The anaesthetic robotic revolution?

The July issue is now available online and next month will see a return to the distribution of printed copies of the journal to our readers. You can read all about the reasons for this, along with how we have adapted to the pandemic, in our new editorial which now features in our ‘accepted articles’ section. In this month’s issue, Biro et al. describe robotic endoscope-automated laryngeal imaging for tracheal intubation. A prototype robotic endoscope device was inserted into the trachea of an airway manikin by seven anaesthetists and seven novice participants. There was little difference between the groups in terms of success rate and duration of insertion (Fig. 1). Ahmad et al. list the many limitations of this study, such as the fact that tracheal intubation was not performed. That said, the device recognised glottic features and was able to steer the endoscope tip into the trachea automatically. This is truly novel. Will robots take our jobs? We only need to look to surgery to tell us that robots have made good surgeons better, and although anaesthesia might be an innovative specialty, we have not fully embraced the robotic revolution, just yet.

Figure 1 User interface composed of the tip camera video (a) and the device configuration feedback (b), and anatomical features detection (c to e). The square indicates the successful recognition of the laryngeal inlet. The white dot represents the detected entrance of the glottis, while the white cross aims into the direction the tip is pointing. This difference triggers the proposal to ‘move the device to the left’, which appears in the left upper corner of the screen. The entire larynx (double line square), the corniculate cartilages (dotted small square), glottis (full line square) and subglottic trachea (segmented square). On the video screen (a), these squares are colour coded for better differentiation.

This month’s issue contains several high impact papers on various aspects of caring for patients with COVID-19. First, Lyons and Callaghan discuss the use of high-flow nasal oxygen (HFNO) for such patients. We use it commonly for patients with respiratory failure, but there are theoretical concerns around the potential for aerosol generation. This is all challenged by the authors, who point to a lack of evidence on aerosol generation and the risk of infection with HFNO, and call for clinicians to remain open minded. The question is, do alternatives have a better risk-benefit profile, for both patients and healthcare workers? Ventilator splitting has received much attention, and this new paper describes how it might be achieved with standard hospital equipmentLee et al. report their experiences of battling COVID-19 from a tertiary academic medical centre in Singapore. Strategies included: containment; avoidance of health resource overburdening; optimisation of healthcare resources; and factoring in welfare and logistics. This can be compared with hospital surge capacity in a tertiary emergency referral centre during the COVID-19 outbreak in Milan, Italy. They issued an early warning (in late March) that hospitals should be prepared to face severe disruptions to their routine, and that it was very likely that protocols and procedures might require re-discussion and updating daily. The care of patients with chronic pain has been significantly impacted by the pandemic, and these new consensus recommendations from an international expert panel provide guidance on: the immune response; steroids; psychological, physical and social functions; in-person visits; telemedicine; biopsychosocial management; opioid prescriptions; anti-inflammatory drugs; and procedural precautions. Of course, no discussion of COVID-19 is complete without talking about personal protective equipment, and this review by Tim Cook is arguably the best there is. The infographic below contains all the key messages, but the full paper is well worth a read for everyone. You can also listen to a podcast on the topic from last month here

We also have a number of high-quality ‘NO-VID’ papers this month, including this narrative review of the anticipated difficult airway during obstetric general anaesthesia from Mushambi et al. They provide generic recommendations as well as updated decision aids for: the time and mode of delivery for a pregnant woman with an anticipated difficult airway; the general anaesthetic approach to such a patient; and an overview of all the included practice recommendations. This new safety guideline, jointly produced between the Obstetric Anaesthetic Association and the Association of Anaesthetists, describes practices around neurological monitoring associated with obstetric neuraxial block. Four main recommendations are given, which include: triggers to alert the anaesthetist; the use of straight-leg raise as a screening method; the likely timescale for resolution of neuraxial blockade; and the guidelines and policies maternity units should be expected to have in place (Fig. 2).

Figure 2 Summary of postpartum neurological deficits.

Elsewhere we have a study of the association of pre-operative anaemia with morbidity and mortality after emergency laparotomya prospective cohort study of clinician perception of long-term survival at the point of critical care discharge; and a retrospective observational study of variables associated with survival in patients with invasive bladder cancer with and without surgery. Over in Anaesthesia Reportsthis new report of a junior doctor’s experience of critical illness due to COVID-19 now had an Altmetric score of > 1000! It was featured by > 100 news organisations, including the mainstream media, and has won acclaim from doctors and patients alike. Other reports include: local anaesthetic resistance in a patient with Ehlers-Danlosintra-abdominal nasogastric tube placementparatracheal abscess formation following tracheal intubationthe anaesthetic management of a patient with an isolated cortical vein thrombosis for emergency caesarean sectiontransient paraplegia due to subarachnoid haemorrhage following spinal anaesthesia; and unexpected difficult airway management in a transgender female patient

Join us over on Twitter as we discuss every paper from the issue in detail, with each made free for a day for all!

Mike Charlesworth and Andrew Klein

Preventing major airway complications

Every anaesthetist fears the moment they might become faced with a ‘can’t intubate, can’t oxygenate’ (CICO) scenario, but thankfully such events are exceedingly rare. They nevertheless receive much attention in the academic literature. The results from this online survey of Australian and New Zealand anaesthetists finds that most hospitals keep CICO equipment in every anaesthetic room in dedicated packs. As this is probably not common practice elsewhere, maybe it is probably about time we all caught up. Kelly and Duggan discuss preparing for and preventing CICO events, and call for clinicians’ worldwide to examine the design of their working environment. At the same time, the need to prepare for CICO events is superseded, arguably, by the need to prevent them from happening in the first place. Perhaps it is good timing then, that Chrimes, Higgs and Sakles write in this month’s issue to welcome us to the era of universal airway management. Their guidelines are anticipated eagerly.

This new pilot study from Deng et al. is an excellent example of how such a study should be designed and reported. They present important data that will hopefully allow for a larger, definitive randomised controlled trial of standard vs. augmented systolic blood pressure management during endovascular thrombectomyWiles discusses the relevant literature on the relationship between anaesthetic technique, blood pressure monitoring and outcomes for patients undergoing mechanical thrombectomy after ischaemic stroke. He argues a greater focus on precision medicine is required, which includes individualised objectives and attention to detail. Is it time for bespoke haemodynamic targets? Such an aim might seem more biologically plausible than a simple choice between general anaesthesia and conscious sedation (Table 1).

Airway protection with reduced risk of pulmonary aspiration of gastric contents (most patients do not present fasted).Slower door‐to‐groin puncture time and thus may delay vessel recanalisation.
Less patient movement which is desirable from the perspective of the interventional radiologist and may reduce procedural time and complications.Potential for a greater degree of iatrogenic hypotension
Lower potential for patient discomfort.Unable to monitor neurological status intra‐operatively.
Ensures direct anaesthetic involvement in the procedure which may secondary benefits such as: dedicated intra‐operative clinical monitoring; assessment and correction of volaemic status; and assistance with postoperative care destination (e.g. critical care admission).Risk of postoperative hangover effect with potential for POCD/POD.
Table 1 Advantages and disadvantages of general anaesthesia (including tracheal intubation) for mechanical thrombectomy.

This new editorial is extremely timely, even though it was written at the end of 2019. Kelly et al. discuss resilience in the context of lessons learnt from the military. They remind us that resilience is more than ‘toughness’, and involves the ability to manage the breadth, depth, intensity and chronicity of the demands placed upon us. In the wake of passing the peak of COVID-19 cases in the UK and elsewhere, the messages contained, such as strategies to improve team resilience, are essential reading for all. In early March, we received our first COVID-19 paper from a group of Italian authors documenting their clinical experiences and recommendations. It has since been cited 32 times and achieved an Altmetric score of > 340! We then went on to publish these consensus guidelines for managing the airway in patients with COVID-19, which has now been cited 34 times and has an Altmetric score of > 500! We hope these and other publications, such as this simulation study to evaluate the operational readiness of a high-consequence infections disease intensive care unit, have contributed to better clinical care during what has been an extremely difficult time for us all.

This new review from Lindsay et al. examines representation of patients in peri-operative randomised controlled trials in terms of age, sex, race and ethnicity. They found included trials were insufficiently representative, with race and ethnicity seldom reported. Overall, study populations were younger (Fig. 1), which perhaps presents issues in areas such as orthopaedic and trauma surgery research. They recommend that unnecessary age discriminatory exclusion criteria, including age limits, should be avoided. This systematic review by Heesen et al. pits phenylephrine and noradrenaline against each other for the management of hypotension associated with spinal anaesthesia in women undergoing caesarean section. They found that noradrenaline may preserve haemodynamic stability to a better extent than phenylephrine. They also conclude that an effect of noradrenaline on the rate of fetal acidosis cannot be excluded, which could be due to the β‐stimulating properties of noradrenaline. However, they warn of a lack of data as these conclusions come from single trials only. It looks like this one is far from over!

Figure 1 Bubble plots for each surgical category showing the difference between the mean or median age of the randomised controlled trial population and the mean age of the equivalent populations in the English hospital registry, according to the middle year of study recruitment. Marker radius is proportional to the number of study participants.

Elsewhere this month, we have: a sub-analysis of pooled data from two prospective studies on 10 kHz spinal cord stimulation for the treatment of non-surgical refractory back painan analysis of patient and surgery factors associated with the incidence of failed and difficult intubation; and a randomised controlled trial of the effect of low-dose naloxone infusions on the incidence of respiratory depression after intrathecal morphine administration for major open hepatobiliary surgery. Over in Anaesthesia Reports, we have a report of airway obstruction during general anaesthesia in a patient with a vagal nerve stimulator. Make sure you send your reports today for an efficient and friendly peer review service, together with the chance to get a publication in a well-read PubMed listed publication!

Keep your eyes out for new about our next TweetChat, which we hope to bring to you very soon, and make sure you check out our complete free to access COVID-19 collection!

Mike Charlesworth and Andrew Klein