victoria

Andrew Davies MBBS, FRACP, FCICM Adjunct Clinical Associate Professor, Intensive Care Unit, The Alfred Hospital, Melbourne, Victoria Adjunct Associate Professor, Department of Epidemiology and Preventative Medicine, Monash University

Gavin A Davis MBBS, FRACS (Neurosurgery) Associate Professor, Neurosurgery, Department of Neurosurgery, Cabrini Hospital, Malvern, Victoria and Department of Neurosurgery, Austin Hospital, Heidelberg, Victoria

Bruce Day MBBS, FRACP Clinical Neurophysiologist, The Alfred Hospital, Melbourne, Victoria

Bianca Fedele BA(Hons) Research Assistant, Epworth Monash Rehabilitation Medicine Unit

Mark Fitzgerald MBBS, FACEM Adjunct Clinical Associate Professor, Director of Trauma Services, The Alfred Hospital, Melbourne, Victoria

Tony Goldschlager MBBS, DCH(London), PhD, FRACS Neurosurgical Registrar, The Alfred Hospital, Melbourne and Monash Medical Centre, Clayton Victoria

Russell L Gruen MBBS, PhD, FRACS Director, National Trauma Research Institute, Melbourne, Victoria Surgeon and Head of Trauma Quality Assurance, The Alfred Hospital, Melbourne, Victoria Professor of Surgery and Public Health, Monash University. Melbourne, Victoria

Mathew R Guilfoyle BSc, MBBCh, MRCS Academic Clinical Fellow, Addenbrooke ’ s Hospital, Cambridge, UK

Anthony Hall MD, FRANZCO Adjunct Clinical Associate Professor, Head of Unit, Department of Ophthalmology, The Alfred Hospital, Melbourne, Victoria

Peter Hutchinson BSc(Hons), MBBS, PhD, FRCS(Surg Neurol) Reader and Honorary Consultant Neurosurgeon, Addenbrooke ’ s Hospital, Cambridge, UK

Peter Hwang MBBS, FRACS, FRCS(Edin), FRCS(Glag), FCSS, FAMS Neurosurgeon, The Alfred Hospital, Melbourne, Victoria Adjunct Clinical Associate Professor, Central Clinical School, Monash University, The Alfred Hospital

Arvind Jain MBBS, MS(Ortho) Orthopaedic Principal Fellow, The Alfred Hospital, Melbourne, Victoria

Contributors and reviewers

xii CONTRIBUTORS AND REVIEWERS

Lucia M Li MA(Cantab), MBBChir Academic Foundation Doctor in Neurosurgery, Addenbrooke ’ s Hospital, Cambridge, UK

Susan M Liew MBBS(Hons), FRACS(Orth) Adjunct Clinical Associate Professor, Orthopaedic & Spine Surgeon, Director of Orthopaedic Surgery, The Alfred Hospital, Melbourne, Victoria Adjunct Clinical Associate Professor, Monash University, The Alfred Hospital, Melbourne, Victoria

Paul McCrory MBBD, PhD, FRACP, FACSP, FFSEM, FACSM, GradDipEpidStats Associate Professor, Centre for Health, Exercise and Sports Medicine & The Brain Research Institute, University of Melbourne, Victoria

Anoop Madan MBBS, FRANZCR Interventional Neuroradiologist, Department of Radiology, The Alfred Hospital, Melbourne, Victoria Adjunct Lecturer, Monash University, Melbourne, Victoria

Michael Makdissi BSc(Hon) MBBS PhD FACSP Research Fellow, Centre for Health, Exercise and Sports Medicine & the Brain Research Institute, University of Melbourne, Victoria

Biswadev Mitra MBBS(Melb), MHSM, MAAFP, FACEM Consultant Emergency Physician, The Alfred Hospital, Melbourne, Victoria

David Morgan MBBS, FRACS Plastic and Reconstruction Surgeon, The Alfred Hospital and Cabrini Brighton Medical Centre, Melbourne, Victoria

Alfredo Mori MBBS, Dip EBHC(Oxon), FACEM Emergency Physician, The Alfred Hospital, Melbourne, Victoria

John Olver MBBS, MD, FAFRM(RACP) Victor Smorgon Chair of Rehabilitation Medicine, Monash University, Melbourne, Victoria Director Rehabilitation, Epworth Healthcare, Melbourne, Victoria

Jeffrey V Rosenfeld AM MBBS(Melb), MD(Monash), MS(Melb), FRACS, FRCS(Edin), FACS, FRCS(Glasg)Hon, FCNST Hon, FRCST Hon, FACTM, MRACMA, RAAMC Professor and Head, Division of Clinical Sciences and Department of Surgery, Central Clinical School, Monash University, The Alfred Hospital, Melbourne,Victoria Director, Department of Neurosurgery, The Alfred Hospital, Melbourne, Victoria Major General and Surgeon General, Australian Defence Force — Reserves

Marc Seifman MBBS, BMedSc Surgical Registrar, The Alfred Hospital, Melbourne, Victoria

Jin W Tee MBBS, BMedSc Neurosurgery Registrar, The Alfred Hospital, Melbourne, Victoria Neurotrauma Research Fellow, The Alfred Hospital, Melbourne, Victoria

Alvin Teo MBBS, MMed, EDIC, FANZCA, FCICM, DDU Specialist in Intensive Care, The Alfred Hospital, Melbourne, Victoria

Simon Young MBBS(Hons), DipCrim, FACEM Director of Emergency Medicine, Royal Children ’ s Hospital, Parkville, Victoria

REVIEWERS Noel Eatough BSc(Med), MBBS, FACEM Staff Specialist, Royal North Shore Hospital, Sydney, and CareFlight, New South Wales

Michael Facek MBBS(Hons), BSc Orthopaedic Registrar, Mater Miscorderiae Hospital, New South Wales

Andrew Pearce BSc(Hons), BMBS, FACEM, PGCert Aeromed Ret Senior Staff Specialist, Emergency Medicine, Royal Adelaide Hospital, South Australia Associate Professor and Clinical Director, MedSTAR Emergency Medical Retrieval Service, South Australia Group Captain, RAAF Specialist Reserves; Clinical Director, Emergency Medicine and Aeromedical Evacuation

1

1 Epidemiology

Peter Bragge , Russell L Gruen

Every day, in every country, men, women and chil-dren sustain head injuries. Trips and falls, transport accidents, sporting injuries, interpersonal violence and military confl ict all lead to a spectrum of inju-ries to the face, scalp, skull vault, sense organs and, most importantly, to the brain itself.

Globally, at least 10 million people each year suffer a traumatic brain injury (TBI) that results in death or hospitalisation, and an estimated 57 million people worldwide have been hospitalised with one or more TBI. 1 Estimates of the annual incidence lie between 91 and 372 per 100,000, 2,3 and estimates of mortality range from 9 to 89 per 100,000. 4 Almost 60% of TBIs worldwide are due to road traffi c acci-dents, 20 – 30% to falls, 10% to violence and 10% to work or sports injuries 5 .

Epidemiology is the science that describes the occurrence of disease, risk factors, causal mecha-nisms and outcomes. Epidemiology provides prac-titioners and policy makers with valuable information about incidence (new cases), disease burden (includ-ing prevalence and outcomes such as death, dis-ability and cost), and the effect of prevention and treatment initiatives. At the level of a health service,

a state or a country, this information is essential for the planning and monitoring of injury prevention efforts, and treatment and disability services.

Of course every country has its own TBI epide-miology. Rather than being a comprehensive review of every country ’ s experience of TBI, however, this chapter focuses on the main global patterns of injury, how these patterns are changing and the implica-tions for the future.

DEFINITION, CLASSIFICATION, DATA

Epidemiology relies on reliable and valid data, and there are important challenges that relate to defi ni-tions, classifi cation and data availability.

TBI is usually defi ned as an injury to the brain resulting from an external force, leading to transient or permanent neurological dysfunction. 6 The most commonly used classifi cation for TBI consists of ‘ mild ’ , ‘ moderate ’ or ‘ severe ’ , based on duration of loss of consciousness and clinical presentation, the fi rst Glasgow Coma Score and the duration of post-traumatic amnesia, as shown in Table 1.1 .

TABLE 1.1 Classifi cation of TBI 6,7,8,9

Typical duration of LOC Clinical presentation

Typical fi rst GCS score

Typical duration of PTA

Mild TBI (concussion)

30 mins or less Awake; eyes open. Symptoms can include confusion, memory and attention diffi culties, headache, and behavioural problems.

14 – 15 Less than 24 hours

Moderate TBI More than 30 mins Lethargic; eyes open to stimulation; sleepy, but still arousable.

9 – 13 1 – 7 days

Severe TBI More than 30 mins Coma; eyes do not open, even with stimulation. 3 – 8 1 – 4 weeks

LOC = loss of consciousness; GCS = Glasgow Coma Scale; PTA = post-traumatic amnesia.

2 PRACTICAL TREATMENT OF HEAD AND NECK INJURY

of the distribution of pathological types of head injury among major trauma cases (injury severity score, ISS > 15) for the state of Victoria, Australia, where motor vehicle crashes, falls and interpersonal violence are the main causes of severe injury and fi rearm use is uncommon. Population-wide data is captured for all major trauma cases in the Victorian State Trauma Registry. In the 5 years from 2005 to 2009, there were 11,608 cases of major trauma in Victoria, and among these 6963 patients (60%) were coded as having a type of head injury. Of the major trauma patients with head injury, the most frequently coded ICD codes were concussion, subdural haem-orrhage, fractured base of skull, subarachnoid haemorrhage, diffuse brain injury and focal brain injury ( Table 1.2 ). Four per cent of patients who had moderate-to-severe head injury also had a cervical spine injury.

Other ways of classifying TBI, including clinical descriptions of the lesion and the presentation, vary with the nature, intensity, direction and duration of the external forces to the brain. 19 The four main patho-anatomical sequelae of TBI are contusion, subarachnoid haemorrhage, haematoma (including extradural, subdural and intraparenchymal lesions) and diffuse axonal injury (DAI). 17 Contusion arises from contact impact. Haematoma is present in 25 – 35% of patients with severe TBI and 5 – 10% of moderate TBI cases. DAI, which is characterised by multiple small lesions in white matter tracts, causes profound early coma and is associated with poor outcomes. 19 These sequelae are often found to co-exist in patients with severe and fatal TBI but can also do so in the setting of mild and moderate injuries. 17 Also important to the clinician is the presence of secondary insults, including ischaemia, hypoxia, cerebral oedema, hypotension, hypergly-caemia and hypercapnia / hypocapnia. 17,19,20

Irrespective of the classifi cation system used for coding TBI, there are factors limiting the availability and comparability of data within and between systems. These limitations include the following: • Most brain injuries (up to 80%) are mild (mTBI),

but data on mTBI are diffi cult to capture, as such injuries may receive no medical treatment, or may not be treated in hospitals where TBI data-bases are kept. 21,22

• TBI often occurs with multi-trauma and in mili-tary settings, and therefore is underreported or rolled into more general death and injury statistics. 21,22

The Glasgow Coma Scale (GCS) 10 is a clinical prognostic indicator commonly used for the initial assessment of severity of injury that requires the assessment of eye-opening, motor and verbal respon-siveness. While intended to be used as a repeated measure, it is often used as a single assessment and recorded as such in registry data.

Post-traumatic amnesia (PTA), a term fi rst used in 1928, refers to the period between the injury and the return of full, continuous memory, including any time during which the patient was unconscious. 11 PTA is a condition following a TBI that is charac-terised by confusion, disorientation, loss of memory post-injury and ‘ clouded ’ consciousness. 12,13 Conse-quently, patients in PTA may be unable to state their name and may be unaware of the time and where they are. 12 While a patient is in PTA, the ability to store new events in the memory is lost 14 ; therefore, a hallmark of PTA resolution is the return of con-tinuous memory. 15 In approximately one-third of PTA cases, a patient has ‘ islands of memory ’ and can recall some, but not all, events. 14 ‘ Retrograde amnesia ’ refers to failure to recall events prior to the injury, and ‘ anterograde amnesia ’ refers to failure to lay down new memories for a period following the injury.

Differences in classifi cation systems affect com-parability of data. 3 While the mild / moderate / severe distinction is useful for epidemiological purposes, there is ongoing debate about its validity for clas-sifi cation and prognostication. Diffi culties in using these categories, which can lead to inaccuracies, include the effects of sedation, intoxication, facial injury and intubation on GCS scores, the effect of the exact timing of measurement and the potential infl uence of shock and other organ system failure on the evaluation of GCS, consciousness and the dura-tion of PTA, and missing documentation of severity data in medical records. 16 Furthermore the poor cor-relation of GCS with the pathophysiological mecha-nisms underlying the neurological defi cits gives little direction to further management. 17

New means of assessment of global severity are emerging, including newer-generation imaging tech-niques such as diffusion tensor imaging (DTI), but, for the present, the mild / moderate / severe classifi ca-tion based on clinical features is likely to remain in widespread use. 17

Pathological classifi cation, the most widely used being the 10th edition of the International Classi-fi cation of Diseases (ICD-10), 18 complements func-tional severity scoring. We provide here an example

31 • Epidemiology

increase in high-income countries. Furthermore, by 2020 traffi c-related injuries will become the third-ranked cause of disability-adjusted life years (DALYs) lost (second-ranked cause of DALYs lost in low-to-middle income countries), with 71.2 million DALYs lost worldwide, representing 5.1% of the global burden of disease. 24

Motorcycle riders are at particular risk. For example, in the UK, motorcyclists comprise under 1% of road users but represent 14% of road deaths and serious injuries. They are killed or seriously injured at twice the rate of pedal cyclists and at more than 16 times the rate of car occupants. 25,26

Alcohol is a major contributing factor to traffi c-related head injury in many countries. For example, 64% of deaths and over a third of non-fatal injuries in child passengers in the USA have been linked to drink-driving. 27 Of course other causes of traffi c-related injury include speeding, sleepiness, failure to use safety harnesses, drugs that impair conscious-ness and driver response time, as well as character-istics that make the vehicles or roads usafe.

Of the remaining causes of TBI, falls produce 20 – 30% of TBIs worldwide, especially among young children and the elderly. The International Multicenter Study of Head Injury in Children, 28 con-ducted in fi ve countries, revealed the relative pro-portion of minor, moderate and severe TBI sustained was 56%, 39% and 5%, respectively, with a case fatality rate of 1.6. However, the burden of injury in children falls disproportionately upon poorer regions; the WHO estimates that over 95% of injury

• Injury reporting and surveillance systems vary across the world. 21 Hospital records, death cer-tifi cates, trauma registries and purpose-designed prospective observational studies provide the most reliable sources of data on occurrence and outcomes of TBI, but such data rarely capture all dimensions of brain injury.

There is a need for more accurate monitoring of the occurrence, severity and outcomes of TBI using standardised measures and processes of data collec-tion and reporting. National trauma registries are well suited to this purpose.

INCIDENCE AND MECHANISMS OF TBI

Throughout the world, TBI incidence by age is tri-modal, with peaks in early childhood, late adoles-cence and the elderly. 2 Data from the USA and Australia show that, overall, males are twice as likely as females to experience TBI. 22,23 This is pre-dominantly because of the adolescent male ’ s involvement in violence and traffi c-related injuries. At the extremes of age, males and females have a similar incidence of TBI. 2

Traffi c-related injuries account for 1.2 million deaths each year worldwide. The World Health Organization Global Burden of Disease Study fore-casts that by 2020 traffi c-related injuries will become the sixth-ranked major cause of death worldwide, representing 3.4% of all deaths worldwide. An 80% increase in traffi c-related deaths is forecast in low-income to middle-income countries and a 30%

Data provided with permission from the Victorian State Trauma Outcomes Registry (VSTORM).

TABLE 1.2 Distribution of International Classifi cation of Diseases 10th edition (ICD-10) codes of head injury in Victoria, Australia, 2005 – 09

ICD Code InjuryNumber of cases (1 Jan 2005 – 31 Dec 2009)

% major trauma cases

% cases with head injury

S060 Concussive injury 3899 33.6% 56.0%

S065 Traumatic subdural haemorrhage 2929 25.2% 42.1%

S021 Fractured base of skull 2027 17.5% 29.1%

S066 Traumatic subarachnoid haemorrhage 1888 16.3% 27.1%

S062 Diffuse brain injury 1725 14.9% 24.8%

S063 Focal brain injury 1534 13.2% 22.0%

S020 Fractured skull vault 987 8.5% 14.2%

S064 Extradural haemorrhage 798 6.9% 11.5%

S061 Cerebral oedema 432 3.7% 6.2%

S068 Other intracranial injuries 259 2.2% 3.7%

S069 Intracranial injury, unspecifi ed 62 0.5% 0.9%

4 PRACTICAL TREATMENT OF HEAD AND NECK INJURY

PTA duration is signifi cantly associated with attained educational level, cognitive function, anxiety and recovery, as measured by the Extended Glasgow Outcome Scale. 33

Moderate-to-severe TBI In the state of Victoria, the mortality rates in 2007 – 8 in the fi rst year after injury were 22.6% for moderate TBI and 35.1% for severe TBI. 23 US-based data indicates that mortality from TBI has decreased from 19.3 to 17.8 per 100,000 in the period 1997 – 2007, 34 continuing a downward trend established in earlier studies. 35,36

Most survivors of moderate-to-severe TBI face a range of long-term disabilities. For example, in a study of civilians in the USA, three years after severe head injury only 3 of 45 survivors did not suffer persisting and disabling symptoms. 37 Survi-vors face cognitive problems (for example, diffi cul-ties with concentration, memory and attention), psychological problems (depression and other mood disorders) and physical disabilities (spasticity, speech problems). Although physical disabilities are challenging, the neurobehavioural consequences of TBI have a comparatively greater impact on quality of life. 6 Cognitive and behavioural defi cits drive many of the lifestyle consequences of TBI, such as unemployment, relationship diffi culties and loss of independence. 6,38

The eventual outcome of TBI is determined by the initial pathology, management of the head injury and of the associated disability, and the presence of co-morbidities and concomitant injuries. Identifi ed predictors of TBI outcome include age, neurological status, trauma severity and CT characteristics. 31,39 Owing to the costs associated with providing optimal TBI care, it has also been demonstrated that the economic status of a region is signifi cantly associ-ated with the outcome of patients with severe TBI. 31

Burden of disease Costs of TBI can be divided into direct costs of medical and other care, and indirect costs — those relating to the loss, or partial loss, to society of the productive efforts (both paid and unpaid) of injury victims and their caregivers.

An economic analysis has estimated that each incident case of TBI in Australia presents an average lifetime cost of A$2.5 million for moderate TBI and A$4.8 million for severe TBI. 23 The total cost of moderate and severe TBI in Australia is estimated to be A$8.6 billion per year (A$3.7 billion for

deaths in children occur in low- and middle-income countries. 29

In the elderly, a fall may be the result of a trip or stumble, a cardiac or cerebrovascular event, or other co-morbidities, including the effects of psychoactive or cardiovascular drugs such as antihypertensives. Elucidating the actual cause of falls in the elderly can be diffi cult. Falls incidence also varies by country; the incidence of TBI due to falls in India is 43 per 100,000 compared to a worldwide falls-related TBI incidence of 13.3 per 100,000 1 ; India accounts for 50% of the known worldwide falls-related TBI. 21

Assault and violence contribute a further 10% of the world ’ s TBI cases. The incidence is dramatically higher in some populations. For example, while the worldwide incidence of TBI due to assault is 43 per 100,000, 1 in Johannesburg the incidence of fatal TBI in 2003 was 138 per 100,000 in males and 24 per 100,000 in females. 2 At a time when the incidence of assault-related TBI in the whole Australian popu-lation was 41 per 100,000, in Australian Indigenous communities it was 855 per 100,000, with Indi-genous females having a nearly 70 times higher rate than non-Indigenous females. 30 In Europe, the rate of assault-related TBI is signifi cantly higher in lower and upper-middle income countries than it is in high-income countries. 31

OUTCOMES AND THE OVERALL BURDEN OF TBI

Mild TBI Mild TBI patients make a full recovery in most cases. However, 10 – 15% of mTBI patients experi-ence ongoing problems, known as post-concussion syndrome (PCS). 6 This is characterised by a range of problems, including physical symptoms (e.g. headache, vestibular problems, fatigue and sleep disturbance), cognitive defi cits (problems with attention, memory, concentration) and behavioural changes (irritability, emotional lability). 6,7 These non-specifi c symptoms may present some time after mTBI, when patients attempt to return to previous activities, 7 making the diagnosis of PCS potentially challenging. The mechanisms of how mTBI leads to PCS remain uncertain, 32 and a range of factors other than those relating to injury severity, most notably psychological factors, are thought to play a role in PCS development. 32,33 A 10-year follow up study found that, among patients with mild head injury,

51 • Epidemiology

CHANGES IN TBI PATTERNS AND FUTURE IMPLICATIONS

In global terms, patterns of TBI are changing as a result of trends in motorisation, prevention and ageing. In high-income countries, road-traffi c related TBI has declined ( Fig 1.1 ). 35,43 Despite large numbers of motor vehicles, fewer transport-related injuries are occurring because of safer roads, safer cars, safer drivers and more timely and higher-quality emer-gency health services. 44 In Australia, much of the fall in the fatality rate since the late 1960s has been attributed to the introduction of seat belts, random breath testing and speed cameras. 45

However, the contribution of transport-related TBI mortality continues to rise in low- and middle-income countries ( Fig 1.2 ). While traffi c-related injuries are projected to be the third-highest cause of DALYs lost worldwide by 2020, they are fi fth in their contribution to the burden of disease in devel-oped regions and second in developing regions. 46 This disparity parallels the dramatic increase in motorisation without a similar increase of invest-ment in injury prevention in low-income and middle-income countries. In many countries, the growth in use of motorcycles, often without protec-tive helmets, has led to dramatic increases in the incidence of TBI. For example, in eastern China, traffi c-related incidence of TBI rose by 30% in 20 years, over 50% of which cases did not involve occupants of cars (20% pedestrians, 13% bicycles, 20% motorcycles). 47

moderate TBI and A$4.8 billion for severe TBI). The breakdown of these costs is given in Table 1.3 .

In 2002, TBI patients in the USA averaged an estimated US$65,600 in direct medical costs (US$4330 per day), US$1,003,140 in societal costs per deceased person, up to US$74,673 in societal costs for non-fatal injuries and US$1631 per day for rehabilitation services. 40 Economic modelling not only reveals important aspects of the burden of injury, but has also been used to demonstrate the cost savings of care improvements. Faul et al esti-mated that if every patient received care consistent with the Brain Trauma Foundation guidelines, 3,607 lives would be saved in the USA, and the savings in annual medical costs, annual rehabilitation costs and lifetime societal costs would be US$262 million, US$43 million and US$3.84 billion, respectively. 41

The burden of TBI in low-income and middle-income countries, therefore, has four important dimensions to it. First, there is a high preponderance of risk factors for TBI. Second, healthcare systems in low-income and middle-income countries are the least prepared to address TBI when it occurs. 21 Third, the increased percentage of poor outcomes from TBI relative to high-income countries further strains long-term or community services of these often poorly resourced health systems. It is esti-mated that 80% of the world ’ s disabled population live in low-income and middle-income countries, but only 2% can access rehabilitation. 42 Fourth, low-income countries are less equipped to implement strategies to abate TBI risk.

TABLE 1.3 Direct and indirect cost estimates for TBI in Australia 23

Category Defi nition / Examples

Cost (A$ millions)

Moderate TBI Severe TBI

Burden of disease Estimated dollar value of the loss of wellbeing due to TBI, using DALYs multiplied by the value given to a year of life (A$157,795 in Australia in 2008)

2206.6 2691.9

Lifetime lost earnings due to reduced employment

452.9 256.3

Long-term care Attendant care, integration teacher aide, accommodation or respite care, independent living unit, special accommodation and nursing-home supported community options

300.0 962.5

Healthcare costs Ambulance, hospital, medical, paramedical and administration 269.1 308.0

Administrative costs The costs of administering welfare pensions and raising additional taxation revenues

174.6 150.5

Aids and modifi cations Wheelchairs and gait aids, environmental modifi cations, hoists, home modifi cations

59.7 158.5

Lifetime carer costs Informal care: e.g. family and friends 25.1 28.5

6 PRACTICAL TREATMENT OF HEAD AND NECK INJURY

of the negative effect on outcomes of age itself and of age-associated comorbidities and medica-tions, such as anticoagulants.

Changes in demography and exposure to risk factors are changing the profi le of head injury in all countries. To properly plan for the future, clinicians, policy makers, and injury-prevention programs will need to take these trends into account. Because TBI can profoundly effect patients, their families and their communities, as well as the costs borne by governments, insurers, individuals and workplaces, prevention is the key. Clinicians have an important role in advocating safety initiatives to reduce the burden of TBI around the world.

SUMMARY

1. At least 10 million people each year suffer a TBI that results in death or hospitalisation.

2. Almost 60% of TBIs worldwide are due to road traffi c accidents, 20 – 30% to falls, 10% to vio-lence and 10% to work or sports injuries.

3. Several classifi cation systems exist, and mild TBI is grossly underreported.

Ageing of populations has also had an important effect on the incidence of TBI. In many high-income countries, for the fi rst time ever there are now more people over the age of 60 than children under the age of 15. One-fi fth of the population of high-income countries is already over 60 years of age, and it is estimated that by 2050 this age group will account for one-third of the population. The popula-tion of low-income and middle-income countries is also ageing, albeit more slowly.

As the older population has increased, the inci-dence of falls-related TBI has increased. In the USA, the number of road-traffi c crash and fi rearm-related TBI deaths has fallen over the period 1990 – 2007, but the number of falls-associated TBI deaths has risen. TBI death rates for the period 1997 – 2007 have fallen in persons aged 0 – 44, but increased in persons over 75 years of age. 34 Similarly, in Austra-lia hospitalised head injury in those aged over 60 years increased 1.4 times in the 5 years to 2004 – 05.

In addition to increased incidence of TBI, ageing of the population also affects the pattern of TBI through increased mortality and morbidity because

FIG 1.1 Road traffi c fatality trends in three high-income countries (Australia, UK, USA). (Reproduced from world report on road traffi c injury prevention. 24 )

71 • Epidemiology

FIG 1.2 Road traffi c fatalities, adjusted for underreporting, 1990 – 2020. (Reproduced from world report on road traffi c injury prevention. 24 )

4. Up to one-third of patients with moderate-to-severe TBI die, and most survivors suffer long-term cognitive, psychological and physical disabilities. The cost of TBI in Australia is esti-mated to be A$8.6 billion per year in burden of disease, lost productivity, healthcare and disabil-ity costs, with each case costing A$2.5 – 4.8 million in a lifetime.

5. The epidemiology of TBI is changing. In high-income countries, the incidence of severe TBI associated with road-traffi c crashes is declining, but the incidence of falls-related TBI in the elderly is increasing. In many low- and middle-income countries the incidence of traffi c-crash-related TBI is rapidly increasing.

REFERENCES 1. Murray C , Lopez A . Global health statistics . Geneva :

World Health Organization ; 1996 .

2. Bruns Jr J , Hauser WA . The epidemiology of traumatic brain injury: a review . Epilepsia . 2003 ; 44 ( Suppl 10 ): 2 - 10 .

3. Fortune N , Wen X . The defi nition, incidence and prevalence of acquired brain injury in Australia . Canberra : Australian Institute of Health and Welfare ; 1999 .

4. Fearnside M , Simpson D . Epidemiology . In: Reilly P , Bullock R , eds. Head injury: pathophysiology and management . 2nd ed . London : Hodder Arnold ; 2005 : 3 - 25 .

5. Gururaj G . An epidemiological approach to prevention, prehospital care and rehabilitation in neurotrauma . Neurology India . 1995 ; 43 ( 3 ): 95 - 106 .

6. Khan F , Baguley IJ , Cameron ID . 4: Rehabilitation after traumatic brain injury . MJA . 2003 ; 178 ( 6 ): 290 - 295 .

7. Kay T , Harrington D , Adams R . Defi nition of mild traumatic brain injury . J Head Trauma Rehabil . 1993 ; 8 ( 3 ): 86 - 87 .

8. Brain Trauma Foundation . TBI Glossary . Online. Available at : < https://http://www.braintrauma.org/tbi-glossary/ > ; accessed 3 June 2011 .

8 PRACTICAL TREATMENT OF HEAD AND NECK INJURY

26. Department of Environment TatR . Tomorrow ’ s roads — safer for everyone: the Government ’ s road safety strategy and casualty reduction targets for 2010 . London : Department of Environment, Transport and the Regions (DETR) ; 2000 .

27. Quinlan KP , Brewer RD , Sleet DA , et al . Characteristics of child passenger deaths and injuries involving drinking drivers . JAMA . 2000 ; 283 ( 17 ): 2249 - 2252 .

28. Murgio A , Andrade FA , Sanchez Munoz MA , et al . International multicenter study of head injury in children. ISHIP Group . Childs Nerv Syst . 1999 ; 15 ( 6-7 ): 318 - 321 .

29. Peden M , Oyegbite K , Ozanne-Smith J , et al . World report on child injury prevention . Geneva : World Health Organization ; 2008 .

30. Jamieson LM , Harrison JE , Berry JG . Hospitalisation for head injury due to assault among Indigenous and non-Indigenous Australians, July 1999 – June 2005 . Med J Aust . 2008 ; 188 ( 10 ): 576 - 579 .

31. Mauritz W , Wilbacher I , Majdan M , et al . Epidemiology, treatment and outcome of patients after severe traumatic brain injury in European regions with different economic status . Eur J Public Health . 2008 ; 18 ( 6 ): 575 - 580 .

32. Williams WH , Potter S , Ryland H . Mild traumatic brain injury and postconcussion syndrome: a neuropsychological perspective . J Neurol Neurosurg Psychiatry . 2010 ; 81 ( 10 ): 1116 - 1122 .

33. Ponsford J , Willmott C , Rothwell A , et al . Factors infl uencing outcome following mild traumatic brain injury in adults . J Int Neuropsychol Soc . 2000 ; 6 ( 5 ): 568 - 579 .

34. Coronado V , Xu L , Basavaraju S , et al . Surveillance for traumatic brain injury – related deaths — United States, 1997 – 2007 . Atlanta, GA : Centers for Disease Control and Prevention ; 2011 .

35. Lu J , Marmarou A , Choi S , et al . Mortality from traumatic brain injury . Acta Neurochir Suppl . 2005 ; 95 : 281 - 285 .

36. Zink BJ . Traumatic brain injury outcome: concepts for emergency care . Ann Emerg Med . 2001 ; 37 ( 3 ): 318 - 332 .

37. Zaloshnja E , Miller T , Langlois JA , et al . Prevalence of long-term disability from traumatic brain injury in the civilian population of the United States, 2005 . J Head Trauma Rehabil . 2008 ; 23 ( 6 ): 394 - 400 .

38. Rimel RW , Giordani B , Barth JT , et al . Moderate head injury: completing the clinical spectrum of brain trauma . Neurosurgery . 1982 ; 11 ( 3 ): 344 - 351 .

39. Murray GD , Butcher I , McHugh GS , et al . Multivariable prognostic analysis in traumatic brain injury: results from the IMPACT study . J Neurotrauma . 2007 ; 24 ( 2 ): 329 - 337 .

40. Finkelstein E , Corso P , Miller T . The incidence and economic burden of injuries in the United States . New York : Oxford University Press ; 2006 .

41. Faul M , Wald M , Rutland-Brown W , et al . Using a cost – benefi t analysis to estimate outcomes of a clinical treatment guideline: testing the Brain Trauma

9. Rosenthal M , Griffi th E , Bond M . Rehabilitation of the adult and child with traumatic brain injury . 2nd ed . Philadelphia : FA Davis ; 1990 .

10. Teasdale G , Jennett B . Assessment of coma and impaired consciousness. A practical scale . Lancet . 1974 ; 2 ( 7872 ): 81 - 84 .

11. McCaffrey R . Special issues in the evaluation of mild traumatic brain injury. The practice of forensic neuropsychology: meeting challenges in the courtroom . New York : Plenum Press ; 1997 : 71-75 .

12. Lee LK . Controversies in the sequelae of pediatric mild traumatic brain injury . Pediatr Emerg Care . 2007 ; 23 ( 8 ): 580 - 583 ; quiz 4-6 .

13. Trzepacz P , Kennedy R . Delerium and posttraumatic amnesia . In: Silver J , McAllister T , Yudofsky S , eds. Textbook of traumatic brain injury . Arlington : American Psychiatric Pub. ; 2005 : 175 - 176 .

14. van der Naalt J . Prediction of outcome in mild to moderate head injury: a review . J Clin Exp Neuropsychol . 2001 ; 23 ( 6 ): 837 - 851 .

15. Petchprapai N , Winkelman C . Mild traumatic brain injury: determinants and subsequent quality of life. A review of the literature . J Neurosci Nurs . 2007 ; 39 ( 5 ): 260 - 272 .

16. Malec JF , Brown AW , Leibson CL , et al . The Mayo classifi cation system for traumatic brain injury severity . J Neurotrauma . 2007 ; 24 ( 9 ): 417 - 424 .

17. Saatman KE , Duhaime AC , Bullock R , et al . Classifi cation of traumatic brain injury for targeted therapies . J Neurotrauma . 2008 ; 25 ( 7 ): 719 - 738 .

18. World Health Organization . International statistical classifi cation of diseases and related health problems: 10th revision , 2007 . Online. Available at : < http://apps.who.int/classifi cations/apps/icd/icd10online/ > ; accessed 23 June 2011 .

19. Maas AI , Stocchetti N , Bullock R . Moderate and severe traumatic brain injury in adults . Lancet Neurol . 2008 ; 7 ( 8 ): 728 - 741 .

20. Moppett IK . Traumatic brain injury: assessment, resuscitation and early management . Br J Anaesth . 2007 ; 99 ( 1 ): 18 - 31 .

21. Hyder AA , Wunderlich CA , Puvanachandra P , et al . The impact of traumatic brain injuries: a global perspective . NeuroRehabilitation . 2007 ; 22 ( 5 ): 341 - 353 .

22. Langlois JA , Rutland-Brown W , Wald MM . The epidemiology and impact of traumatic brain injury: a brief overview . J Head Trauma Rehabil . 2006 ; 21 ( 5 ): 375 - 378 .

23. Access Economics. The economic cost of spinal cord injury and traumatic brain injury in Australia. Report by Access Economics Pty Limited for The Victorian Neurotrauma Initiative, June 2009.

24. World Health Organization . World report on road traffi c injury prevention . Geneva : World Health Organization ; 2004 .

25. Clarke D , Ward P , Bartle C , et al . In-depth study of motorcycle accidents . London : Department for Transport ; 2004 .

91 • Epidemiology

45. Department of Infrastructure and Transport . Effectiveness of measures to reduce road fatality rates . Canberra : Department of Infrastructure and Transport — Bureau of Infrastructure, Transport and Regional Economics ; 2010 .

46. Murray CJ , Lopez AD . Alternative projections of mortality and disability by cause 1990 – 2020: Global Burden of Disease Study . Lancet . 1997 ; 349 ( 9064 ): 1498 - 1504 .

47. Wu X , Hu J , Zhuo L , et al . Epidemiology of traumatic brain injury in eastern China, 2004: a prospective large case study . J Trauma . 2008 ; 64 ( 5 ): 1313 - 1319 .

Foundation guidelines for the treatment of severe traumatic brain injury . J Trauma . 2007 ; 63 ( 6 ): 1271 - 1278 .

42. Jamison D , Bremen J , Measham A , et al . Disease control priorities in developing countries . 2nd ed . Washington : Oxford University Press ; 2006 .

43. Sosin DM , Sacks JJ , Smith SM . Head injury-associated deaths in the United States from 1979 to 1986 . JAMA . 1989 ; 262 ( 16 ): 2251 - 2255 .

44. Klauber MR , Marshall LF , Toole BM , et al . Cause of decline in head-injury mortality rate in San Diego County, California . J Neurosurg 1985 ; 62 ( 4 ): 528 - 531 .