CTG MADE EASY Evolve Learning Resources for Students and Lecturers. Access to the website: http://evolve.elsevier.com/Gauge/CTG/ For Elsevier: Commissioning Editor: Mairi McCubbin Development Editor: Helen Leng Project Manager: Sukanthi Sukumar Designer: Charles Gray Illustration Manager: Bruce Hogarth CTG MADE EASY F O U R T H E D I T I O N Susan M Gauge BSc(Hons) SRN SCM ADM ONC Clinical Education Midwife, Delivery Suite, Birmingham Women’s Healthcare NHS Trust, Birmingham, UK With a contribution by Andrew Symon MA(Hons) PhD RGN RM Senior Lecturer, School of Nursing and Midwifery, University of Dundee, Dundee, UK Foreword by Tracey A Johnston MD FRCOG Consultant in Maternal and Fetal Medicine, Birmingham Women’s Hospital, Birmingham, UK Edinburgh • London • New York • Oxford • Philadelphia • St Louis • Sydney • Toronto 2012 © 2012 Elsevier Ltd. All rights reserved. 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First edition 1992 Second edition 1999 Third edition 2005 Fourth edition 2012 ISBN: 978-0-7020-4349-9 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data A catalog record for this book is available from the Library of Congress Notices Knowledge and best practice in this fi eld are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. 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The Publisher’s policy is to use paper manufactured from sustainable forests Printed in China Contents Foreword v ii The CTG in litigation 2 9 Preface ix Conclusion 3 3 Acknowledgements x References 34 Part 1 Assessing fetal well-being Part 4 Case studies 3 5 in labour 1 Section 1: Normal 3 7 Introduction 2 Section 2: Bradycardia 4 9 Intermittent auscultation 3 Section 3: Tachycardia 5 7 Continuous electronic fetal heart rate Section 4: Reduced variability 6 7 monitoring 4 Section 5: Early decelerations 8 3 Adjuncts to CEFM for fetal surveillance 6 Section 6: Late decelerations 9 1 Conclusion 8 Section 7: Variable decelerations 9 7 References 8 Section 8: Prolonged decelerations 1 11 Section 9: Complex 1 15 Section 10: Miscellaneous 1 29 Part 2 Interpretation of the CTG 1 1 Control of the fetal heart rate 1 2 Part 5 Good practice guide 157 Interpretation of the CTG 1 3 Features of the cardiotocograph 1 4 Introduction 1 58 Basic patterns 1 4 Developing guidelines 1 58 Periodic changes 1 7 Audit 1 58 Interpretation of the data 2 2 Communication 1 58 Management of a suspicious CTG 2 3 Training and development 1 58 Management of a pathological CTG 2 3 Supervisors of midwives 1 59 References 24 Practical guides 1 59 Risk assessment chart 1 59 Web addresses 161 Part 3 Litigation and the CTG 2 7 References 161 Andrew Symon Introduction 2 8 Index 163 Background to CTG litigation 2 8 Online Contents CASE STUDIES Section 1 Normal Section 2 Bradycardia Section 3 Tachycardia Section 4 Reduced variability Section 5 Early decelerations Section 6 Variable decelerations Section 7 Complex Section 8 Miscellaneous Foreword All of us involved in delivering intrapartum care have taking place in the fetal circulatory system. The section an obligation to the women and babies in our care, as on intermittent auscultation is particularly welcome, as well as to the institutions we work for and to ourselves, some midwives feel they have lost their skills secondary to be fully competent and confi dent in all aspects of to the reliance on electronic fetal monitoring that has intrapartum fetal monitoring. This is a basic requirement predominated intrapartum care until recently, and many as an understanding of the mechanisms of labour. As doctors have never learned the skill. This text gives a clear, Part 3 of this book highlights, errors in all aspects of evidence-based approach to all aspects of intrapartum fetal fetal monitoring still occur, sometimes with profound monitoring which is easy to read and understand. Part 4 then consequences for the child and his/her family. Teaching allows readers to put what they have learned into practice and training are now more robust, and indeed form part with the wide range of cases and scenarios. No matter of annual mandatory training, but fetal monitoring is still what level of expertise exists, whether learning the skill of an area that causes many junior midwives and doctors intrapartum fetal monitoring for the fi rst time or refreshing some degree of anxiety. Most practitioners will consult existing knowledge, this text will benefi t all practitioners, and a text to refresh and improve their knowledge, and this in turn, the women and children we care for. book does exactly what it says on the cover – makes CTG interpretation easy! A basic knowledge of the physiology of fetal heart rate Tracey A Johnston MD FRCOG control is essential. It aids understanding of the changes Consultant in Maternal and Fetal Medicine seen in fetal monitoring and contextualises the changes Birmingham Women’s Hospital This page intentionally left blank Preface Fetal heart rate monitoring during labour has become For those not familiar with the origin of the book, the an accepted means of assessing the well-being of a baby. idea of a case-study approach to aid the interpretation However, in order for the resulting data to be of value it of CTGs arose in 1986 as a result of the Teaching and is vital that midwives, obstetricians and students have a Assessing in Clinical Practice course for midwives. A knowledge of the methods of fetal heart rate monitoring teaching package was produced containing a number of available, the physiology of fetal heart rate abnormalities, case histories, including a section on the CTG, followed the recommended terminology that should be used by an analysis and description of the management when interpreting data ( National Collaborating Centre instituted at the time. The package was used extensively for Women’s and Children’s Health 2007 ) and the in a number of delivery suites by midwives and doctors, appropriate management of such abnormalities. initiating lively discussion. We know, from the comments It is important that women have a choice in the of many doctors and midwives in the UK, that CTG Made method of fetal heart rate monitoring during labour. Easy is used widely, arouses debate and aids learning. Professionals must be able to give an explanation, based The book has an international readership and has been on available evidence, as to the risks and benefi ts of both translated into German, Chinese and French. intermittent auscultation and continuous electronic fetal In this, the fourth edition, we continue to follow the heart rate monitoring, and these discussions are included previous format, but with a number of revisions and in this text. additions. Part 1 includes wider discussions and reference Developments in fetal heart rate monitoring are to published evidence regarding available methods of ongoing, particularly regarding the use of decision fetal monitoring, with more information relating to support software packages ( Barber et al. 2010 ; Jameen intermittent auscultation. Assessing risk in labour is et al. 2010 ). Whilst we aim to provide women with as discussed as well as more recent developments in fetal normal experience as possible, electronic fetal heart rate monitoring practice. monitoring is recommended for high-risk women in Part 2 has been expanded to include more information labour and the technology is becoming more complicated regarding the physiological control of fetal heart and, in some instances, more invasive. Professionals rate and CTG abnormalities. Reference is made to involved in the care of women in labour should be aware national recommendations for the categorisation of of these developments and the effects they may have on CTGs ( National Collaborating Centre for Women’s intrapartum care. and Children’s Health 2007 ) and a proforma to aid The information within this book will hopefully consistency in interpretation ( Draycott et al. 2008 ). inform practitioners and motivate them to seek out Part 3, Litigation and the CTG, with its use of legal case results of ongoing and future research for the benefi t of studies to illustrate important lessons, has been updated women within their care. and gives an insight into the role of the CTG when A number of texts are already in existence which allegations of clinical negligence are investigated. describe in detail fetal physiology and monitoring The case studies section, Part 4, has been reviewed. techniques. It is not intended to cover the same The CTGs have been interpreted in line with ground in this book, but to complement them by recommendations from the National Institute for Health providing a basic grounding in the physiology of and Clinical Excellence ( National Collaborating Centre fetal heart rate monitoring, the main focus being the for Women’s and Children’s Health 2007 ) and new CTGs initiation of discussions relating to the interpretation have been added. Questions concerning the CTG are of cardiotocographs (CTGs). It is hoped that this will raised for consideration by the reader or group, with the be achieved by providing a series of examples of CTGs opportunity to make notes. In addition, 20 new cases are produced during labour. available online to complement the book. This book is aimed at all midwives, midwifery students, Part 5 introduces a number of ways to develop good- obstetricians and medical students and anyone with practice initiatives that can be adapted to suit the needs an interest in fetal heart rate monitoring. It is hoped of any trust. that it will go some way towards increasing knowledge, Your comments on any aspect of the book are confi dence and competence and thereby maintaining welcome, particularly if you have any useful guides to safety for the women and babies we care for. good practice that could be included in future editions.