November 2022 – #TheAnaesthesiaBlog

This new guideline is without doubt one of the most important papers from 2022 and essential reading for all. Oesophageal intubation during attempted tracheal intubation could happen to any one of us, yet traditional teachings and practice might lead to misdiagnosis. The case of Glenda Logsdail demonstrates the very real consequences when things go wrong. The key elements of the paper are the 11 core recommendations, the criteria for ‘sustained exhaled carbon dioxide’ and an algorithm for what should happen when these criteria are not met. Because many will not be skilled with airway ultrasound and because most will not have even seen an oesophageal detector device, the guideline reinforces the recently published Association of Anaesthetists recommendation for flexible bronchoscopes to be available for every general anaesthetic. The paper is free for all forever and as we saw live at Annual Congress, the associated cognitive aids located in the right place at the right time might just save a life. Ahmad and Wong provide the accompanying editorial and discuss the likely real-world impact of the guidelines. Afterall, it is extremely difficult to quantify true implementation and adherence of the recommendations provided.

If the PUMA guideline was the most important paper from this year, the results from NAP7 promise to deliver the same in 2023. But before all is revealed, this new paper takes us through the methods in detail. That the authorship delivered the project during the COVID-19 pandemic is a remarkable achievement and underscores the drive and determination behind the whole team. Not only that, the NAP7 infrastructure was activated to monitor the impact of COVID-19 on anaesthetic and surgical activity between October 2020 and January 2021 (ACCC-track). One of the many difficulties faced was to derive a unified definition of ‘peri-operative cardiac arrest’, which has been a source of controversy for many years. Although these events are rare and there is a great deal to learn from the analysis of individual cases, the project will also report some interesting trends at a national level with implications for all doctors, patients and policy makers.

Was it worth treating patient with COVID-19 in critical care areas? This new prospective single centre study from Schallner et al. found that direct medical costs for the treatment of COVID-19 patients were higher than for other critically ill patients, which was not exclusively due to longer length of stay (Fig. 1). Despite these high costs, they conclude the associated care to be cost-effective and beneficial regarding QALYS gained in relation to other medical measures. In the associated editorial, Pandit highlights several limitations of the analysis which suggest that we should not allow these data to inform public policy.

**Figure 1** Comparison of ICU treatment costs and simplified acute physiology score-2 (SAPS-2)/therapeutic intervention scoring system (TISS) scores in patients with (black circles) and without (grey triangles) COVID-19. (a) Total treatment costs (£); (b) Treatment costs per day (£); (c) Mean daily SAPS-2/TISS scores. Circles and triangles are individual patients, thick lines are means and thin lines are SD.

Postoperative morbidity following colorectal surgery can only be improved if it is measured and modelled. This new study from Bedford et al. describes the development and internal validation of the PQIP colorectal risk model. It demonstrates good calibration to risk-adjust postoperative day 7 morbidity defined by the POMS in the setting of elective major colorectal surgery with discrimination performance superior to published morbidity risk models. In the associated editorial, Coulson et al. set the work in its context and describe a pyramid model of investigation into unexpected variation is proposed (Fig 2.).

**Figure 2** Pyramid model of investigation. Investigation should start at the base, progressing towards the apex if a cause for variation is not established.

This new study aims to break the cycle of unnecessary lengthy periods of pre-operative fasting by using iterative ‘plan-do-study-act’ methods. They managed overall to reduce the median liquid fasting time from 12 h to 2 h, which is in keeping with international guidance. The key factor here is use of the term ‘unrestricted’, because putting limits on pre-operative clear fluid quantity and time presents logistical issues for staff, patients and hospitals. Is pre-oxygenation with high flow nasal oxygen easier for the anaesthetist and more comfortable for patients as compared with a facemask? This new RCT from Merry et al. finds this to be the case albeit with no clinically relevant differences in effectiveness (Fig. 3).