Scottish Airway Group Annual Meeting Report 2016
Dr Andrew J Dalton, ST7 Anaesthesia, Tayside
The sixth annual Scottish Airway Group meeting took place at the Royal Concert Hall, Glasgow on Friday 4th March 2016. The meeting was very well attended, with delegates from throughout Scotland amongst the audience. The meeting this year was organised by Dr Craig Urquhart and Dr Kevin Fitzpatrick from Glasgow.
The first talk was entitled “Tongue, Teeth and the Airway” by Dr Brian Stickle, who is a Consultant Anaesthetist in Aberdeen. He reviewed the anatomy and function of the oropharyngeal cavity, whilst emphasising the difference between airway function and patency in an awake patient versus that after anaesthesia/paralysis. This should always be a consideration when planning an airway strategy. He reviewed potential problems with the tongue; ranging from increased size (e.g. after trauma, flap surgery or due to angioedema), loss of function (including a wooden, fixed tongue post radiotherapy) to bleeding (often due to tumour or trauma). During this he emphasised that assessment is paramount, and we should have a low threshold for nasendoscopy assessment; and, if in doubt, consider performing an awake fibreoptic intubation as most tongue problems will worsen with loss of consciousness. He then reviewed the management of abscesses, stating that warning signs are voice changes, dysphasia, dysphonia, dyspnoea and stridor. The key parts of this assessment are tongue protrusion and mouth opening: if you can open your mouth sufficiently for laryngoscope access, and protrude your tonguethen it will likely be safe to perform a standard general anaesthetic. However, if these features are absent then an awake fibreoptic intubation should be performed.
This was followed by Dr Ben Ulyatt, a Consultant Anaesthetist at Ninewells Hospital, who spoke about “Laryngeal issues: Airway obstruction”. After reviewing the potential causes of airway obstruction, he then focused on how to adapt an airway management strategy, with the focus being that even the best laid plans can fail! He did this with the aid of a very interesting case report of a patient he had recently anaesthetised, that the rest of the audience were pleased had not come during their own on-call! During the discussion around AFOI, awake tracheostomy, pre-emptive cannula cricothyroidotomy, he showed how in his case each had been considered/performed and each had failed, demonstrating that “no plan is always successful, and experience … determines outcome when the initial strategy is unsuccessful” as stated by NAP4. He viewed non-technical skills to be the key to management and a successful outcome, with the importance of planning, prioritising, teamwork, anticipation, and successful communication the key to achieve this.
The morning session was concluded by Dr Malcolm Watson, a Consultant Anaesthetist from Glasgow with an interest in Regional anaesthesia. His talk encompassed “Regional Anaesthesia and Ultrasound of the Airway”. An initial discussion of performing a superficial cervical plexus block was then followed with examples of other ultrasound guided airway blocks -however, the caveat was that these do not seem to be any more successful techniques for airway topicalisation than using a mucosal atomisation device (MAD) which is less invasive! He then discussed ultrasound of the airway, with some very clear ultrasound images demonstrating what information can be obtained and how this can guide the placement of tracheostomies and cricothyroidotomies when in expert hands. However, in the emergency situation of a ‘can’t intubate, can’t oxygenate’, there was debate as to how useful it would be given the time factor required to perform it in an already time pressurised, stressful environment.
After coffee, we recommenced with the trainee oral presentations. Dr Rachel Harvey opened by giving an update on her SAG sponsored project entitled “Distraction cards improve the number of successful steps undertaken during simulated ‘can’t intubate/oxygenate’ scenarios”. Her project posed the question of whether prompt cards could help the performance of complex emergency tasks, and the findings have been very positive, with the randomised ‘no card’ group performing 10 critical steps from 17, compared with the card group performing 16 or 17 of the 17 identified critical steps for cannula cricothyroidotomy, which had statistical significance following T-test analysis. She plans to continue the project by restudying it for surgical cricothyroidotomy after the revised DAS guidelines. Competing for the oral prize were Dr Karen Pearson, Dr Dima Nassif and Dr Jennifer Service. Dr Pearson spoke about her education project regarding the Airway Rescue Trolleys in Ninewells Hospital, and that after the identification of poor knowledge of both trolley contents and location, she undertook teaching of both medical and nursing staff, and then reaudited showing a marked improvement in knowledge and understanding of the concept. Dr Nassif spoke about “Sugammadex -4 years of clinical experience” in NHS Tayside and how the Sugammadex use has increased each year, with residual neuromuscular blockage remaining a worryingly high reason for requiring Sugammadex. She spoke about how increased vigilance to monitoring the NMB with quantitative monitoring devices may reduce this incidence and therefore potentially reduce the requirements for Sugammadex rescue. Dr Service concluded the presentations with her talk on “High flow nasal cannulae for outpatient bronchoscopy” in St Johns Hospital, Livingston. She demonstrated that after an initial trial period the bronchoscopy service has now switched to undertaking their sedation lists using high flow nasal cannulae as the method of oxygenation based on less desaturation episodes and higher satisfaction ratings from both the anaesthetists and bronchoscopists. All the talks were very well presented and received, and after a close vote the judges awarded the first prize to Dr Pearson.
Dr Alistair May concluded the morning with a very interesting talk entitled “Let’s think how we train”. He spoke about changing the focus of teaching/learning from the traditional apprenticeship model to a more modern approach of mastery learning, whereby tasks are broken down into lots of small steps to develop the overall skill. He highlighted several studies showing that mastery learning helps learn tasks quicker and produce better performance, with significant retention of the skills even when retested after a prolonged time period. He described his experience of implementing this teaching in his unit for new starts learning airway skills with very promising results from both the trainees and the trainers (including some sceptical members!). His talk challenged all trainers present to ensure they make the most of opportunities to teach and how they go about maximising the learning experience for trainees. The lunch break followed, which allowed the opportunity to review the excellent poster presentations and visit the trade displays.
Dr Anil Patel, a Consultant at the Royal National Throat Nose and Ear Hospital, current DAS president and much respected international speaker, followed with two talks; firstly “DAS updated guidelines”. He spoke about the development of the guidelines, and the main changes from the previous 2004 version. There is no longer a separation between unexpected difficult intubation in a ‘routine’ induction vs rapid sequence; instead these have been combined into a single algorithm. Videolaryngoscopy has been included to reflect the changing practice across the UK, but no specific type of video scope has been recommended as there is insufficient evidence to do so. After 3 laryngoscopy attempts, the focus is now much more on oxygenation via a second generation SAD and wake up from here as the primary mindset, rather than the more focused secondary intubation plan of the previous guidelines. The other main shifts are regarding paralysis and front of neck access. The theme is that “nobody should get to can’t intubate/oxygenate without being fully paralysed”. Therefore, after failed intubation, SAD and face mask ventilation, ensure paralysis for one final attempt at face mask ventilation prior to undertaken emergency cricothyroidotomy. Regarding emergency cricothyroidotomy, surgical ‘scalpal, bougie, tube’ is now the recommended technique. It is recognised that there is thankfully limited evidence to draw on for this, but Dr Patel stated there “is not enough evidence to choose any particular technique, but enough evidence to choose one!” which has led to the shift in the guidance. Dr Patel then spoke about his landmark research and publication regarding THRIVE (transnasal, humidified, rapid insufflation ventilatory exchange) oxygenation. He discussed the process of undertaking THRIVE and the THRIVE triangle of ‘CPAP, apnoeic ventilation and apnoeic oxygenation’. THRIVE has been shown to be suitable for pre-oxygenation (with no additional face mask required), and at maintaining oxygenation even after the onset of apnoea as long as a patent airway is maintained. Stridulous patients also feel more comfortable with THRIVE on as it reduces the work of breathing by increasing tidal volume, reducing respiratory rate, increasing expiration time and therefore allowing re- recruitment of greater lung areas (while awake). Classical apnoeic oxygenation does not clear carbon dioxide and can give rise to acid-base disturbance, whereas THRIVE blunts the rise of CO2 during apnoeic periods. It is important to remember that THRIVE should not be considered a substitute for a definitive airway, and that it does not work with total airway obstruction, nor is it a rescue for desaturation in an anaesthetised patient. While the initial work has been done using THRIVE for transglottic surgery as the sole method of oxygenation, it is recognised that this forms a very small part of the general anaesthesia workload. Instead, the role it can play in preventing desaturation during airway management and the positive impact this could have in human factors/nontechnical skills is a very exciting development towards safer anaesthesia delivery.
Mr Omar Hilmi an ENT Consultant working at Glasgow Royal Infirmary, concluded the session with a talk entitled “Imaging of the Airway”. He started by emphasising that imaging should always be considered alongside clinical assessment and nasendoscopy, not in isolation. It is essential to have CT imaging when assessing the level and the extent of the tumour. It is also useful for establishing if there is a ‘straight line’ from mouth to larynx (as this will determine both laryngoscopy for anaesthesia and surgical access), if there is any tracheal displacement/tracheal narrowing, as well as when there is a clinically significant neck mass. Imaging performed acutely can also be very useful for diagnosing and planning purposes if it is agreed that it is safe for the patient to undergo a CT scan.
After coffee, the final session opened with Dr Ross Moy, an Emergency Medicine Consultant and Army doctor. He talked about “Tactical Aeromedical Evacuation”, and opened by stating the army medical aims that “no one should exsanguinate from compressible bleeding” and “no one should asphyxiate if they do not have a crushed airway”. He discussed the capabilities of the aeromedical evacuation unit: assessment and resuscitation, control of catastrophic bleeding, airway management including surgical airway, chest decompression, giving blood products, dynamic triage and dealing with multiple casualties. During resuscitation they aim for haemostatic resuscitation, give tranexamic acid early, control temperature actively, and use damage control surgery as part of the resuscitation when indicated. They have a 94% intubation success despite the challenging conditions -he attributed this to having a consistent team very familiar with their roles, all of whom undertake regular team moulage training, use of high dose muscle relaxant, no cricoid pressure and no in-line stabilisation regardless of injury, alongside routine debriefing and then clinical governance meetings.
The final speakers of the day were Drs Simon Crawley and Barry McGuire, both Anaesthetists at Ninewells Hospital. They engaged in a lively debate around “Scalp, bougie, tube will cause more problems than it will solve!” with Dr McGuire defending the motion and Dr Crawley opposing it. Several good points were made on both sides, with the highlight being Dr Crawley using a video of his 5 year old daughter performing the technique to show that with adequate training anyone should be able to carry out the task! The vote was very close, with Dr Crawley just shading it (that’s a white lie as I have to work with Barry). Finally, Dr Urquhart closed what was a very enjoyable and successful meeting. Thanks again to him and everyone else involved for all the hard work that went into organising the day.
He announced that next year the 7th annual meeting will be organised by Dr Crawley and a team from Ninewells Hospital in Dundee. It will be held at the Royal College of Surgeons in Edinburgh on the 10th of March 2017. Look forward to seeing you all there.