DAS eZINE September 2022

DIFFICULT AIRWAY SOCIETY MEMBERS EZINE September 2022 Edition

Dif cult Airway Society E-Zine

September 2022

REMINDER TO DAS MEMBERS Please remember to update your details if your address or email address changes!

Members can update their details by emailing das@anaesthetists.org

WE WANT TO HEAR FROM YOU DAS encourages member participation – we would love to read your comments, contributions and suggestions for future E-Zines. Have you been involved in an interesting airway case? Is there an article that has changed your practice? Do you have an idea for improving airway anaesthesia that you would like to collaborate on?

All formats welcome: text, video, photo, infographic… We know you are a creative bunch! Send us your thoughts at ezine@das.uk.com.

@dasairway @dastrainees

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Dif cult Airway Society E-zine

May 2022

CONTENTS Miscellaneous

Executive Updates Editorial

4

Letters to the editors

6

DAS Executive Update

7

DAS Scienti c Of cer Report

9

DAS 2022

13

In Memory Of Dr Ronnie Cormack

Airway Management in Major Trauma - an Australian Perspective

54

New patient information for awake tracheal intubation: June 2022

59

Dif cult Airway Database - an update

61

Conference Corner 11

WAMM

63

Proposals to host DAS 2024

64

Education Clinical Dilemma

14

Educational Series: Perioperative Medicine Part 2 22 #JanuAIRWAY - The Compilation

41

Masterclass with DAS: Abstracts

43

Trainees Trainee Competition Winners

46

Journal Club - Recommended Reads

52

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EDITORIAL | Helen Aoife Iliff | Natalie Silvey | Moon-Moon Majumdar |

Welcome to the September 2022 edition of

equivalently experienced locally-employed

the Dif cult Airway Society E-Zine.

doctor.

We would like to start by expressing our

This month’s clinical dilemma pays due

sadness to hear of the death of Dr Ronnie

respect to ‘the compromised airway’ and

Cormack. There is no anaesthetist in the UK

covers a range of dire circumstances (what if

(or in fact, globally) who hasn’t used the

they’re hypoxic? What if they’re agitated?

Cormack and Lehane classi cation: a team-

What if they’re six?). Our airway experts have

understanding of your view is a crucial part of

risen to the challenge, and we hope you nd

safety in airway management. We have a

their thought processes as useful as we do.

very

tting tribute to Dr Cormack from Dr

Ellen O’Sullivan (Past President of DAS) and Dr Adrian Pearce (Founding Member of DAS).

Ms Kate Rivett, DAS patient representative, writes an important article about the need for high quality written information for our patients during the process of consent. She

We have the second of our three-part

reveals the new DAS awake tracheal

educational series focusing on peri-operative

intubation patient information lea et, easily

medicine, this time with exceptional authors

available on the DAS website for you to print

covering Frailty, Cardio-Pulmonary Exercise

for your own patients.

Testing, and Risk Assessment*. We are lucky to have the team from the Alfred Hospital in Melbourne writing an exciting article about traumatic airway management and their fantastic trauma service.

It is obvious that anaesthetic trainees are an incredibly creative bunch, and we had a wealth of submissions for this year’s Dif cult Airway Society trainee competition. For the rst time in 2022, we had two categories to

We continue the trend of popular educational

enter: creative writing and creative media. We

webinars run by the inimitable Dr Gunjeet

are ecstatic to award the

Dua. Most recently this was ‘A Masterclass

creative writing to Dr Asya Veloso Costa, and

with DAS: Abstracts’: a must watch to get

the rst prize for creative media to Dr Helena

your CV up to scratch as a trainee or an

Jennison. In fact, the standard of

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rst prize for

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submissions was so high the judges ended up

opportunity to catch up with colleagues in

awarding 3 extra prizes for:

person after a long time apart.

1. Best podcast - Dr Eoin Dore and Dr

If you have any feedback or ar ticle

Duncan Brouwer-Kemp

contributions please get in touch with our editorial team by emailing ezine@das.uk.com

2. Best video - Dr Jo Lau

o r t a g u s o n Tw i t t e r @ d a s a i r w a y o r

3. Best photography - Dr Hannah Leaman

@dastrainees.

We cannot wait to showcase all their amazing

Moon-Moon Majumdar

work to you in this edition.

Natalie Silvey

Finally, it’s the DAS 2022 ASM from the 5-7th October. Book your leave, get your trains/

Helen Iliff

ights sorted … because this year we are

*If you missed the rst in the peri-op series,

going to Newcastle! Get ready for some

don’t be shy! You can nd the May 2022 E-

insightful learning, and a wonderful

zine here, go back and have a peruse. You’re welcome

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September 2022

LETTERS TO THE EDITORS | Please get in touch, we love hearing from you! |

To: trainee@das.uk.com From: Professor André van Zunder, Professor and Chairman Discipline of Anesthesiology, The University of Queensland.

Subject: DAS E-Zine - May 2022 Thank you for sending the May edition of the Dif cult Airway Society E-Zine.

I appreciate this very much. It is easy to download and the content is worth reading and helps to better understand airway problems. Congratulations to the whole team.

DAS has an important place in the lives of anaesthetists as they all have to take care in airway management, the prime source for things going astray. All anaesthetists faced with fatal complications in airway management have still sleepless nights years after such an event. It is therefore of utmost importance to train the skills of airway management in all its aspect to help the anaesthetist to do a good job if confronted with a major dif cult to prevent mishaps from happening. Furthermore, DAS has other issues to offer, such as monitoring of the airway during induction, maintenance and emergence of the anaesthetic.

Short written information in the DAS E-zine are well-appreciated as they give us tips and tricks to improve our practice in the interest of better patient care.

Editors Response: Thank you for your kind feedback it is much appreciated. We've put a lot of work into the formatting and content of the eZine to try and make it as easily accessible to members as possible while simultaneously curating content. We're delighted to hear our members nd it easy to access and the content of interest.

Editors Note: The E-Zine is something we are passionate about and it is lovely to receive such feedback. We want it to be as useful to members as possible so please do get in contact with any suggestions and/ or feedback - ezine@das.uk.com or tag us on Twitter @dasairway or @dastrainees.

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September 2022

EXECUTIVE UPDATE | Ravi Bhagrath | Imran Ahmad | Fauzia Mir |

A lot has happened since our last Ezine

Ronnie was also the very deserved recipient

report – alleged lies and misinformation, lots

of the DAS Macewen Medal in 2013,

of resignations, calls for change of leadership

acknowledging his contribution to airway

and even some sinus surgery! Fortunately

management and patient safety. As the DAS

none of that drama applied to the DAS

Executive team we would like to express our

committee, who have continued to work hard

sincere condolences to Ronnie’s family from

as always. There has been progress made in

the DAS committee and the DAS

some key areas of DAS business, in

membership, all of whom have been

particular the DAS Website, educational

impacted by Ronnie’s work.

events, eFONA and dif cult airway databases, DAS Professorships and DAS guidelines. And of course we mustn’t forget to mention all the excellent work by the DAS surveys coordinator, trainee and lay representatives.

There has been a lot of work done nationally and locally to highlight the ‘no trace, wrong place’ campaign and reduce the incidence of undetected oesophageal intubation. DAS has been heavily involved in promoting this important work with the RCoA, we also have

Sadly, we have to share the news of the

representation on various working parties and

recent death of Dr Ronnie Cormack. Ronnie

have recently been asked to endorse a

w i l l a l w a y s b e re m e m b e re d f o r t h e

consensus document on this. The DAS

e x t r a o rd i n a r y i m p a c t o f h i s f a m o u s

committee encourage our membership to

publication and grading scale of direct

promote the ‘no trace, wrong place’

laryngoscopy, which he wrote with John

campaign at their local hospitals and we

Lehane. This was one of the highest cited

would be very happy to be contacted to help.

papers in anaesthesia history and the most commonly used airway grading scale worldwide, there simply can’t be an anaesthetist out there who hasn’t referred to or used the Cormack and Lehane grading.

We have been working on upgrading the DAS website for a while now, progress has unfortunately been slow with many unexpected issues arising along the way, we

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September 2022

have been dealing with them which is why it

of Anaesthetists. This is a very prestigious

has taken so long to complete the upgrade.

award and Professor El-Boghdadly is very

We cannot give you a timeline, however what

deserving of it, he has produced some award

we can say is that we are making good

winning and highly cited work over the past

progress and our DAS website leads and sub-

few years including the consensus guidelines

committee will see this through!

on airway management of COVID patients, the

As conferences start up again following a 2 year hiatus, DAS has been well represented amongst many of them, both nationally and internationally, including the Qatar conference on airway management in Doha, the RCOA

IntubateCOVID series of papers and DAS guidelines on Awake Tracheal Intubation and management of haematoma post thyroid surgery, just to name a few! Many many congratulations Professor El-Boghdadly!

updates in Manchester, ISAIC conference in

Finally, DAS central and the local organising

Milan, GAMC meeting in London and the

team at Newcastle, lead brilliantly by Dr Iftikar

IAMS on line conference. There are many

Pervez, are looking forward to welcoming you

more to come over the rest of the year, this

in October at the rst DAS ASM for 3 years.

just highlights the excellent and important

An excellent programme has been put

work DAS continues to produce.

together with outstanding speakers and

DAS is always involved in important projects all of which are at different stages in their timelines. We are delighted to share that the

sessions planned, there is also an excellent social programme in store too, so do please join us!

nal manuscript for the guidelines on human factors and ergonomics has been submitted for peer review. The guidelines on the ethics

Imran Ahmad, DAS President

of airway management is close to completion

Ravi Bhagrath, DAS Secretary

and work has started on the paediatric,

Fauzia Mir, DAS Treasurer

obstetric and intubation/extubation guidelines.

The safer pre-hospital anaesthesia working group will have their

rst meeting soon and

there are other potential guidelines in the pipeline. We would like to thank everyone involved in the planning and writing of all these guidelines, it is a huge amount of work which takes up a lot of time and we do appreciate your commitment in ensuring they are done.

We are delighted to share the fabulous news that our Scienti c Of cer, Kariem ElB o g h d a d l y, h a s b e e n a w a r d e d t h e Featherstone Professorship by the Association

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SCIENTIFIC OFFICER REPORT | Kariem El-Boghdadly | As we emerge from the darkest

process of grant funding via direct

days of the pandemic, without

application to DAS. Applications

forgetting that we are still not out

for funding of up to £5,000 for

of the woods, we have yet again

studies broadly related to airway

seen academia in airway

m a n a g e m e n t w i l l b e p e e r-

management thriving. Several

reviewed. Further details are

practice-changing publications

available on the DAS website or by

have emerged with more on the

contacting me directly. We have

way. More grants have been

already had a number of

applied for than ever before, and I am in no

applications, and we hope to receive more.

doubt that we will see invaluable evolution in

Reach out for more information on this

patients safety. DAS has continued to play a

today!

vital role in supporting academic

2. DAS Grants via the NIAA. DAS funds up

anaesthesia, with a renewed interest in some

to £20,000, split between large Project

of our academic support through a number of

Grants (up to £15,000) and Small Grants

exciting academic opportunities.

(up to £5,000). Last year saw a single

1. Direct DAS Grants. To ensure continuity

application round, with one application of

and sustainability of grass-roots airway

£15,000 being received. The rst round of

management research, we have a rolling

2022 applications saw 5 applications for a

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total of more than £26,000 requested and,

standing in the eld of airway management

although none were funded, highlights the

as established by outstanding

energy around airway management

contributions through publications, creative

research. The next round is now open -

work or other appropriate forms of

more information and details on how to

scholarship, and through teaching and

apply are available here.

a d m i n i s t r a t i o n . T h e a w a rd w i l l b e announced at DAS ASM – be there!

3. DAS PhD Programme. This Programme gives support to researchers who have a

Our vision remains to continue to cultivate

list of publications that may be suitable to

academia through DAS and airway

put together as a PhD. DAS will support

management, and to begin to support, design

applicants throughout the process of a

and develop our own projects with our

PhD by publication, including funding

enthusiastic, creative and brilliant

support.

membership. Don’t hesitate to reach out and

4. DAS Faculty of Professors. This is an

get involved!

untapped resource that is open to any DAS Member to reach out to for guidance, support or advice on any academic matters, including grant applications and study design. DAS Professor of

Kariem El-Boghdadly DAS Scienti c Of cer Scienti c-of cer@das.uk.com

Anaesthesia and Airway Management for 2022 is an award conferred in recognition of a member’s national/international

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IN MEMORY OF DR RONNIE CORMACK (1930-2022) | Ellen O'Sullivan | Adrian Pearce | Ronnie Cormack was born in 1930 in

(the Macintosh method of a bougie inserted

Rangoon, Burma where his surgeon father

into the endotracheal tube), its universal

was head of military services. He graduated

adoption within training, practising the

from Oxford in 1961 and was an anaesthetic

technique by not adequately lifting the

senior lecturer at Bristol. He was appointed to

epiglottis to simulate a Grade 3 view and

the new MRC unit at Northwick Park in 1972

keeping records. This didactic teaching was

and it was there that he met Dr John Lehane,

very uncommon at that time but was part of

a fellow Consultant. Dr Cormack took early

the culture which was the basis of great

retirement to focus on his research interests

change in airway management over the next

which included statistics.

35 years. In later conversations he revealed

Cormack's great contributions to airway management, for which the Dif cult Airway

that he was most proud of the incorporation of simulated dif cult intubation training.

Society awarded him the Macewen medal in 2013, are contained within his 1984 seminal paper 'Dif cult tracheal intubation in obstetrics' which he co-authored with Dr John Lehane. Until the early 1980s virtually all obstetric anaesthesia cases were undertaken under general anaesthesia. Cormack and Lehane rst proposed that it was possible to classify or sub-divide dif cult intubation by the degree of laryngeal exposure under direct laryngoscopy and this legacy has endured.

The more important messages are often overlooked, but form a very important landmark within UK airway management.

Cormack clearly identi ed the problem that needed solving – dif culty was mostly encountered in a patient with a Grade 3 view and the frequency of this was low enough that many (trainee) anaesthetists were unfamiliar and inexperienced with the situation.

Fig 1: The original illustration of the 4 best views obtainable at laryngoscopy, assuming correct technique from the seminal paper by Cormack and Lehane.

Dif cult tracheal intubation in obstetrics. Anaesthesia 1984; 39: 1105 – 1111

It is in the nature of 'seminal' papers that succeeding generations examine them critically and possibly to the point of rejection.

Their solution was the adoption of the most

But without the genius of the initial paper, the

likely intubation technique to be successful

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detailed discussion could not have taken

laryngoscopy & tracheal intubation. Although

place. Cormack persistently and bravely

various techniques have subsequently

defended his 'solution' over the next 25 years

evolved, this simple system has stood the test

despite changing times and opposition.

of time and Cormack’s name will always be

He had an exceptional, methodical, scienti c mind and 20 years after he retired, at the age of 77, he wrote a blistering editorial supporting

associated with this seminal paper from 1984.

The Society remembers a gentle, caring and enthusiastic teacher.

the Northwick Park drill. It was an opportunity for 'modern-era' anaesthetists to propose different solutions with equal vigour and to promote them with con dence. Next time you

Adrian Pearce, Founding member Dif cult Airway Society

intubate by direct or indirect laryngoscopy

Ellen O’Sullivan, Past President Dif cult

you will inevitably proceed according to the

Airway Society

view of the laryngeal inlet. It was Cormack and Lehane that codi ed that approach. The CL grading system has given us a universal language to communicate and research

Dr Ronnie Cormack receiving the DAS Macewen Medal in October 2013. His citation for the medal by Jaideep J Pandit describes him as “someone who has contributed so much to anaesthesia and in particular in the area of airway management and improved patient safety.” His work, along with that of Lehane, has in uenced the life of every single anaesthetist in immeasurable scale.

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January 2022

BOOK YOUR LEAVE AND REGISTER TODAY

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September 2022

CLINICAL DILEMMA | What Would You Do? |

A 26 year-old man presents with a one-day history of fever, sore throat, and change in voice, and is now extremely anxious and unable to swallow. He is normally t and well, with no regular medications. He has no allergies. On examination:

A. Stridulous and spitting saliva into a cup. Normal mouth opening.

B. RR 34, Sats 96% on room air. Working hard with accessory muscle use and leaning forwards.

Unable to lie at.

C. HR 124, BP 80/40, sweating profusely.

D. GCS 15, very anxious – on the cusp of becoming agitated.

E. Temp 39.9℃.

The ED have applied 100% O2 via a non-rebreathe mask, given a bolus of 1L Hartmann’s, and started appropriate IV antibiotics and given 8mg dexamethasone. They have called you because they think he needs urgent de nitive airway management.

1. What would you do?

2. What would you do if this patient becomes hypoxic (sats 88% on RA) and profoundly agitated/distressed?

3. What would you do if this patient was 6 years old?

What is your plan?

What Would You Do? Contact us on twitter with your thoughts! @dasairway @dastrainees

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WHATWOULDYOUDO? DAS Expert Corner Airway Expert 1: 1. What would you do?

I would start by ensuring the patient is somewhere safe. I would ensure we contact the operating theatres and on-call ENT surgeons, getting theatres ready to receive the patient for de nitive airway management. I would assess if the patient is safe for transfer, and if so, take all airway equipment and drugs that I might need for the transfer, including RSI medications, supraglottic airway devices, disposable video laryngoscope, a range of tracheal tube sizes, and a front-of-neck airway kit comprising a scalpel, bougie and size 6.0 tracheal tube.

Following safe transfer to the operating theatre, I would immediately commence HFNO and increase ow rates to >50 l.min-1 and ensure IV uids are running at the maximum rate. The patient is likely to be unable to tolerate awake tracheal intubation, so I would proceed with full pre-oxygenation whilst getting all of the required equipment ready for an emergency tracheostomy: scrubbed skilled surgeon with the site of tracheostomy marked (ideally using ultrasound), equipment opened and ready to be used, and in ltration with lidocaine with adrenaline. I would have the surgeon ready for the tracheotomy, then after adequate pre-oxygenation, I would induce anaesthesia with high-dose rocuronium, fentanyl and propofol, with a metaraminol ‘chaser’.

My rst choice device would be a videolaryngoscope with a screen that is visible to others in the operating theatre, and I would use the smallest tracheal tube that would be suitable for ICU management. I would have a bougie opened and ready to be used. If I am unable to successfully intubate the patient’s tracheal rapidly, I would insert a supraglottic airway device (iGel) and attempt ventilation through this whilst the surgeon proceeds with a tracheostomy. I would not spend time with multiple attempts at tracheal intubation, and would promptly move forward with tracheostomy insertion if unsuccessful in the rst instance.

Once the airway is secured, I would con rm with capnography, and secure the tracheal tube or tracheostomy, before stabilising the patient with additional lines etc. before transferring to ICU to allow the in ammation and infection to be treated in a more controlled fashion.

2. What would you do if this patient becomes hypoxic (sats 88% on RA) and profoundly agitated/ distressed?

This might require airway management in the ED, and thus I would do the same as in the operating

theatre (HFNO, surgeon ready for tracheostomy, videolaryngoscopy for rst attempt intubation). I would not attempt to provide sedation for agitation, as this may worsen airway obstruction.

3. What would you do if this patient was 6?

I would contact the most skilled paediatric anaesthetist and ENT surgeon, and proceed similarly, recognising that it will be impractical to prepare the patient for tracheostomy awake.

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Airway Expert 2:

Initial impression of this patient is that of someone with impending airway obstruction. He has a high respiratory rate with accessory muscle use. Drooling of saliva, change in voice and unable to swallow are all indicators of airway obstruction/ swelling. Although his saturations are holding well I will ask for a blood gas to assess whether he is getting tired (eg high CO2), and therefore needing intubation sooner rather than waiting for the medical interventions to show their effect and risking his observations getting worse.

I will prepare to intubate him but in a safe environment with help around and an ODP. I will also ask for an ENT surgeon to be present during attempts to secure the airway. Depending on the condition and level of co operation I will consider doing an Fibreoptic nasendoscopy preintubation.

I will plan to do an awake tracheal intubation at this stage with minimal sedation and the operator being the senior, most experienced anaesthetist. I will liaise with HDU/ ITU for post intubation/ operation care for this patient and not extubate him until his airway oedema has settled.

If the saturations drop and his condition worsens I will plan for a general anaesthetic and secure his airway.

In both scenarios I will get ready for a front of neck access as a secondary plan if securing the airway is not as planned and have all the equipment ready with a surgeon in theatres. I will intubate this patient in theatres to avoid any delays in transfer if needed in the event of a failed intubation.

In case of a 6 year old patient, I will seek help from a Paeds anaesthetist who are more experienced with dif cult airways in that age group.

A: normal airway, compared to B: swollen epiglottis in the context of epiglottitis. Image credit: UpToDate http:// uptodate.com

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Airway Expert 3: One of the rst differential diagnoses would be epiglottitis. What seems obvious is that this patient has a worsening airway and is septic.

1. Is the ED the correct place to manage this patient? If yes then: A/B: apply HFNO at 70 L/min C: consider vasoconstrictors (metaraminol, phenyephrine) D: do not sedate, attempt to reassure E: IV paracetamol in addition to the antibiotics Have ENT attempted a nasendsocopy to determine to degree/site of the airway obstruction?

If the patient stabilises with the above manoeuvres transfer to ICU with a low threshold for an airway intervention (to be done in theatre). There may be a place for an elective ATI either VL or FB.

2. If despite applying HFNO the patient is hypoxic and agitated your options are limited.

If you have time to move to a theatre setting that is best. This is a high-risk scenario and the most experienced people are needed - Consultant Anaesthetist, Consultant ENT surgeon, experienced ODP and nursing team (who are familiar with head and neck surgery). a) In theatre with HFNO on at 70L/min, Concurrently have the surgical and nursing team prepared for an emergency tracheostomy (set open, surgeons scrubbed). Set up for a GA - full monitoring, BIS if patient compliant. b) Induce anaesthesia with remifentanil TCI and low rate propofol TCI and cricoid pressure. 1.2mg/kg rocuronium then one attempt at VL . If you have a view then place a 5.0mm ID MLT. If this fails some centres may choose to place a suspension laryngoscope to attempt a view and proceed to HFJV. This has the advantage of avoiding a potentially damaging tracheostomy. c) However, if the above is unsuccessful then a surgical tracheostomy is needed

3. I'd call my paediatric colleagues!

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Airway Expert 4: My working diagnosis is acute epiglottitis. The patient has a compromised airway, which is resulting in worsening agitation, cooperation and hypoxia. The voice change, increased work of breathing, inability to swallow and inability to lie

at are worrying signs and highlight the need for urgent airway

management.

My thoughts are: [1] ATI if patient is cooperative enough [2] GA intubation with a VL and a FB to hand I would perform this in theatre, pre-mark the cricothyroid membrane (using US) and ensure that an experienced ENT surgeon and scrub team were present in theatre. I would explain to the patient that in my hands and practice an ATI is the safest option, but for this to be successful I would need his cooperation.

Plan A: I would start with an ATI and use minimal sedation (as I wouldn’t want to risk over sedation), use HFNO for procedural oxygenation, and take care with topicalisation as there is a risk of inducing laryngospasm and having inadequate topicalisation. I would also downsize the ETT and use a 6.0 tube.

I would do this with the patient sitting bolt upright with suction immediately to hand.

Plan B: If the ATI fails or it is not appropriate then I would move to a high risk GA intubation using a VL and have a FB at hand if I need to do a combined VL/FB intubation.

PlanC/D: If Plans A&B fail then I would immediately move to a surgical cricothyroidotomy or if I had time ask the surgeon to perform a surgical tracheostomy.

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Airway Expert 5: 1. What would you do?

This man is [a] pretty sick and [b] has a critical airway. So he needs A. immediate resus + assessment B. mobilisation of the best team immediately available to ED [must not attempt to move him] - this will depend on where you work, but ideally Senior ENT [or OMFS] with appropriate kit for upper airway + eFONA C. preparation for CVS resus (IV uids; Adrenaline IV bolus + infusion, CVC) D. Neb Adrenaline + HFNO + lots of reassurance (leave sitting of course!). Assessment so far (infective) acute upper airway obstruction + sepsis with CVS compromise. Locate and mark CT membrane E. Quickly discuss as MD team and agree strategy. Options include: 1. Awake FONA (probably a poor choice owing to patient’s mental state); 2. ATI. High risk of failure would make this a relatively poor choice in my view - poor tolerance; failure of LA topicalisation; high risk of complete obstruction.

3. RSI (Fent, Ketamine, Roc/Sux) with MacVL (personal choice, but don’t see obvious indication for hyper-angulated VL) + bougie (expect poor laryngeal view) - this is my likely choice. Ideally, I would use HFNO during prep; then tight- tting FM + CPAP pre-RSI; then BVM ventilation prior to intubation; then HFNO during airway management 4. eFONA - prophylactic cric could be performed pre-induction (narrow or wide) but again probably unwise with risk of complete airway obstruction during procedure.

5. Rescue (failed intubation) - SGAs available (choice of device and size); eFONA - scalpel cric by ENT/OMFS/ED (neck already marked); nal option is upper airway access by surgeons e.g. rigid laryngoscope/bronchoscope.

Use Critically Ill Intubation Checklist. Actively manage human factors and ergonomics (HFE).

2. What would you do if this patient becomes hypoxic (sats 88% on RA) and profoundly agitated/ distressed?

Very little time before cardiac arrest. So, as above but no awake option - straight to GA intubation attempts with rescue options as above; less time perhaps to get the ‘best people’ and ‘best HFE'.

3.

What would you do if this patient was 6?

Again, awake option not available. Pre-oxygenation very dif cult so either do so with parental help or even consider small (sedative) dose of Ketamine to facilitate pre-induction oxygen delivery.

Other main difference is increased risk of eFONA failure (particularly if lack of paeds head & neck ENT surgeon available) so generally favour ETT or SGA attempts over eFONA. RSI. I WOULD paralyse although i know others would not.

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THOUGHTS FROM OUR CASE SETTER | Moon-Moon Majumdar |

When rst setting this case, acute epiglottitis was at the forefront of our minds, and our experts generally thought the same. Since the addition of the Haemophilus in uenzae type b (HIB) vaccine to the infant immunization schedule in many countries worldwide, the annual incidence of epiglottitis in children has decreased overall. However, the incidence in adults has remained stable, and it is now much more likely we will encounter this disease in adults as well.

The pathogens responsible are now more varied and can be polymicrobial. There have even been recent case reports of epi/supraglottitis associated with severe COVID-19 disease. For this reason, the term "supraglottitis" is often preferred, as the infections may affect the supraglottic structures more generally.

Oedema due to infection of the epiglottis and supraglottic structures can be gradually progressive until there is rapidly deterioration, respiratory distress, airway obstruction, and death.

With anti-vax sentiment brought to the fore by the pandemic, previously rare, life-threatening diseases are rearing their heads once again. Australia has seen a recent case of an unvaccinated toddler with severe diphtheria requiring intensive care admission, and in the UK there was a recent case report of similar disease in a 76 year old woman. The above presentation is not dissimilar to a respiratory presentation of diphtheria (just add in the hallmark greyish-white pseudomembrane over the mucous lining of the tonsils, pharynx, larynx, or nares that can extend into the trachea, and severe cervical lymphadenopathy — sometimes so severe there is a 'bull neck' appearance). Cardiovascular instability is a frequent feature in both epiglottitis and diphtheria, in the former this tends to be septic shock, in the latter predominantly cardiogenic shock from diphtheria toxin myocarditis. Early diptheria antitoxin (DAT), antibiotics, and early airway management are the mainstays of treatment: the latter allows mechanical removal of tracheobronchial membranes, and prevents the risk of sudden asphyxia.

We felt this case was a good opportunity to remind ourselves of the urgent management of acute impending airway obstruction. As you can see from our airway experts: there is frequently more than one safe way to skin the proverbial cat. Depending on the situation, some of our experts would transfer to theatre and some would stay in ED to manage the airway. Some would prefer an awake approach — and some think an asleep approach is safer in their hands. The prevailing concepts throughout everyone's answers are clear communication with your team, and careful planning (as far as time allows, depending on how unstable the patient is), so that it's easier to make cognitive progression towards more invasive approaches (for example front of neck).

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PERI-OPERATIVE MEDICINE SERIES: PART 2 | Moon-Moon Majumdar |

In this September 2022 edition of the

useful approach to interpreting

DAS E-Zine, we are proud to present

the '9 panel plot'.

the second in our three part peri-

Finally we nish with a fascinating

operative medicine series.

article on frailty from Dr Anthi

You can nd the rst part in our May

Andrianou (an anaesthetist/

2022 edition here, where we had

intensivist in a former life, she is

three ar ticles: 'Perioperative

now a POPS [Perioperative

Medicine: an Introduction', 'The

medicine for Older People

National Emergency Laparotomy Audit

undergoing Surgery] fellow at Guy's and St

Project', and 'Shared Decision Making'.

Thomas' NHS Foundation Trust) and Dr

This time, we present another three excellent articles. As a starter for 10, we have an in-depth discussion of risk a s s e s s m e n t f ro m t h e P e r i o p e r a t i v e Medicine group at University College London. Dr Alexander Gibson (ST5 anaesthestic trainee at University College London NHS Foundation Trust) and Dr Matt

Jugdeep Dhesi (consultant geriatrician, and POPS clinical lead at Guy's and St Thomas' NHS Foundation Trust). They discuss a gentleman who was referred to the POPS team prior to his head and neck surgery, where comprehensive geriatric assessment and assessment of frailty were key to his surgical pathway.

Oliver (consultant in anaesthesia and

We hope very much that you enjoy reading

perioperative medicine at UCLH, and

and learning from these fantastic resources

associate professor at UCL division of

as much as we have.

surgery and interventional science) talk us through why risk assessment matters, how we can approach it, and how to talk to our patients about it.

Following on from the theme of risk assessment, we delve into the details of CPET with our very own Dr Tom Lawson, DAS Education lead, and consultant anaesthetist at Morriston Hospital in Swansea. Tom looks at the history and process of CPET and shares a practical and

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PERIOPERATIVE MEDICINE: RISK ASSESSMENT | Alexander Gibson | Matt Oliver | What is risk?

As

Why is it important?

doctors

and

Risk assessment is an

anaesthetists the

essential facet of

assessment of risk is

multidisciplinary and

fundamental to our day-

shared decision making.

to-day care of patients.

It

However, as a concept

identi cation and

we are often poor at

management

understanding and

modi able risk factors

allows

the of

incorporating risk into our decisions and often

pre-operatively, the tailoring of anaesthetic

poor at explaining it to others. Risk can be

and surgical technique to the patient and the

considered the chance that something will

safest allocation of resources for post-

happen or the chance that an outcome will

operative care.

differ from that which was expected. It usually refers to the negative implications of an intervention or encounter. In a healthcare setting this commonly means failure or harm including side effects and complications.

Chance is a statement of probability or odds.

Most people feel more comfortable thinking about probability which is expressed as a fraction by dividing the event in question by the total number of possible outcomes. This is often presented as a frequency which should strictly include a time period in its description.

By its nature risk involves uncertainty and the way we perceive risk is governed by our own experiences and personality as well as wider social factors. Risk should also be considered

As many as 15-30% of surgical inpatients s u ff e r f ro m m o r b i d i t y o f s o m e f o r m postoperatively. This likely represents a complex interaction between the indication, nature and extent of the surgical insult, patient factors and the quality of care.1

The

development of post-operative morbidity is associated with increased post-operative mortality, a decline in physical function and quality of life as well as extra healthcare costs.2 Indeed, the development of p o s t o p e r a t i v e m o r b i d i t y i s a g re a t e r determinant of long-term survival following major surgery than pre- or intra-operative factors.3

a product of the probability of the event

Data from the National Con dential Enquiry

occurring and the severity of the implications

into Patient and Death and Intensive Care

of this outcome.

National Audit and Research Centre has demonstrated that approximately 80% of all

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perioperative deaths occur in a high-risk

✦

operative approach and invasiveness;

cohort accounting for 13% of the overall

✦

blood loss, duration;

✦

intraoperative complications;

✦

urgency of surgery (30-day mortality of

surgical workload.4,5 This high-risk group’s overall risk of hospital mortality is as high as 12% and post-operative morbidity as high as 50%.4,6

emergency surgery is 10-fold that of

How do we identify risk factors and predict

elective).1,4

the risk of adverse outcomes?

Functional capacity, is an important predictor

The are multiple ways to estimate the risk of

of how a patient will respond to the overall

adverse postoperative outcomes including an

stress of surgery. This is based on the

assessment of frailty and functional capacity

observation that the increase in oxygen

(covered elsewhere in this edition), the use of

consumption seen after major surgery can

biomarkers and the use of risk scoring

only be sustained at approximately 30% of a

systems and risk prediction models.

patient’s maximal capacity (VO2 max or VO2

Identifying risk starts with a good understanding of the patient presenting for surgery and the nature of the procedure they are presenting for. This should start with a review of the comorbidities of the patient and an assessment of functional status. Repeated studies have demonstrated that several patient and surgical factors independently predict post-operative morbidity and mortality.

These include: ✦

peak). Multiple studies have demonstrated that a VO2 peak < 15 ml/kg/min and/or an anaerobic threshold < 11 ml/kg/min place a patient in a high risk category in terms of morbidity and mortality (See POETTS G u i d a n c e f o r a s u m m a r y o f c u r re n t evidence).7 Whilst formal cardiopulmonary exercise testing with a metabolic cart may not be available to all, surrogates such as the incremental shuttle walk test can be used.

Failing a measured assessment, scoring

age (increasing incidence of mortality > 65-

systems such as the Duke Activity Status

years);

Index allow estimation of functional capacity from a protocoled assessment of activities of

✦

frailty;

✦

reduced functional capacity;

the limitations of self-reported functional

✦

American Society of Anaesthesiologists

capacity.

Physical Status (ASA-PS);

After a thorough history and examination there

co-morbidities including anaemia, obesity,

then exists a plethora of tools that can be

diabetes, congestive cardiac failure and

used to guide ongoing decision making and

cirrhosis (which can increase mortality three

patient care. Biomarkers are playing an

to ve fold);

emerging role in the risk assessment of

✦

✦

history of smoking.

Surgical factors include: ✦

organ system operated on;

daily living, which may improve upon some of

patients undergoing surgery and are now included in national guidelines in North America and Europe.8,9 Raised pre-operative BNP and NT-proBNP have been shown to be

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Fig 1. Preoperative risk assessment and postoperative monitoring ow diagram, from the 2016 Canadian Cardiovascular Society Guidelines on Perioperative Cardiac Risk Assessment and Management for Patients Who Undergo Noncardiac Surgery8 BNP, brain natriuretic peptide; ECG, electrocardiogram; NT-proBNP, N-terminal pro-brain natriuretic peptide; PACU, postanesthesia care unit; PHTN, pulmonary hypertension; RCRI, Revised Cardiac Risk Index. ∗ Signi cant cardiovascular disease includes known history of coronary artery disease, cerebral vascular disease, peripheral artery disease, congestive heart failure, severe PHTN or a severe obstructive intracardiac abnormality (eg, severe aortic stenosis, severe mitral stenosis, or severe hypertrophic obstructive cardiomyopathy). ‡ Timing of surgery refers to emergency surgery (eg, severe trauma, ruptured aortic aneurysm), urgent surgery (eg, hip fracture, bowel obstruction), semiurgent surgery (eg, cancer with potential to metastasize), or elective surgery (eg, knee arthroplasty). £ If physical examination suggests there is an unknown severe obstructive intracardiac abnormality (eg, severe aortic stenosis, severe mitral stenosis, or severe hypertrophic obstructive cardiomyopathy) or severe PHTN, then obtain an echocardiogram before surgery to inform the anesthesiologist, surgeon, and medical team of the type and degree of disease. If the history suggests the patient has an unstable cardiac condition (eg, unstable angina) then discussion with the patient and surgical/medical team is required to decide whether to delay, cancel, or proceed with surgery. § RCRI score (each worth 1 point): history of coronary artery disease, cerebrovascular disease, congestive heart failure, preoperative insulin use, preoperative creatinine > 177 μmol/L, and high-risk surgery (ie, intraperitoneal, intrathoracic, or suprainguinal vascular surgery). ∗∗ Shared-care management refers to a multidisciplinary approach to inpatient postoperative care; this includes the surgeon and a medical specialist (eg, internist, cardiologist, gerontologist), who will help with perioperative monitoring and management of cardiovascular complications.

associated with increased post-operative

With ever larger populations examined and

mortality and cardiac events. Post-operative

validated against and with the ease at which

elevation in troponin is also an important

they can be accessed on mobile devices, risk

prognostic marker and an independent

scoring systems and risk prediction models

predictor of cardiovascular outcomes and

should now be part of everyday anaesthetic

mortality.

practice. These tools use multivariate analysis to examine the association between patient

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characteristics and speci ed post-operative

particularly poor survival and other measures

outcomes in large cohorts of patients.10

such as hospital length of stay. American and

Scoring systems such as the Revised Cardiac

European guidance involve a stepwise

Risk Index (RCRI) use group strati cation or

approach to cardiac risk assessment involving

aggregates of weighted risk factors to predict

an initial assessment using the RCRI and/or

the risk of an adverse outcome which can be

knowledge of the nature of the surgical risk. If

applied to a group of patients. 11 Risk

the case is considered intermediate or high

prediction models allow patient-speci c

risk (> 1% probability of a Major Adverse

parameters to be entered into a model

Cardiac Event) then the functional capacity of

created from the initial logistical regression

the patient should be considered. If less than

providing individual probabilities of risk.12

or equal to 4-metabolic equivalents

Speci c surgical procedures have their own

(approximately 15ml/kg/min) then further tests

risk prediction models to estimate 30-day

including non-invasive tests can be

mortality including EUROSCORE (cardiac),

considered to aid decision making or inform

Nottingham Hip Fracture Score (hip fracture

perioperative care.23,24

re p a i r ) a n d t h e N a t i o n a l E m e r g e n c y Laparotomy Audit risk prediction model

How is risk best communicated?

(emergency abdominal surgery).13,14,15 There

Communicating risk is an important part of

are also tools for speci c post-operative

decision making and consent and this is

morbidity including ARISCAT (pulmonary) and

re ected in updated General Medical Council

SPARK (renal).16,17

guidance on the subject. 25 Information

Many guidelines now also recommend screening for risk of psychological distress, malnutrition and post-operative cognitive dysfunction.18 There are many other wellvalidated tools which have been validated in

discussed should be objective and should focus on factors that are important to the patient. Individually tailoring how we discuss risk with our patients is likely to enhance decision making.

mixed (multi-specialty) populations including

The statistical presentation of risk is a subject

P-POSSUM, SORT, and the ACS NSQIP.19,20,21

in itself, but the importance of clear

These three models are recommended by the

descriptions and framing of risk should not be

National Institute for Health and Care

u n d e re s t i m a t e d . N u m b e r s s h o u l d b e

Excellence for use as part of perioperative

presented as event rates, using frequencies,

patient assessment and consent.22 The ACS

rather than as probabilities using

NSQIP model also generates risk estimates for

percentages. Using a common denominator

13 non-mortality outcomes including system-

should be used where a choice between

speci c insults, re-admission, and discharge

various treatments may affect the risk of the

to a post-acute care facility. However, due to

same event occurring. Supplementing the use

its proprietary nature, this model has not been

of numbers with verbal risk descriptors, such

validated outside its derivation cohort.

as high and low, may also aid understanding

Finally, the assessment of cardiac risk

but they should not be used in isolation.

deserves special focus as post-operative

Standardised numerical de nitions of these

cardiovascular morbidity is associated with

terms should be used as presented in The

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Royal College of Anaesthetists’ infographic on

Glossary:

Common events and risks in anaesthesia

✦

(RCoA).26 This tool also frames these numbers

Risk Evaluation

in a context that might be more familiar to people, which particularly helps when

✦

we tend to be more risk averse when risk is

ARISCAT - Assess Respiratory Risk in Surgical Patients in Catalonia

numbers involved are very small. In terms of framing risk, it is worth noting that as humans

European System for Cardiac Operative

✦

SPARK – Simple Postoperative AKI Risk

✦

P-POSSUM – Portsmouth- Physiological and

framed as negative outcome or loss.

Operative Severity Score for enumeration of

Describing the risk in different ways, such as

Mortality and Morbidity

99 in a 100 people are unlikely to experience an accidental dural puncture during insertion

✦

SORT – Surgical Outcome Risk Tool

of an epidural, may help patients understand

✦

ACS NSQIP – American College of

the risk more without intending to convince

Surgeons National Surgical Quality

them one way or another.

Improvement Program

The risk of adverse postoperative outcomes is not uniform, varying by patient, surgical and process factors. Assessment of risk should now be a routine part of the care of patients undergoing surgery. Combining a review of co-morbidities and an assessment of the type and magnitude of surgery, frailty and functional capacity along with the use of a risk prediction model will allow a comprehensive appraisal of the case to emerge. For it to impact meaningful, patient-centred outcomes it needs to be discussed carefully with both patient and colleagues and acted upon by targeting interventions and resources at highrisk individuals throughout their perioperative journey.

Link to references

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PERIOPERATIVE MEDICINE: CPET | Tom Lawson | If life imitates art, then

Bouny began testing and improving a

perhaps medicine

dynamometer that Marey had constructed in

imitates sport.

As I

1895 at the Champ de Mars winter cycle track.

write this article,

The result was the rst bicycle ergometer1; the

riders from 34

front wheel connected to a brake

countries tackle

dynamometer and the rear replaced with an

stage 11 of the Tour

iron ywheel (Figure 1).

de France, battling from Albertville, up the

southern

approach to the top of Col du Granon in the Serre Chevalier. So, it’s tting that this article about the basics of cardiopulmonary exercise testing (CPET), begins with a Frenchman; Elisée Bouny.

Born 26th June 1872 in Sainte-Foy-LaGrande, Bouny was described as a rare spirit (‘Un si rare esprit’).

Despite studying

medicine at the Paris medical faculty in 1890, he would not however practice clinical medicine; a chronic, and hitherto, unnamed illness that claimed his life at the young age of 28 was responsible for cutting short his medical career. He was, however, fascinated by bicycles (as was most of France in the late 19th century), writing his doctoral thesis on the physiology of the lower extremities in cycling.

Whilst a medical student, Bouny

came into the orbit of the renowned polymath, Étienne-Jules Marey.

Fig 1: Bouny’s Bicycle Ergometer (dated 1896) - From a 2003 PhD dissertation by Yaser Mahfouz Atwa Saad Elgohari.

The current bicycle ergometers used in CPET are much the same, albeit more advanced

One of Marey’s principal concerns was the

versions.

physiology of motion, an obsession with

workload by adding resistance (the method of

which would lead him to invent the

which can vary depending on the bicycle).

‘chronophotographic gun’; in essence the

Together with a metabolic cart (a device that

rst ‘video camera’, becoming a pioneer in

allows for the breath-by-breath analysis of gas

the emerging eld of cinematography.

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They generate a measurable

exchange parameters) and with the use of ow

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sensors and other monitoring equipment such

model can be helpful for patients to

as ECG, blood pressure cuffs and pulse

conceptualise what this means: -

oximetry, a whole host of physiological

✦

parameters can be measured and derived.

Green light – low risk, normal recovery expected and can proceed.

So why CPET?

✦

Amber light – intermediate risk, either in

The use of CPET has expanded greatly in the

terms of degree/complexity of surgery, or in

last two decades and is used by professionals

terms of tness and comorbidities. Potential

across a wide array of disciplines. Principally,

for prolonged / incomplete recovery and

the main uses of CPET are:

need for further investigation, optimisation

✦

✦

Red light – high risk. Potential that surgery poses a greater threat to life than underlying

✦

Peri-operative risk strati cation;

✦

Investigation of dyspnoea of unexplained

condition.

origin; ✦

and appropriate post-operative support.

Assessment of exercise capacity and / or limitation;

Increasingly, CPET is being adopted by various surgical specialties as part of their

Disease prognostication.

guidelines for the pre-operative work-up of

In the realms of anaesthesia, the assessment

patients for surgery.

Historically, colorectal,

of exercise capacity and peri-operative risk

vascular and thoracic surgery have led the

strati cation go hand-in-hand, although more

way in requesting CPETs for their patients.

recently CPET services and peri-operative

It might seem odd, for an article on CPET to

physicians are seeing more medical patients,

appear in an e-zine primarily aimed at those

not just for investigation of dyspnoea, but also

interested in airway or head and neck

the assessment of long-COVID, determination

anaesthesia, but there is growing evidence

of baseline function in patients with

that CPET can be performed for patients with

progressive cardiac disease, etc.

head and neck cancers2,3.

CPET ful ls a key part of the pre-operative risk

obstruction and head and neck cancer do not

discussion and can help inform shared-

appear in the lists of absolute or relative

decision making. As part of a dialogue with

contraindications for CPET from the American

patients, it is important to explain to them that

Thoracic Society/American College of Chest

‘when someone undergoes major surgery,

Physicians joint statement on CPET4, although

their body incurs a debt. The ability to repay

it is clear that care and caution should be

that debt depends on several factors; age,

taken when testing such patients.

Indeed, airway

Whilst

tness, co-morbid state, type of surgery, etc’

CPET for such patients may be unusual

which CPET can help determine. Whilst CPET

outside of major specialist centres, it may

may not necessarily be able to determine a

prove to be a growing area in the future. What

speci c percent risk of certain complication, it

follows is a basic introduction to what a CPET

can be useful more generally to stratify

is and how a non-expert can interpret a test.

patients into broad risk groups. A traf c light

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A CPET consists of 4 basic (and largely

activity; cardiac output, pulmonary blood ow,

standardised) phases (shown in gure 2): -

ventilation, pulmonary gas transfer and

1. R e s t – 2 - 3 m i n u t e s o f b a s e l i n e measurements

peripheral blood ow. Thus, we measure and derive a variety of parameters including: ✦

Oxygen consumption (VO2)

with no pedal resistance. Start to measure

✦

Carbon dioxide production (VCO2)

response to movement and allow patient to

✦

Respiratory Exchange Ratio (VCO2/ VO2)

✦

Tidal volume (VT)

✦

Respiratory rate (RR)

✦

Minute ventilation (VE)

✦

Ventilatory equivalents for Oxygen (VEVO2)

2. Unloaded cycling – 2-3 minutes of cycling

attain needed pedal cadence (approximately 60 revolutions per minute).

3. Loaded cycling – workload increases in a ramped fashion.

Patient continues until

unable to maintain adequate pedal cadence (usually due to leg fatigue or joint

and CO2 (VEVCO2)

pain, less common reasons include breathlessness or test terminated by

✦

Partial End-Tidal Pressures of Oxygen and Carbon Dioxide

clinician).

4. Recovery – 2-5 minutes of measurements

✦

ischaemic changes.

to assess the response to stopping exercise (e.g. autonomic tone leading to

Heart rate (HR), rhythm and potential

✦

Oxygen Pulse (VO2/HR)

✦

Work rate (WR)

✦

ΔVO2/WR

to increase the various physiological

✦

Oxygen saturations (SpO2)

mechanisms required to match increased

✦

Blood pressure

heart rate to decrease at an appropriate rate).

In essence the normal response to exercise is

energy demands from increased muscular

These parameters are presented as a set of 9 panels, each with a different plot. There are several different ‘9-panel plots’, but effectively they present largely the same information in different orders. For simplicity we will examine the standard Wasserman 9-panel plot which is commonplace in the literature ( gure 3), most of the parameters are plotted against time (but some can also be plotted against workload).

Fig 2: Schematic representation of different phases of CPET

Let’s look at each plot in order.

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Figure 3: a CPET for a normal subject

Plot 1 – VE vs time ✦

✦

with increasing workload.

Normally, minute volume should increase with increasing workload.

✦

VE should reach >80% predicted.

✦

Failure to do so implies ventilatory limitation

✦

HR should reach >80% predicted (usually >90%).

e.g. COPD. ✦

The oxygen pulse (VO2/HR) is a surrogate marker of stroke volume.

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Heart rate/cardiac output are the factors that usually limit exercise capacity.

✦

Plot 2 – VO2/HR and HR vs time

Usually, both VO2 and HR should increase

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September 2022

Normally, VO2/HR increases with exercise, but the gradient may start to

✦

atten off

towards peak exercise as any increase in

retention. ✦

cardiac output is due to increasing HR and

ventilatory function with an inability to

A low oxygen pulse or early plateau can

clear CO2 - which is either pulmonary in

indicate cardiac disease

origin (from increased in dead space / tidal volume ratio) or cardiac in origin

Plot 3 – VO2 and VCO2 vs time ✦

✦

✦

(seen with a low PaCO2, in which there is

Under normal circumstance, VO2 is greater

a low ‘driving pressure’ to remove CO2

than VCO2 at rest, and remains so during

from alveolar gas – i.e. cardiac failure is

exercise until the anaerobic threshold (AT)

unable to maintain an adequate diffusion

is reached.

gradient for CO2).

Peak VO2 should be >80% predicted

✦

inef cient ventilation and has been

capacity).

shown to be a good predictor of

Of note, in gure 3 resting VCO2 is actually

morbidity and mortality.

Plot 5 – VCO2 (and HR) vs VO2

degree of anticipatory hyperventilation ✦

before exercise.

✦

reached.

of increasing exercise.

✦

increases, as a way of compensating for the metabolic acidosis that ensues due

with work rate slope.

to the increase in lactic acid production

A shallow VO2 rise usually points to a

associated with increased anaerobic

cardiovascular abnormality.

metabolism.

An abrupt

attening of VO2 slope can

✦

on the VCO2 curve at which the gradient

and needs to be correlated with the

steepens. ✦

Normally, there is a fairly linear relationship

✦

Failure of AT to exceed 40% implies

between minute ventilation and VCO2 which

cardiovascular abnormality (e.g. low

represents ef cient CO2 clearance.

cardiac output, anaemia, peripheral

The gradient of this curve should be <35.

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This is normally >40% of the predicted peak VO2

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The AT is the VO2 at the in ection point

suggest the onset of cardiac ischaemia

Plot 4 – VE vs VCO2

✦

After which VCO2 abruptly

VO2 should rise in a linear fashion, in-line

exercise ECG.

✦

VCO 2 should steadily increase with increasing exercise until the AT is

means of seeing how VO2 varies in the face

✦

This is the primary plot that is used to determine the AT.

Sometimes this curve has work rate superimposed, this can be useful as a

✦

A curve with a gradient >36 indicates

( < 8 0 % s u g g e s t s re d u c e d e x e rc i s e

greater than VO2 and this is likely due to a

✦

Whereas, a steep curve (i.e. high minute ventilation with low VCO2) implies poor

not stroke volume. ✦

A shallow curve may be seen in CO2

vascular disease, etc).

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Plot 6 – VEVCO2 and VEVO2 vs time ✦

✦

ventilation increases primarily due to

Ventilatory equivalents are unitless values

increasing tidal volume, rather than

that are used to express the ef ciency of the

respiratory rate. As intensity increases, a

lungs in terms of volume of ventilation

point arrives at which tidal volume cannot

required to either consume or eliminate a

increase any further (lung units are

volume of gas (oxygen and carbon dioxide

maximally recruited), hence any increase in

respectively). ✦

minute ventilation is due to increasing

At rest lung apices are better ventilated than

respiratory rate – the result is a ‘dogleg’

perfused.

curve.

As exercise increases, apical

pulmonary vessels are recruited and as such their V/Q ratios improve. The result is

✦

✦

Plot 8 – RER vs time

showing improving V/Q matching.

✦

VEVO2 begins to rise at the AT, because

After the AT, lactic acidosis is initially ✦

>1.0 due to the increase in VCO2.

ventilation must increase to eliminate CO2 as ✦

Of note in gure 3 the resting RER is >1.0 –

acidosis, because the buffering capacity of

this is likely due to anticipatory

blood has been exhausted – this is the

hyperventilation – if we correlate this with RR

respiratory compensation point (RCP) –

shown on plot 9, we can see a resting RR of

which can be very subtle on this plot.

18-20.

The VEVO 2 plot can be used as an

✦

A failure of RER to rise above 1.0 implies the failure or inability to mount a lactic acidosis.

additional means of cross-checking the

✦

As exercise progresses both VCO2 and VO2 increase, and beyond the AT RER must be

However, at some point

a means of dealing with the metabolic

Normally, VCO2 is slightly less than VO2 at rest and resting RER is <1.0

isocapnic buffering, as VEVCO2 is largely unchanged.

The respiratory exchange ratio (RER) is the ratio of VCO2 to VO2.

✦

buffered by HCO3- - this is known as

✦

A shallow curve implies obstructive disease.

a gradual fall in VEVCO2 and VEVO2

VO2 cannot rise further. ✦

Usually, at lower intensity exercise, minute

accuracy of the AT from plot 5.

Plot 9 – PETO2 and PETCO2 (with RR and

Additionally, the nadir of both VEVO2 and

SpO2) vs time

VEVCO2 represents the point at which the

✦

This plot shows how the end-tidal partial

lungs are most ef cient. If the lowest value

pressures of oxygen and carbon dioxide

for VEVCO2 is >30 it implies poor gas

change time during exercise.

exchange (e.g. pulmonar y vascular

✦

disease) or inef cient ventilation (e.g.

The two curves are essentially mirror images of each other.

COPD). ✦

Plot 7 – VT vs VE

PETO2 should fall as more oxygen is extracted from air, until the AT after which end-tidal O2 increases because ventilation

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September 2022

increases without an additional increase in

CPET is a fascinating topic and an area

VO2.

within anaesthesia / perioperative

PETCO2 however, gradually rises with exercise due to increased production.

After the RCP, ventilation increases to compensate for acidaemia and end-tidal CO2 begins to fall.

✦

medicine, in which anaesthetists can indulge in watching physiology change in real-time (without the need of a syringe of propofol or a surgeon’s knife), can aid in the appropriate allocation of healthcare resources and can help patients to make

This plot can also be used to correlate AT,

informed decisions about their care.

which occurs at the nadir of PETO2 and

hope you’ve found this helpful and if you’d

highest PETCO2.

like more information, please feel free to

I

email me (thomas.lawson@wales.nhs.uk) or tweet me (@vapourologist).

Link to references

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PERIOPERATIVE MEDICINE: FRAILTY | Anthi Andrianou | Jugdeep Dhesi | Preoperative assessment

m o re c o m p l e x i n t h e

of frailty in surgical cancer

context of old age, frailty

patients:

and multimorbidity, as demonstrated in this case

Delivering Perioperative

presentation.

medicine for Older People undergoing Surgery

Case presentation

(POPS) care for a patient

An 87 year old male

with head and neck

patient was referred to the

cancer.

Perioperative medicine for Older People

Introduction

undergoing Surgery (POPS) preoperative

It is well known that the incidence of most malignancies increases with age. This is also true for head and neck cancer (which is the

clinic in preparation for hemiglossectomy with neck dissection and free ap for a T3N0M0 tongue squamous cell carcinoma.

8th most common cancer in the UK with)

The tumour was sizeable (4 cm), located at

22% of all new head and neck malignancy

the right side of the tongue causing problems

diagnoses presenting in people aged 75

with breathing (patient had to sleep sitting up

years and over.1

and had suffered incidents of saliva

The treatment of most head and neck malignancies includes a combination of major/complex surgery and/or chemo/ radiotherapy. These interventions are

aspiration) and swallowing (he had lost a signi cant amount of weight). Both of these symptoms had led to signi cant functional deconditioning.

effective in achieving cure with 19 - 59% 10-

In terms of co-morbidities, he had well

year survival but can be dif cult to tolerate for

controlled

older patients.1 Surgical management of

Bendro umethiazide and had stopped

head and neck cancer can be particularly

smoking more than 20 years previously. From

problematic, as there is permanent alteration

a social perspective, he lived alone with no

of the anatomy and physiology of essential

relatives in the United Kingdom and although

structures and function including airway and

he had some older friends they were unable to

eating and those crucial to maintaining

provide support. He remained independent in

quality of life including communication.

personal care and was able to manage his

This can mean that patients need to manage tracheostomies, speaking valves, feeding

deterioration in day-to-day function.

tubes and pumps and may have to re-learn

Frailty Assessment

skills such as speaking. These issues can

F r a i l t y i s d e n e d a s a p ro g re s s i v e ,

generate interesting dilemmas which can be

multidomain deterioration in functional reserve

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September 2022

Fig 1. Guideline for Perioperative Care for People Living with Frailty Undergoing Elective and Emergency Surgery. Joint guideline Centre for peri-operative care/British Geriatrics Society, 2021.

which increases vulnerability to even minor

the underpinning methodology in geriatric

external stressors resulting in adverse

medicine and is the gold standard for

outcomes (mortality, prolonged hospital stay,

assessing frailty. It is a multidimensional and

loss of independence, increased costs of care

ideally multidisciplinary tool, through which

etc).2,3

the following components are assessed and

Frailty needs to be considered by all

healthcare professionals as it can affect decision making at every step of the perioperative pathway.

In 2021, the Centre for Perioperative Care (CPOC) and British Geriatrics Society (BGS) published guidelines on perioperative care for

optimised.5 CGA Scores and Interpretation This list is not exhaustive, but provides a avour of frequently tools and scores used in CGA based services.

people living with frailty undergoing elective

Frailty Scores

and emergency surgery.4

Clinical Frailty Score (CFS): Expressed as

Applying the recommendations of the

Scale 1 – 9 (1 – very t, 9 – terminally ill) and

guideline in this case, the patient underwent

accompanied by a visual aid, (Rockwood et

preoperative Comprehensive Geriatric

al., 2005). Clinical Frailty is de ned as CFS >

Assessment and optimisation (CGA). CGA is

4 and is associated with higher risk of

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Fig 2. Comprehensive Geriatric Assessment and various Frailty Scores

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postoperative complications.6,7,8,9,10

screening tool with high sensitivity and

Edmonton Frailty Score (EFS): Expressed as Scale 0 – 17 , this is a multidimensional, performance based frailty assessment tool, designed to be used by non-geriatricians in a variety of settings (outpatients’ clinics, at the bedside etc). EFS>6 is associated with higher risk of postoperative complications in a heterogenous vascular surgical population.11,12,13,14

speci city for detecting mild cognitive impairment. Scores below 24 are considered abnormal.24,25,26,27 Functional status: Duke Activity Status Index (DASI): Expressed as a scale of 0 – 58.2, this self-administered questionnaire examines 12 types of physical activity and correlates well with oxygen uptake a n d t h e re f o re M e t a b o l i c E q u i v a l e n t s

Mood/Anxiety:

(METs).28,29,30,31,32

Hospital Anxiety and Depression Scale

Nottingham Extended Activity of Daily Living

(HADS): Expressed as scale 0 – 21 for each

Index (NEADL): expressed as a scale of 0 –

component, was developed in 1983 to identify

66, this self-administered questionnaire

anxiety and depression among patients in

provides an extended ADL score that is

nonpsychiatric hospitals. This scale excludes

correlated with more complex measures of

physical symptoms of anxiety and depression

disability. It assesses 21 activities in four

which can overlap with physical illness. High

categories: mobility, kitchen activities,

HADS scores have been associated with

domestic and leisure activities.33,34,35

higher risk of postoperative delirium and increased mortality and major morbidity in some surgical populations.15,16,17,18

turn and return to the chair. Patients with Attention, Abbreviated

Mental Test – 4, Acute change): Screening tool for the detection of delirium, designed for routine

assess mobility, balance and gait. Patients are instructed to raise from a chair, walk 3 meters,

Cognition: 4As Test (Arousal,

Time Up And Go (TUAG): a timed test used to

use.19,20,21,22,23

TUAG of greater than 20 seconds are at increased risk of falls.36,37 Gait Speed: Timed test where an individual is timed walking 4m. Gait speed less than 0.8m/

Montreal Cognitive Assessment (MoCA): Expressed as a scale of 0 – 30, is a brief

sec is associated with adverse postoperative o u t c o m e s ( m o r b i d i t y, m o r t a l i t y, institutionalisation).38,39,40

Fig 3. Case scores for this patient

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Nutrition:

Shared decision making: The case was

Malnutrition Universal Screening Tool (MUST): is a screening tool used to identify adults who are malnourished, at risk of malnutrition or obese. A score > 2 signi es high risk of malnutrition.41,42 Case Discussion: Assessment and optimisation

discussed the same day with the surgical team, above concerns were considered and the patient was scheduled to be admitted in the hospital that same week to monitor the airway and start enteral nutrition via NJT. Admission and discharge: successful operation, admitted to intensive care for 48 hours for monitoring mainly of airway and

Following Comprehensive Geriatric

respiratory function, but he did not require any

Assessment, the major issues were identi ed.

organ support. Eventually discharged back to

✦

New diagnosis of COPD: increased risk of

his own house with carers’ support, dietitian,

postoperative pulmonary complications.

speech and language, and physiotherapy

Started on LAMA/LABA according to

input in the community.

national guidelines, advice on nebulised

Conclusion

therapy to be used post procedure; taught respiratory exercises by physiotherapist. ✦

✦

✦

As shown, the CGA provided all involved professionals with a list of issues that could be

Normocytic anaemia: deplete in vitamin B12

optimised, monitored, or anticipated during

folate and iron. Coeliac screen negative and

the perioperative period, in order to avoid

attributed to poor nutrition. Optimised using

complications, increased length of stay or

intramuscular vitamin B12, oral folate and

barriers to discharge. Moreover, this detailed

intravenous iron.

assessment gave the patient the opportunity

Mild cognitive impairment: with implications

to understand better and in depth the

regarding capacity to consent and ability to

implications of a major operation like this and

manage post-operative devices and

the special demands of having to manage a

equipment. Risk of delirium reduced

variety of equipment and learn new skills. His

through optimisation of mild hyponatraemia

admission date was expedited, he had a

by

stopping Bendro umethiazide and

successful operation, and he was discharged

introducing Amlodipine. Delirium pathway

to his own house with support, eventually

used and shared with patient and ward

returning to previous baseline in

team.

approximately four months.

Malnutrition: Hospital dietitian involved, provided supplements and an NJT insertion

Link to references

was organised. ✦

Lack of social support: with increased risk of delayed discharge from hospital. Proactive occupational therapy involvement to facilitate effective timely discharge.

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Further Learning Course: Perioperative Care of Older People Undergoing Surgery | British Geriatrics Society (bgs.org.uk) – E learning

Podcasts: Anaesthesia 2018 podcast | geriatric care and the value of teamwork | The Royal College of Anaesthetists (rcoa.ac.uk) – Prof Weller and Prof Dhesi - 2018 TopMedTalk - Perioperative Frailty with Jude Partridge | EBPOM 2020 London (google.com) Podcast: Frailty | The Faculty of Intensive Care Medicine ( cm.ac.uk) – Frailty and Critical Care Episode 1.1 – Comprehensive Geriatric Assessment – The Hearing Aid Podcasts Episode 1.2 Delirium – The Hearing Aid Podcasts Episode 2.1 Frailty – The Hearing Aid Podcasts Episode 3.08: Peri-operative care – The Hearing Aid Podcasts Episode 7.02 ‘Silver’ Trauma – The Hearing Aid Podcasts

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#JANUAIRWAY 2022 THE COMPILATION | freely available and downloadable on issuu |

AVAILABLE HERE!

@dastrainees @vapourologist #DASeducation

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MASTERCLASS WITH DAS: ABSTRACTS | Natalie Silvey | May saw the

rst of our planned

Alistair McNarry, Joint DAS and

webinar series, Masterclass with

RCoA Lead for Airway Leads and a

DAS, and we kicked off with a really

veteran of abstract judging then took

insightful session on Abstracts.

us through an enlightening look at what happens when you press

Submitting an abstract to a

submit on your abstract and the

conference can be a daunting

judging process. His top tips around

process but it is a great way of

the submission process:

highlighting the amazing work you are doing, and also valuable points for

✦

Check you have followed the instructions

applications and the all important evidence for

✦

Make sure you have carefully typed in your

sign off of curriculum competencies.

e m a i l a d d re s s s o y o u re c e i v e a n y

Kariem El-Boghdadly, our Scienti c Of cer at DAS, kicked things off with a talk on 'How to

correspondence. ✦

Write a Good Abstract'. His key principles to

submit.

abide by: ✦ ✦

Know your audience – review the author

successfully submits an abstract will get

your work for your reviewers and readers.

one.

✦

Be concise – less is more.

✦

Keep it simple – simplicity is key to making

✦

sure your message is clear and absorbed by the audience.

✦

results and check your punctuation.

Abstracts for the DAS conference will be

Be selective – think about what you are

are scored independently. There is a quality

delivering so your message isn’t lost in a

assurance process to make sure the marks

sea of information and do not overreach in

are consistent. For those abstracts which

your conclusions.

score particularly highly, 15 –20 are reviewed

Spell check – wrong spelling can undermine you submit.

to select the oral presentations. This takes a huge amount of time, and I would like to give a personal thank you to all involved in the process.

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Make sure you have clear consent, clear

judged usually by 3 different people and all

your work, run through a spell check before

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For DAS 2022 submissions – check you get a con rmation email: everyone who

guidelines carefully and follow them. Pitch

✦

If you have any questions ask before you

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Our very own DAS education lead Gunjeet

The abstract submission for DAS 2022 is now

Dua and immediate past president of DAS

closed and the judging process is ongoing.

Barry McGuire, gave their insights on what

We are looking forward to our rst in-person

makes a great abstract, poster and oral

meeting since 2019 and I particularly will be

presentation. In short – sell yourself and your

looking out for the posters and oral

work. This is your opportunity to show what

presentations to see the incredible work that

fantastic work you have been doing and it a

will be presented at the conference.

part of the conference we really value because it is an opportunity for us to learn from each other.

Rebecca Davenport, Specialities Societies

Originality is a bene t so think about your project in advance before you even start.

✦

Manager, for her invaluable support.

Please watch out for the announcement of our

Put your mind in that of the audience so you don’t lose your audience when presenting your project.

✦

a huge thanks to Helen Aoife Illiff for managing everything behind the scenes and

Some key pearls of wisdom: ✦

The webinar received excellent feedback, and

next Masterclass with DAS as well as other webinars and events from DAS education. Let us know what topics you wish to learn about in the future! Tweet us @dastrainees @dasairway

Try to present locally rst, this gives you an

or email us at trainee@das.uk.com

opportunity to practice and re ne your presentation.

We

nished with a panel discussion which

included Sharim Khan, the abstract lead for DAS 2022. One thing our panel all agreed on whether you are submitting an abstract, producing your poster or giving an oral presentation, focus on your one clear message from your work and focus on the impact of this.

A piece of key information was given by Kariem El-Bogdadly - if you submit something as an abstract you can then submit it for publication in a journal as long as you declare that the work has been presented before and give details of this. You cannot do it the other way around, i.e. you cannot have data published and then submit an abstract of the same work.

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DAS WEBINARS 2022 | Gunjeet Dua |

MORE PROGRAMME ANNOUNCEMENTS COMING SOON!

For all members of the multidisciplinary team

#LearnTogether @dastrainees #DASeducation

Members will be emailed details of upcoming webinars including registration details from the DAS Secretariat. Please ensure your email address is up to date so as not to miss information on events.

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DAS TRAINEE COMPETITION WINNERS 2022 | Congratulations to everyone who entered! |

This year, the standard of entries to the DAS trainee competition has been incredibly high. This year's title was 'Airway Training of Dreams', and we invited trainees to interpret that however they wished — in whatever media they wished. For the rst time in 2022, we had two categories to enter: creative writing, and creative media.

1st Prize Creative Writing: Dr Asya Veloso Costa 1st Prize Creative Media: Dr Helena Jennison However, the standard of submissions was so high the judges ended up awarding 3 extra prizes for:

1. Best podcast - Dr Eoin Dore and Dr Duncan Brouwer-Kemp 2. Best video - Dr Jo Lau 3. Best photography - Dr Hannah Leaman We, as fellow trainees, are extremely proud to present their work here in the eZine. Enjoy!

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1ST PRIZE CREATIVE WRITING

AIRWAY TRAINING OF DREAMS | Asya Veloso Costa | Airway training shouldn’t be

exposure to clinical cases allows

dif cult. Yet numerous trainees

doctors to develop their own

feel inadequately experienced

judgement. However, this model

in what is arguably one of the

results in signi cant variability

most fundamental areas of

based on the skill and

anaesthesia. Airway

engagement of the supervising

emergencies have the potential

anaesthetist. Case mix, and time

to have catastrophic

pressures in theatre also have a

consequences such as brain

role to play, resulting in dissimilar

injury and death. The fourth

learning experiences between

National Audit Project (NAP4)

trainees.3 There is also concern

found that education and training was a

that with the increasing use of supra-glottic

causal or contributory factor in approximately

airway devices (SADs), trainees are having

studied.1

fewer opportunities to strengthen core airway

half of the adverse airway events Their

ndings recommended airway training

for both trainees and trained anaesthetists. So how do we maximize training opportunities when these dif cult airway events are rare, and when we cannot guarantee uniform experience across the board? Ultimately, it comes down to repeated exposure and familiarity with the equipment and human factors in emergency situations, which can be achieved via simulation. Additionally, empowering trainees and trainers to make the most of the opportunities that do arise and creating a positive learning culture is crucial.

skills such as mask ventilation and intubation.

Simulation is well-established within medical education as it allows the same opportunity to learn by doing without harming patients. It is a powerful tool which is proven to advance educational goals via experiential learning.4 Simulation is also incredibly well-received by anaesthetic trainees, with 90% of trainees supporting its use.5 The Royal College of Anaesthetists (RCOA) Simulation strategy calls for an increasing role of simulation in training, with a view to integrate simulation where possible into the new 2020 curriculum.6

“For the things we have to learn before we can

The RCOA hopes to eventually introduce a

do them, we learn by doing them.”

system where minimum standards for essential clinical skills including failed

― Aristotle2

intubation drill and front-of-neck access

Classically, airway training was acquired “on

(FONA) should be demonstrated using

the job”, within an apprenticeship model of

simulation-based resources. This could occur

learning. For an incredibly practical discipline,

prior to rst performance of the skill or as part

learning by doing is fundamental, and having

of continuing assessment and development in

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different stages of training. This would not only

The argument against simulation is that it is

improve patient safety but provide a set

just not the real thing. Simulators have been

provision of airway opportunities nationally.

progressively increasing in delity, and these

Technology is becoming increasingly advanced, and we are seeing this re ected in the equipment available for anaesthesia in the last few decades. Videolaryngoscopes, which are becoming increasingly prevalent, are recommended by the Dif cult Airway Society (DAS) as part of their dif cult airway algorithm but can also be powerful teaching tools.7 There is evidence to show that novice

come at a price. However, simulation has the potential to be incredibly cost-effective if aimed intelligently,4 and it can integrate equipment, procedures, guidelines, and human factors into one learning experience.

The ideal airway training would use all these factors in a cohesive and safe experiential learning environment at regular intervals in structured courses.

anaesthetists who were taught using

Currently, airway workshops and courses run

videolaryngoscopy had more rapid acquisition

by major organisations such as DAS are

of intubation skills.8 Recording of intubations

available, but for limited numbers, and local

can also be used for structured feedback.9

training is encouraged. Despite this, a recent

New devices and techniques are becoming increasingly available, but has training kept up with this pace? NAP 4 highlighted several cases where awake bre-optic intubation, now commonly referred to as awake tracheal intubation (ATI), was not used where it was indicated despite being the gold-standard technique in dif cult airways. This may

national survey found that 16% of hospitals did not offer any airway training workshops. Of those that did, over half were run less frequently than annually. 12 Ultimately, repetition is the key to mastering any expert technique, and skills that are not used will decline.13 This again makes a case for having regular simulations throughout training.

potentially be down to inexperience because

“The only real mistake is the one from which

of lack of opportunity and resulting reluctance

we learn nothing”

to use an unfamiliar technique. Simulation would provide opportunities for trainees to

― Henry Ford2

work on this core skill.

Simulation is bene cial not only at the

We are also seeing the emergence and

individual level, but to enhance team-based

renewing of increasing numbers of national

working. Human factors are recognised as

guidelines, such as the DAS guidelines for ATI

vital contributors to any emergency scenario

and for unanticipated dif cult intubation in

and expecting trainees to manage dif cult

adults.7,10 These provide widespread access

airways without factoring this in is unrealistic.

to best-practice and useful cognitive aids,

These simulation workshops would ideally be

which have the power to improve technical

multidisciplinary and encourage discussion on

per for mance and decision making in

human factors in debrief. They should involve

anaesthesia. 11 Guidelines also promote

trainees, operating department practitioners

consistency in training, and these can be

(ODPs) & anaesthetic nurses. Debrief with

reinforced in simulation.

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self-re ection and observer feedback

Learning is an experience, one that should be

promotes learning in this environment.14

stress-free and enjoyable. Learning therefore

So, this brings me on to re ect on one of my own experiences as a core trainee. I recently had a fantastic training experience during an airway list in a large tertiary centre. I was asked to assess an elderly patient with severe neck

b ro s i s s e c o n d a r y t o p re v i o u s

radiotherapy following an oral squamous cell carcinoma excision. This was an airway like none I had seen before. After my assessment, I presented my ndings to the consultant, who then proceeded to give me structured feedback and describe their strategy for assessing such an airway. We agreed the safest plan for this patient would be an awake tracheal intubation. The consultant identi ed one of the senior registrars who required airway experience and asked them to join us to perform the awake intubation whilst I topicalised the airway.

occurs best in a system which looks after doctors. A work satisfaction survey of anaesthetic trainees in 2019 found that roughly one

fth of trainees had high

depression risk. Prevalence of perceived stress (37%) and burnout risk (25%) were even higher and these often co-existed.15 Wellbeing is a buzzword that comes up time and time again, and it is important we take a holistic view of training. Doctors can be empowered to be better and take control of their training if they are treated better. Looking after staff wellbeing is not only a moral responsibility but has a signi cant impact on performance and productivity in organisations.16 This is important not only at an organizational level but also at a more personal one. Educational supervisors should regularly check in with trainees to re ect on challenging cases where there are lessons to

What was striking was the different levels of training that were occurring in tandem during this case. I had performed an airway assessment, obtained useful feedback, and learnt about topicalisation using the DAS ATI guidelines, whilst the consultant actively identi ed a great learning opportunity for one of the registrars to perform a procedure.

Being able to observe the registrar performing a bre-optic intubation was also bene cial for me at my level of training. There was effective communication within the anaesthetic team, with the surgical team, and the atmosphere was an incredibly positive one. I went home that day feeling exhilarated, but this isn’t a common feeling in the current climate.

be learnt.

What constitutes the ideal airway training? My experience is one that I will not forget – it has encouraged me to write this essay, take control of my training and sign up to an airway course. Key ingredients include a motivated trainee, a passionate trainer, maximization of a clinical case where there is learning opportunity available, and targeted training based on level and experience. Regular simulation focusing on equipment, guidelines and human factors is essential to ensure core skills are maintained. Airway training shouldn’t be dif cult, and when done right it can really feel like a dream.

“Study without desire spoils the memory, and it retains nothing that it takes in”

Link to references

― Leonardo Da Vinci2

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1ST PRIZE CREATIVE MEDIA

AIRWAY TRAINING OF DREAMS | Helena Jennison |

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TRAINEE COMPETITION | Extra prizes | The judges were so impressed with the standard of entries, particularly in the creative media category, they have decided to award 3 additional prizes

Best podcast - Dr Eoin Dore and Dr Duncan Brouwer-Kemp https://t.co/Q3F0B566GS

Best video - Dr Joanna Lau

Best photography Dr Hannah Leaman

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JOURNAL CLUB | Recommended Reads | Welcome to the DAS Journal Club - Recommended Reads. Papers are chosen by members of the DAS committee, with short citations/summaries by members of the ezine editorial team. This edition's recommended reads come from Kariem El-Boghdadly with summaries

by Natalie Silvey. We welcome members feedback and thoughts on the papers featured - please tweet us @dastrainees or @dasairway or email us at ezine@das.uk.com.

Effect of Non-Invasive Respiratory Strategies on Intubation or Mortality Among Patients With Acute Hypoxemic Respiratory Failure and COVID-19: The RECOVERY-RS Randomised Clinical Trial. ✦

Perkins GD, Ji C, Connolly BA et al. Effect of Non-Invasive Respiratory Strategies on Intubation or Mortality Among Patients With Acute Hypoxemic Respiratory Failure and COVID-19: The RECOVERY-RS Randomised Clinical Trial. JAMA. 2022; 327(6): 546-558 doi:10.1001/ jama.2022.0028 PMID: 35072713; PMCID: PMC8787685.

Think back to the early days of the COVID-19 pandemic, the scramble to nd out information, webinars with colleagues treating patients to glean treatment strategies, the uncertainty of what we were facing. Luckily we are now in a much better place, in no small part thanks to some incredible pieces of research that gave us treatment options and of course, the amazing speed at which safe and effective vaccines were produced and rolled out.

But...what about our management of acute hypoxic respiratory failure in patients with COVID-19.

There has been increasing and widespread use of continuous positive airway pressure (CPAP) and high- ow nasal oxygenation (HFNO), but there have been con icting results regarding their ef cacy.

The RECOVERY-RS trial is a randomised, prospective, multi-centre trial conducted at 75 hospitals across the UK and was designed to determine whether either CPAP or HFNO, compared with conventional oxygen therapy, improves clinical outcomes in hospitalised patients with COVID-19 related acute hypoxaemic respiratory failure.

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The conclusion - “among patients with acute hypoxaemic respiratory failure due to COVID-19 an initial strategy of CPAP signi cantly reduced the risk of tracheal intubation or mortality compared with conventional oxygen therapy, but there was no signi cant difference between an initial strategy of HFNO compared with conventional oxygen therapy.”

So does this study change your practice? Will you no longer use HFNO in this patient group, instead reaching for the CPAP mask rst? Or is it a bit more complicated than that? This is a brilliant paper with some very interesting points to lead a discussion with, for example the study did not meet its pre-planned sample size due to a fall in cases and recruitment ending.

Whilst we all hope that the worst days of the pandemic are behind us, studies like this remind us of the incredible work done to date - rapidly improving the care our patients received and will receive thanks to studies such as this, RECOVERY and REMAP-CAP. That is truly something to be celebrated.

Comparing the rst-attempt tracheal intubation success of the hyperangulated McGrath® X-blade vs the Macintosh-type CMAC videolaryngoscope in patients with cervical immobilization: a twocentre randomised control trial. ✦

Zhang J, Tan LZ, Toh, H, Foo CW, Wijeratne S, Hu H and Seet E. Comparing the rst-attempt tracheal intubation success of the hyperangulated McGrath® X-blade vs the Macintosh-type CMAC videolaryngoscope in patients with cervical immobilization: a two-centre randomised control trial. AJ Clin Monit Comput. 2022; 36 (4) : 1139 - 1145. doi: 10.1007/ s10877-021-00746-5 Epub 2021 Aug 4. PMID: 34347225.

Patients with cervical spine precautions present a challenging airway even in the absence of other factors that increase the risk of a dif cult airway. Whilst the debate around the use of manual in-line stabilisation during airway management in this patient group carries on, evaluation of different devices continues. What type of blade should we be reaching for when managing such patients, a hyperangulated blade or a MAC blade?

This two centre randomised control trial compared blades from two brands of video laryngoscopes, the hyperangulated McGrath X-blade and the Macintosh-type CMAC blade in patients undergoing anaesthesia who had manual inline stabilisation undertaken with the primary outcome measure being rst-attempt tracheal intubation success.

The authors conclusion - “our study did not demonstrate a signi cant difference in ef cacy between the McGrath X-blade and the CMAC video laryngoscope”. But is that the full story?

Delve into this paper and have a look at the exclusion criteria - does this re ect the type of patients we see when confronted with a patient requiring cervical spine immobilisation?

Interestingly the study was underpowered to detect a difference between the two blade types, this is a perfect opportunity in a journal club to refresh our knowledge on power calculations and why these matter when designing a study.

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AIRWAY MANAGEMENT IN MAJOR TRAUMA, AN AUSTRALIAN PERSPECTIVE | Peter Forrest | Christopher Groombridge | Simon Hendel | Pierre Bradley

Victoria is the second most populous state in

of severely injured patients (Injury Severity

Australia and geographically is a similar size

Score (ISS) > 12) to one of three major trauma

landmass to the island of Great Britain. There

centres (2 adult and 1 paediatric). The system

has been an integrated State Trauma System

incorporates regional (Level-2) trauma

in place since 2000.1 This system prioritises

centres, and a system for primary retrieval

the early identi cation, treatment, and transfer

from point-of-injury to a major trauma centre,

Fig 1: Structure of trauma services in Victoria, Australia.1

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Fig 2: Top 10 causes of Injury for all trauma admissions at The Alfred in 2021.3

and secondary retrieval from lower to higher

care ambulance (MICA) paramedics).

levels of in-hospital care. This is a hub and

Victoria’s Helicopter Emergency Medical

spoke model of trauma retrieval which is

Service is staffed by MICA paramedics with

appropriate to the geography and

advanced practice guidelines. Unlike much of

demography of Victoria. Comparable

the UK and other Australian states, there are

approaches are employed throughout

no joint physician-paramedic prehospital

Australia, to prioritise transfer to de nitive

teams.

care.2

In-hospital airway management in major

The Alfred Hospital is one of the adult major trauma centres and state referral centre for major burns and Extra Corporeal Life Support.

In 2021, the service had 9915 trauma admissions of which 14% had an ISS > 12.3 As with most jurisdictions outside the USA, blunt trauma represents greater than ninetyve percent of trauma presentations in Victoria, with the majority occurring outside of metropolitan Melbourne.4 Airway management begins at the scene by paramedics of varying skillsets (community volunteers, quali ed ambulance paramedics, and mobile intensive

trauma patients The NAP4 study has highlighted the dangers of emergent airway management in the nontheatre environment, especially in the out of hours period.5 The Alfred has had a specialist anaesthetist on site 24-7 (known as the consultant in charge; CIC) for over 20 years and has moved towards a continuous specialist emergency physician presence since the advent of COVID-19. Trauma call alerts are received by the full trauma team, with anaesthesia medical provider

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involvement 24-hours a day. Between 0730

investigations (along with ensuring staff

and 2300, the CIC receives the alert and

safety) is common.

designates appropriate personnel to the trauma bay. Outside these times, the initial alert is received by anaesthesia registrars and response is escalated to the CIC as required.

This system ensures early, senior anaesthesia presence for major trauma (and burns), and serves as an early warning for operating suite readiness.

In the emergency department, the rst attempt laryngoscopist is usually an emergency medicine trainee, under the supervision of a Specialist Emergency Physician or Specialist Anaesthetist. There is an established education program, associated protocols, and a tailored checklist for these patients, with videolaryngoscopy using Karl-Stortz C-MAC

Airway management in trauma falls into 3

and a bougie being the preferred

broad categories: non airway trauma, airway

technique.6

injury (including burns), and intubation to

anaesthesia is standardised (using pre-drawn

facilitate de nitive care. Irrespective of reason,

syringes of ketamine, fentanyl and

airway management is the primary

rocuronium). This has previously caused

responsibility of the CIC in conjunction with

controversy between anaesthesia and the

the trauma team leader. The role of primary

emergency department, but it is largely

laryngoscopist may be delegated to trainees

accepted as a safer combination of drugs in

depending on urgency, perceived complexity,

most patients allowing for a range of

staff experience, or other competing

anaesthesia skills. The induction drug

resuscitation priorities. The Alfred is a

combination can be tailored to patient need

quaternary trauma teaching hospital, so

and should be discussed within the team,

ensuring safe, supervised opportunities for

ideally prior to patient arrival.6

developing advanced airway skills in trainees is an important health-service role.

1. Emergent management of the nontraumatised airway

2. The injured airway Complex maxillofacial and trachea-bronchial injury is rarely the primary indication for airway

Emergent endotracheal intubation for non-

attention to the airway assessment allows for a

airway trauma in the emergency department is

careful collaborative decision-making

most commonly due to head injury.6 Drug-

approach, ensuring safe airway management

affected individuals are overrepresented in

in the appropriate location with correct

trauma presentations and within Victoria, 13%

staff.9,10

centre tested positive for an illicit substance.

Of these patients, 77% tested positive to methamphetamines – a re ection of Australia’s challenges in addressing methamphetamine use in the community. 7,8 Induction of anaesthesia and intubation to achieve situational control and facilitate on-going

Developing an airway and oxygenation strategy is essential in managing trauma patients with these injuries. It is in this group that the use of video-laryngoscopy may prove dif cult, with the presence of blood in the airway potentially impairing visualisation of the glottis. MacIntosh geometry video-

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As far as possible, induction of

management. When it occurs, speci c

of individuals presenting to a major trauma

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laryngoscopes, which also allow direct

have been identi ed (Table 1), although it is

laryngoscopy (such as CMAC / Glidescope

yet to undergo prospective validation.13

Direct view), are preferred. I-Gels

3. Airway management for de nitive care

(Intersurgical, UK) have recently been introduced as the supra-glottic airway of choice in the dif cult airway trolley and are easily accessible across all locations where advanced airway management occurs.11 Equipment is available for both needle and surgical cricothyroidotomy on the dif cult airway trolley.12 However, in the non-fasted non-elective patient, surgical cricothyroidotomy is the rescue technique of choice, if a primary front of neck approach

In patients requiring airway control for de nitive care, there is time to plan, prepare, and then perform. While airway management for de nitive care should be timely and made in the context of other treatment priorities, there is reduced time-pressure than in the emergency airway. In planning airway management for de nitive care, anaesthetists should consider the surgical access required and whether the plan is suitable for ongoing intensive care, or whether a post-operative

was not employed.

plan (e.g. tube exchange) may be required.

Patients with signi cant airway burns fall into

As with all effectively executed plans,

this category. Early identi cation of airway

multidisciplinary communication is key to

involvement and intubation is required to

success.

prevent a very dif cult situation developing, however predicting inhalation injuries can be

Human factors in airway management

dif cult. A predictive model has been

The importance of human factors in airway

developed at The Alfred based on 1148

management is not new and in the

presentations over a 7-year period to the

management of major trauma, clear

Victorian Adult Burns Service. Seven variables

communication is a key precondition for

Table 1: Predictors of inhalation injury in Burns Patient.13

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success. The trauma service at the Alfred is

fellow alongside emergency medicine and

not run by the general surgical team of the

surgery fellows). Alternatively, a full year in

day (as in many other centres). Instead,

anaesthesia is also possible. Interested

‘trauma’ is its own multidisciplinary admitting

trainees can contact S.Hendel@Alfred.org.au

unit and is staffed by specialist trauma

for further information.

consultants, junior medical staff, and crucially

May each year, for employment from the

supported by expert nursing and allied health

following February. August commencement is

professionals. Trauma consultants are

available by mutual negotiation.

recruited from a range of specialties including s u r g e r y, e m e r g e n c y m e d i c i n e , a n d

Applications open in

Conclusions

anaesthesia (although intensive care

Airway management in trauma can provide

specialists are eligible for recruitment, none

signi cant challenges to the trauma team,

are currently employed as trauma

both in the decision to intubate and the

consultants). This team approach is invaluable

complexity and timing of the intubation itself.

i n en a bling smoot h inter-discipli n a r y

Despite these challenges, a multi-disciplinary

prioritization and decision-making. It also

approach within a major trauma service can

centralizes a breadth of expertise across

foster a proactive approach in safely

surgery and critical care (in both military and

managing severely injured patients while

civilian settings) under the one banner.

simultaneously providing training

The establishment of an ongoing airway audit and teaching program in our emergency

opportunities for trainees from multiple craftgroups.

department has contributed to consistent

Dr Peter Forrest, Anaesthesia Registrar, The

high-quality care, especially with the rotation

Alfred, Melbourne, Australia

of anaesthesia and emergency registrars

Dr Christopher Groombridge, Emergency

every 6 months. The introduction of the

Medicine Physician and Trauma Consultant;

program found a signi cant improvement in

Emergency Department Airway Lead, The

rst attempt success rate (95% vs 89%) without a change in adverse

events.6

The

Alfred has developed a trauma-anaesthesia clinical fellowship and is coordinated by the two specialist anaesthetists who are also employed as trauma consultants.

The

fellowship focuses on individual and collective

Alfred Dr Simon Hendel, Anaesthesiologist and Tr a u m a C o n s u l t a n t ; H e a d o f Tr a u m a Anaesthesia, The Alfred; Clinical Research Fellow, National Trauma Research Institute, Australia.

trauma-team training, clinical exposure across

Associate Professor Pierre Bradley, Adjunct

the patient journey (from point of injury to

Clinical Associate Professor, Monash

hospital discharge), quality improvement, and

University, Victoria; Anaesthesiologist, The

clinical research.

Alfred, Melbourne, Australia

Opportunities exist for senior trainees to spend six months of a twelve-month

Link to references

fellowship in the trauma service (as a trauma

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NEW PATIENT INFORMATION FOR AWAKE TRACHEAL INTUBATION: JUNE 2022 | Kate Rivett | DAS have updated their patient

procedure with reference to

information for Awake Tracheal

patient experience. Clear

Intubation (ATI) for patients. The

explanations are given for terms

June 2022 version is now

such as intubation and awake

available here.

intubation, together with brief descriptions of

A recent patient panel lead by

exible

bronchoscopes and video

DAS highlighted that patients

laryngoscopes and how their

would generally prefer to have

usage might differ.

access to detailed information

There is a

constant message that the

about anaesthetic or airway

anaesthetist and the clinical team

management topics well in

are available to offer advice and

advance of the day of surgery. If the need for ATI is identi ed at preassessment then this is the ideal time for the patient to be made aware of the extensive

answer questions, in addition to their involvement in the technical aspects of the procedure.

patient materials that are available. The ATI

Whilst signposting to the relevant section of

information helps patients to understand the

the DAS website might be the preferred

nature of the procedure and how this might

option for some patient groups, consideration

differ from previous anaesthetic experiences.

should also be given to those members of the

The provision of any patient information in an emergency setting will always be balanced against the acuity of the patient, and the likelihood of their ability to comprehend any aspects of their emergency care. For those patients however who are allocated to an emergency list (CEPOD) there may well be an opportunity to discuss the preferred anaesthetic technique and provide accurate and timely information as part of their perioperative care.

public who prefer to have a hard copy.

Provision of hard copy ensures that the patient does have the correct DAS version (rather than possibly accessing information from an internet source where clinical content is not necessarily accurate or approved).

Access to the internet within Trusts is variable (at best) and hard copy allows the patient adequate time to re-read, re ect and possibly question the content before undergoing any procedure.

The June 2022 version is

currently only available in English and Welsh.

The aim of the new ATI patient guidance is to

DAS is currently investigating how it might be

provide a brief explanation of the process,

possible to offer a wider variety of language

rationale, equipment and risks whilst

options.

providing a basic knowledge of the

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The concept of ATI is familiar to airway

For those patients who have been identi ed

specialists and anaesthetists, however this

as having a dif cult airway necessitating an

level of knowledge is not representative of the

ATI, the patient information also provides a

wider population. Whilst the Covid pandemic

link to the DAS Airway Alert Card Project.

might have heightened awareness of the

Whilst clinical involvement is a requirement to

need for mechanical ventilation, the

establish a patient on the DAS database, the

associated airway management would not

patient information appertaining to this

generally be understood as integral to this

project supports the initiative and clearly

process. The key aspects of general

identi es the patient bene ts.

anaesthesia remain a mystery to many people with the speci c concepts of any intubation technique or associated airway management not even being considered as part of having a general anaesthetic; this level of comprehension should be considered when outlining the need for ATI. The provision

In addition to the new ATI patient information the DAS website now has a link to a joint DAS/RCoA lea et ‘Your airway and breathing during anaesthesia’ (February 2020).

This

patient information, produced with the RCoA, is widely translated.

of patient information is designed to support the consultation for both the patient and the

Kate Rivett, DAS patient representative

clinician.

DAS continues to work to improve the patient information available. An infographic, with a glossary on ATI is currently in the review process and we hope to be able to publish this early in the Autumn.

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DIFFICULT AIRWAY DATABASE - AN UPDATE | Achuthan Sajayan | DAS Dif cult airway database is continuing

If your hospital is not yet part of this project

its expansion across the country and several

and you are interested in taking the lead

national organisations have con rmed their

role locally, please do get in touch with us

of cial support to the project in the last few

via dad@das.uk.com. If you work in a

months. The following is the list of

hospital which is already a part of the

organisations supporting us:

project, please encourage your colleagues

✦

Society for Obesity and Bariatric Anaesthesia (SOBA)

to submit the data promptly and let us know if you have any feedback about the project or the process of submission.

✦

Association of Anaesthetists (AoA)

✦

Obstetric Anaesthetists Association (OAA)

✦

Royal College of Anaesthetists (RCoA)

✦

Safe Anaesthesia Liaison Group (SALG)

✦

Association for Perioperative Practice (AfPP)

✦

College of Operating Department Practitioners (CODP)

✦

Society for Education in Anaesthesia (SEAUK)

✦

UK Society for Computing and Technology in Anaesthesia (SCATA-UK)

✦

Intensive Care Society (ICS)

DAS Airway Alert Card and Difficult Airway Database​ -​ How to join the project?

----------------------------------------------------Check if your hospital is already on the project https://das.uk.com/content/dad_sites If not, please follow the steps below

Here is the comparison of current gures with those from September 2021: Sept 21

Current Status

150 Hospital sites

190

820+ submissions

1200+

page and the list of Trusts currently taking

1935 Access logins

2500+

part in the project. Other project related

Some useful links are: DAS Database main

The analysis of the data collected over the rst

ve years has very recently been

published in Anaesthesia! Here's the link

documents can be found here.

Dr Achuthan Sajayan

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dad@das.uk.com

Co-Lead, DAS Dif cult Airway Database Contents

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How to submit a case to the DAS Database? https://das.uk.com/dad Consent Download the patient information and consent form from the DAS website https://das.uk.com/aac/con sent_form Discuss with the patient and obtain the consent.

Please make sure the patient has recovered fully from the effects of anaesthesia. Recovery room is not a recommended place for consenting.

Give one copy to the patient and keep one in the records

Data submission If you are not a DAS member, you need to register with the database before submitting data.

Registration is free and only takes few minutes.

Please follow this link https://das.uk.com/das_user/ acaregister

Summary document Once the data is submitted, there will be an option to print out the summary of the event.

Please print two copies, give one to the patient and keep the other in the patient records.

There will also be an option to print out a letter to the GP. This can either be sent directly to the GP or give it to the patient with instructions to hand over to their GP.

If you are a trainee or specialty doctor, please discuss with your supervising consultant before submitting the data and provide their name

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WORLD AIRWAY MANAGEMENT MEETING | Ellen O’Sullivan |

Following on from the success of WAMM1, held in Dublin in 2015, and WAMM 2 in Amsterdam in 2019 we plan to run a WAMM 3. Dates and venues are presently being discussed.

WATCH THIS SPACE! FURTHER ANNOUNCEMENTS COMING SOON!

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PROPOSALS TO HOST OUR ANNUAL SCIENTIFIC MEETING IN 2024!!

We are delighted to welcome proposals from those interested in hosting the DAS ASM in 2024. Proposals should contain information on the proposed venue(s) and costs, hotel accommodation nearby and transport links as a minimum.

Key Dates: Submission of Proposals Window Opens: 1st July 2022 Deadline for Submissions: Midnight, 16th September 2022 Shortlisted proposals will be invited for presentation in October 2022 DAS expect all those considering a bid to contact us and discuss what is involved in hosting prior to submission.

Email: secretary@das.uk.com for more details.

Submissions should be emailed to the DAS Secretariat at: das@anaesthetist.org @dasairway @dastrainees #DASeducation

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PERIOPERATIVE MEDICINE: RISK ASSESSMENT | References 1/2 |

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Pearse RM, Holt PJE, Grocott MPW. Managing perioperative risk in patients undergoing elective non-cardiac

surgery. BMJ. 2011 Oct 5; 343:d5759.

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Moonesinghe SM, Mythen MG, Das P, Rowan KM, Grocott MPW. Risk strati cation tools for predicting

morbidity and mortality in adult patients undergoing major surgery. Anesthesiology. 2013 Oct; 119(4):959–81.

3.

Khuri SF, Henderson WG, DePalma RG, Mosca C, Healey NA, Kumbhani DJ, et al. Determinants of long-term

survival after major surgery and the adverse effect of postoperative complications. Ann Surg. 2005 Sept; 242(3):326-343.

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Findlay GP, Goodwin APL, Protopapa K, Smith NCE, Mason M. National Con dential Enquiry into Peri-

Operative Outcomes and Deaths. Knowing the Risk. A review of peri-operative care of surgical patients. 2011.

Available from: https://www.ncepod.org.uk 5.

Pearse RM, Harrison DA, James P, Watson D, Hinds C, Rhodes, A, et al. Identi cation and characterisation of

the high-risk surgical population in the United Kingdom. Critical Care. 2006 June 2; 10:R81.

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Royal College of Surgeons. The high-risk general surgical patient: raising the standard. 2018. Available from:

https://www.rcseng.ac.uk 7.

Levett DZH, Jack S, Swart M, Carlisle J, Wilson J, Snowden C, et al. Perioperative cardiopulmonary exercise

testing (CPET): consensus clinical guidelines on indications, organization, conduct, and physiological interpretation.

British Journal of Anaesthesia. 2018 Nov 24; 120(3): 484-500.

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Duceppe E, Parlow J, MacDonald P, Lyons K, McMullen M, Srinathan S, et al. Canadian Cardiovascular

Society guidelines on perioperative cardiac risk assessment and management for patients who undergo noncardiac surgery. Can J Cardiol. 2017; 33:17-32.

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De Hert S, Staender S, Fritsch G, Hinkelbein J, Afshari A, Bettelli G, et al. Pre-operative evaluation of adults

undergoing noncardiac surgery: Updated guideline from the European Society of Anaesthesiology. Eur J Anaesthesiol.

2018; 35:407–465.

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Oliver CM, Walker E, Giannaris S, Grocott MPW, Moonesinghe SM. Risk assessment tools validated for

patients undergoing emergency laparotomy: a systematic review. Br J Anaesth. 2015 Nov 3; 115(6): 49–60.

11.

Lee TH, Marcantonio ER, Mangione CM, Thomas EJ, Polanczyk CA, Cook EF, et al. Derivation and

prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation 1999; 100:1043–9.

12.

Stones J, Yates D. Clinical risk assessment tools in anaesthesia. BJA Educ. 2019 19(2):47-53.

13.

Nashef SAM, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J

Cardiothorac Surg. 2012; 41: 734–745 14.

Maxwell MJ, Moran CG, Moppett IK. Development and validation of a preoperative scoring system to predict

30 day mortality in patients undergoing hip fracture surgery. Br J Anaesth. 2008 Aug 21; 101(4):511–17.

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PERIOPERATIVE MEDICINE: RISK ASSESSMENT | References 2/2 | 15.

Eugene N, Oliver CM, Bassett MG, Poulton TE, Kuryba A, Johnston C, et al. Development and internal

validation of a novel risk adjustment model for adult patients undergoing emergency laparotomy surgery: the National Emergency Laparotomy Audit risk model. Br J Anaesth 2018;121:739–48.

16.

Canet J, Gallart L, Gomar C, Paluzie G, Valles J, Castillo J, et al. Prediction of postoperative pulmonary

complications in a population-based surgical cohort. Anesthesiology. 2010 Dec; 113:1338–1350.

17.

Park S, Cho H, Park S, Lee S, Kim K, Yoon HJ, et al. Simple Postoperative AKI Risk (SPARK) Classi cation

before Noncardiac Surgery: A Prediction Index Development Study with External Validation. J Am Soc Nephrol. 2019 Jan; 30 (1):170-181.

18.

El-Boghdadly K, Lockwood S, Crawshaw A, McNally S, Summerton D, Mercer N et al. Preoperative

assessment and optimisation for adult surgery, including consideration of COVID-19 and its implications. 2021.

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Prytherch DR, Whiteley MS, Higgins B, Weaver PC, Prout WG, Powell SJ. POSSUM and Portsmouth POSSUM

for predicting mortality. Physiological and operative severity score for the enumeration of mortality and morbidity. Br J Surg. 1998; 85(9):1217–1220.

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Protopapa KL, Simpson JC, Smith NCE, Moonesinghe SR. Development and validation of the Surgical

Outcome Risk Tool (SORT). Br J Surg. 2014; 101:1774-1783.

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Bilimoria KY, Liu Y, Paruch JL, Zhou L, Kmiecik TE, Ko CY, et al. Development and evaluation of the universal

ACS NSQIP surgical risk calculator: a decision aid and informed consent tool for patients and surgeons. Am Coll Surg.

2013 Nov; 217(5):833-842.

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National Institute for Health and Care Excellence (NICE). Perioperative care in adults: Evidence review for

perioperative risk strati cation tools. NICE. 2020 Aug 19. Available from: https://www.nice.org.uk 23.

American College of Cardiology (ACC)/American Heart Association (AHA) Task Force. 2014 ACC/AHA

guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery.

Circulation. 2014;130:e278-e333.

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ESA Guidelines on non-cardiac surgery: cardiovascular assessment and management. Eur Heart J. 2014;35:2383– 2431.

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General Medical Council (GMC). Decision making and consent. 2020 September 30. Available from:

www.gmc-uk.org 26.

Royal College of Anaesthetists. Common events and risks in anaesthesia. 2019 September. Available from:

https://rcoa.ac.uk

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PERIOPERATIVE MEDICINE: CPET | References 1/1 |

1.

Prinz JP. Elisee Bouny. The inventor of the bicycle ergometer. In: Kurt Tittel, Karl-Hans Arndt, Wildor Hollmann

(eds.): Sports medicine. Yesterday Today Tomorrow. Report from the anniversary symposium of the German Association of Sports Physicians, Oberhof from September 25th to 27th, 1992 2.

Lalabekyan BB, et al. Cardiopulmonary exercise testing and cardiopulmonary morbidity in patients

undergoing major head and neck surgery. J Oral Maxillofac Surg. 2021 Apr;59(3):297-302 3.

Bedin DCC et al . Is it possible to perform cardiopulmonary exercise test in laryngectomized patients?

European Respiratory Journal 2018 52: PA2485 4.

American Thoracic Society. ATS/ACCP statement on cardiopulmonary exercise testing. Am J Respir Crit Care

Med 2003; 167: 211e77

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PERIOPERATIVE MEDICINE: FRAILTY | References 1/3 | 1.

Head and neck cancers statistics | Cancer Research UK

2.

Frailty in the older surgical patient: a review - PubMed (nih.gov)- Partridge et al. – 2012

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PERIOPERATIVE MEDICINE: FRAILTY | References 2/3 | 4AsT: 19.

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PERIOPERATIVE MEDICINE: FRAILTY | References 3/3 |

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AIRWAY MANAGEMENT IN MAJOR TRAUMA: AN AUSTRALIAN PERSPECTIVE | References | 1. Atkin in C, Freedman I, Rosenfeld JV, Fitzgerald M, Kossmann T. The evolution of an integrated State Trauma System in Victoria, Australia. Injury. 2005 Nov;36(11):1277-87. doi: 10.1016/j.injury.2005.05.011. PMID: 16214472 2. Cameron PA, Fitzgerald MC, Curtis K, McKie E, Gabbe B, Earnest A, Christey G, Clarke C, Crozier J, Dinh M, Ellis DY, Howard T, Joseph AP, McDermott K, Matthew J, Ogilvie R, Pollard C, Rao S, Reade M, Rushworth N, Zalstein S; Australian Trauma Quality Improvement Program (AusTQIP) collaboration. Over view of major traumatic injury in Australia--Implications for trauma system design. Injury. 2020 Jan;51(1):114-121. doi: 10.1016/j.injury.2019.09.036. Epub 2019 Oct 3. PMID: 31607442.

3. Fitzgerald M, The Alfred Trauma Audit: 1st July 2020-30th June 2021 [PowerPoint presentation]. The Alfred Hospital, Melbourne. Presented 21 Nov 2021 4. Victorian State Trauma Outcomes Registry and Monitoring Group. Victorian State Trauma Registry Annual Report 2019– 2020. [Online]. Available from: https://www.monash.edu/__data/assets/pdf_ le/0008/2706047/VSTR-Annual-Report-2019-20WEB_FINAL.pdf [Accessed 17 July 2022].

5. Cook TM, Woodall N, Harper J, Benger J; Fourth National Audit Project. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Dif cult Airway Society. Part 2: intensive care and emergency departments. Br J Anaesth. 2011 May;106(5):632-42. doi: 10.1093/bja/aer059. Epub 2011 Mar 29. PMID: 21447489.

6. Groombridge C, Maini A, Olaussen A, Kim Y, Fitzgerald M, Mitra B, Smit V. Impact of a targeted bundle of audit with tailored education and an intubation checklist to improve airway management in the emergency department: an integrated time series analysis. Emerg Med J. 2020 Sep;37(9):576-580. doi: 10.1136/emermed-2019-208935. Epub 2020 Jun 17. PMID: 32554746.

7. Peacock A, Leung J, Larney S, Colledge S, Hickman M, Rehm J, Giovino GA, West R, Hall W, Grif ths P, Ali R, Gowing L, Marsden J, Ferrari AJ, Grebely J, Farrell M, Degenhardt L. Global statistics on alcohol, tobacco and illicit drug use: 2017 status report. Addiction. 2018 Oct;113(10):1905-1926. doi: 10.1111/add.14234. Epub 2018 Jun 4. PMID: 29749059.

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AIRWAY TRAINING OF DREAMS, 1ST PRIZE CREATIVE WRITING | References | 1.T. M. Cook, N. Woodall, C. Frerk, on behalf of the Fourth National Audit Project, Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Dif cult Airway Society. Part 1: Anaesthesia. British Journal of Anaesthesia. 2011;106(5):617–631.

2.Dashe & Thomson. 35 Inspiring Quotes about learning. 2022 Available: https://www.dashe.com/blog/motivation/ inspiring-learning-quotes/ [Accessed 14/04/22] 3.Marshall SD, Chrimes N. Time for a breath of fresh air: Rethinking training in airway management. Anaesthesia.

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4.Al-Elq, A. Simulation-based medical teaching and learning. Journal Of Family And Community Medicine.2010;17(1), 35.

5.Bruce R, McLeod A, Smith G. A Survey of UK anaesthetic trainee attitudes towards simulator-based training experience. Royal College of Anaesthetists Bulletin 2005;34:1722-3.

6.Royal College of Anaesthetists (RCOA). Simulation Strategy 2018-2023. (2018) Available: https://www.rcoa.ac.uk/ sites/default/ les/documents/2019-07/Simulation-Strategy-FINAL.pdf [Accessed 13/04/2022].

7.Frerk C, Mitchell VS, McNarry AF, et al. Dif cult Airway Society 2015 guidelines for management of unanticipated dif cult intubation in adults. British Journal of Anaesthesia 2015;115: 827–48.

8.Howard‐Quijano KJ, Huang YM, Matevosian R, Kaplan MB, Steadman RH. Video‐assisted instruction improves the success rate for tracheal intubation by novices. British Journal of Anaesthesia. 2008;101: 568–72, e1.

9.McGaghie WC, Issenberg SB, Barsuk JH, Wayne DB. A critical review of simulation‐based mastery learning with translational outcomes. Medical Education 2014;48: 375–85.

10.Ahmad I, El-Boghdadly K, Bhagrath R et al. Dif cult Airway Society guidelines for awake tracheal intubation (ATI) in adults. Anaesthesia, 2020;75: 509-528.

11.Marshall SD. Use of cognitive aids during emergencies in anesthesia: A systematic review. Anesthesia and Analgesia 2013;117: 1162–71.

12.Lindkær Jensen, NH, Cook, TM and Kelly, FE. A national survey of practical airway training in UK anaesthetic departments. Time for a national policy?. Anaesthesia. 2016; 71:1273-1279.

13.Marshall SD, Chrimes N. Time for a breath of fresh air: Rethinking training in airway management. Anaesthesia.

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15.Looseley A, Wainwright E, Cook TM, et al. Stress, burnout, depression and work satisfaction among UK anaesthetic trainees; a quantitative analysis of the Satisfaction and Wellbeing in Anaesthetic Training study. Anaesthesia.

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16.Sauerteig S, Wijesuriya J, Tuck M, Barham-Brown H. Doctors’ health and wellbeing: at the heart of the NHS’s mission or still a secondary consideration? Intl Rev Psychiatry. 2019;31(7-8):548-554.

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