What you should know after a year of anaesthesia training

300 Pages·2016·8.8 MB·English

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Acknowledgements

Thanks to all the registrars and junior doctors who have worked in my Department over the
years for the opportunity they have given me to both teach and learn from them.
Thanks to all those people who have said over the years, “You should write a textbook.” Now I
can say that I have done so.
Thanks to my colleagues for their comments and insightful feedback.
Thanks to Barb Lindbergs for permission to use the Anaesthetic Machine check documents and
for access to her costing spreadsheets.

Lastly I would like to thank my wife who inspires and tolerates me.

I welcome any comments, criticism or vitriol and they can be conveyed to me at
[email protected]

Lachlan Rathie
Toowoomba
April 2016

Disclaimer

Every effort has been made to ensure the information contained within this book is accurate
and correct; especially with regard to drug dosages. Despite this, errors may have been made
and advances or changes in medical science and practice may render some information
incorrect or incomplete. Current drug product information monographs are the most reliable
source of prescribing information.

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TABLE OF CONTENTS

Setting the scene

A bit about the structure of this book ....................................................................... 7
Why have I written this book? .................................................................................... 9
Common errors made by trainee anaesthetists ....................................................... 12
Curriculums.................................................................................................................. 13
What you should be able to do after a year ............................................................. 15
Resources ..................................................................................................................... 17
How to learn anaesthesia ........................................................................................... 21
Tools of the Trade
Monitoring- all those pretty waveforms .................................................................. 25
The Electroencephalogram and Its Application to Anaesthesia .......................... 32
The Anaesthetic Machine .......................................................................................... 45
The White Stuff ........................................................................................................... 53
Thiopentone and Ketamine ...................................................................................... 63
Volatile Agents and Nitrous Oxide .......................................................................... 68
Muscle Relaxants and Reversal ................................................................................. 84
Analgesics, Antiemetics and Local Anaesthetics .................................................... 98
The Main Event
Preoperative Assessment ......................................................................................... 108
Planning the Anaesthetic ......................................................................................... 127
The IV and drawing up drugs ................................................................................. 132
Induction of Anaesthesia ......................................................................................... 138
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Maintenance of Anaesthesia .................................................................................... 144
Emergence ................................................................................................................. 151
How to do a spinal (& an epidural) ........................................................................ 156
Everything you should know about Propofol TCI .............................................. 168
Putting it all together- Example Cases ................................................................... 177
Special Situations
Obstetric Anaesthesia ............................................................................................... 185
Paediatric Anaesthesia .............................................................................................. 201
The Obese Patient .................................................................................................... 209
A few words about endoscopy................................................................................ 218
Crises in a Nutshell
Difficult Airway 101 ................................................................................................. 222
Hypoxia ...................................................................................................................... 236
Hypotension .............................................................................................................. 240
High Airway Pressure ............................................................................................... 243
Perioperative Medicine
Studies you should probably know about ............................................................. 248
Antithrombotic Drug Management ....................................................................... 253
The bleeding patient and transfusion therapy ...................................................... 257
Making a Difference ................................................................................................. 268
Miscellany
My Top Twenty Tips ................................................................................................ 276
The Cost of Things ................................................................................................... 277
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Preparing for the Primary Examination ................................................................ 279
Pre-Questionnaire ..................................................................................................... 283
Initial Assessment of Anaesthetic Competence- example paper ....................... 285
Midyear Checklist for Meeting with Supervisor- JCCA ...................................... 288
My Other Books ....................................................................................................... 290

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Setting the scene

An assortment of textbooks from the author's personal collection

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A bit about the structure of this book

This book is arranged into seven sections. The first section endeavours to explain why I have
written this book. It outlines the existing deficits in the textbook literature, the shortcomings
in trainee knowledge I have witnessed firsthand and the errors that have resulted. The two
curriculums pertaining to anaesthetic training in Australia are briefly described as well as their
practical implications. I have listed what skills and attributes that are both likely and necessary
to be gained after a year of anaesthetic practice. The best available resources are reviewed to
inform practitioners of their value to the learner anaesthetist and perhaps help you decide
whether to buy any of them for your personal library. Finally are some thoughts about how
to learn anaesthesia.

The second section, ‘Tools of the Trade’, gives some detailed core information about the
integral tools of our profession- namely our equipment with a focus on the anaesthetic
machine and patient monitors and the drugs with a focus on the important anaesthetic drug
classes. A common theme in the book is to expressly focus on pragmatic but core knowledge
that is required to conduct anaesthesia safely but is lacking or hard to find in conventional
learning resources. At the end of some of the chapters in this section and the next four are
up to three separate items. The first of these are selected references. These are not exhaustive
or definitive but references I feel worthy of reading in their own right by the junior
anaesthetist. The second item comprises challenge questions relating to the content in the
preceding chapter or chapters. The answers are on the following page. Some of these will
even challenge your consultant! The third component that follows some chapters I
collectively term ‘light relief’ and contains items of a humorous/ cynical/ sarcastic nature.

The third and largest section of this book I have dubbed ‘The Main Event’. This relates to
the actual conduct of anaesthesia and is further subdivided into chapters relating to
preoperative assessment, planning and giving the anaesthetic. There is a detailed chapter
about propofol TCI, a subject whose practical application is a lot better realized than an
understanding of its theoretical foundation. Lastly is a section outlining in a stepwise fashion
the anaesthetic management of some common cases. To an extent this synthesizes
information from earlier chapters and applies it to example cases. The emphasis is very much
on giving a practical and common sense foundation to what we do every day in the operating
theatre. I believe you should critically appraise and be able to justify your practice and this
section attempts to do just that.

The next section relates to the two main specialty areas of anaesthetics that all generalist
anaesthetists practise in- namely obstetrics and paediatrics. Again common errors and deficits
are addressed as well as practical considerations for safe practice. A chapter is devoted to the
most significant challenge of our professional lives- obesity. Finally are some thoughts about
the commonest procedures performed that require anaesthetic services, namely endoscopy.

The fifth section relates to crisis management. There are many good resources on this subject
(including one I wrote) so I have restricted this section to the three commonest crises
encountered intraoperatively: hypoxia, hypotension and high airway pressures. Airway crises
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feature prominently in the anaesthesia canon so the section commences with a discussion
regarding difficult airway management.

The next section relates to aspects of perioperative medicine. This is a very large component
of contemporary anaesthetic practice and I have restricted myself to the more common issues
that anaesthetists have to deal with on a daily basis. This is an element of practice which is
informed to a degree by an evidence base. Consequently I have tried to highlight the
important studies of relevance as well as making the trainee anaesthetist aware of the multiple
situations where there is a lack of quality evidence to inform practice. My personal
perspective on how we as anaesthetists can make a difference to important perioperative
outcomes is succinctly outlined.

Finally, in the aptly titled ‘Miscellany’ section is an assortment of topics. A list of the cost of
commonly used anaesthetic drugs and consumables is included for your consideration. Cost
efficiency is an important attribute of the contemporary anaesthetist. Most anaesthetists in
their first year are contemplating if not studying for the primary exam so my personal
thoughts about how to tackle this life defining event are included for your consideration. An
example of the IAAC (Initial Assessment of Anaesthetic Competence) exam I give my
trainees is reproduced. This serves as an indicator of the level of knowledge you should
possess after approximately six months on the job. Lastly, if you enjoy my ‘light relief’ items
there’s a blurb about my two ‘other’ books most of the items came from: The Anaesthetist’s
Companion and The Cynical Anaesthetist.

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Why have I written this book?

My predominant anaesthetic interest pertains to educating the next generation of anaesthetists.
My credentials that demonstrate this are my role as the Supervisor of Training (SOT) of
anaesthetic trainees in a large regional hospital. I am also a primary examiner for the College of
Anaesthetists. Prior to becoming an anaesthetist I was a rural general practitioner (GP) in
South Western Queensland and completed a Fellowship with the College of General
Practitioners as well as a Graduate Diploma in Rural General Practice and a Diploma in
Obstetrics and Gynaecology. My first real exposure to anaesthesia was my advanced skills year
of anaesthetics that I did as a component of my rural GP training. I essentially decided to
pursue anaesthesia as a career because I enjoyed giving anaesthetics more than consulting. I
also like the academic and professional challenges that the specialty provides. I became an
examiner because it appeals to the academic snob in me and because I consider it the defining
element of our training and it reflects the high level of training that Australasian anaesthetists
receive. I am inherently biased but I think Australasian anaesthetists are the best in the world
and I want to contribute to maintaining that proud record.

I am a bit of a textbook junkie and have accrued quite a large collection over the years. The vast
majority of texts are an expensive disappointment. Common themes of disappointment are
outlined below:
 Overt American or UK flavour
 Out of date
 Can’t find ‘exam’ answer
 Inadequate explanation of fundamental concepts
 Unreadable, boring, dry
 Nothing ‘new’
 Patchy coverage of topics
 No practically useful information
The last disappointment detailed above is the biggest crime- the answers to practical questions
regarding how to anaesthetize the patient I have in front of me are invariably not found in
books. Try and find in a textbook the answer to the following questions:
 What are the criteria for extubation?
 What is the intubating dose of rocuronium in a patient who weighs 150kg?
 How do I interpret a post tetanic count?
 How long does the patient have to be off Rivaroxaban/ Dabigatran/ Prasugrel before I
can do a spinal?
 Do platelets/ FFP need to be ABO compatible?
 How do I manage a LMA with a leak?
 What’s the point of giving Midazolam on induction?
 Should I use a cuffed tube in a 4 year old?
 When do I cancel a kid with an URTI?
 How do I intubate someone without muscle relaxants?
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