A case series of incidents reported to webAIRS relating to glucagon-like peptide 1 agonist use
The increasing prescription of glucagon-like peptide 1 (GLP-1) agonists presents a peri-operative challenge for anaesthetists. These drugs delay gastric emptying, potentially increasing pulmonary aspiration risk. Despite recent recommendations from the Australian and New Zealand College of Anaesthetists, Australian Society of Anaesthetists, and American Society of Anesthesiologists, there remain no formalised guidelines regarding preoperative optimisation for patients taking GLP-1 agonists. Given the current lack of evidence, we present a case series of incidents involving patients treated with GLP-1 agonists reported to webAIRS, a web-based anaesthetic incident reporting system in Australia and New Zealand. Among 11,700 reports from July 2009 to April 2024, 13 incidents related to GLP-1 agonist use were identified, including seven cases concerning aspiration. Patient factors potentially contributing to increased aspiration risks in these incidents included a higher body mass index, type 2 diabetes mellitus, gastro-oesophageal reflux disease, emergency case, and time from GLP-1 agonist cessation. Most incidents involved a rapid sequence induction for general anaesthesia with no cases utilising gastric ultrasound, preoperative nasogastric tube insertion, or intravenous erythromycin use. This case series highlights the potential concerns relating to GLP-1 treatment in the perioperative setting. Interdisciplinary collaboration and communication between anaesthetists, surgeons, general practitioners and endocrinologists are required to further investigate and establish preoperative guidelines for safe GLP-1 agonist use. Specifically, consideration in determining actual gastric contents of each patient despite generic fasting guidelines is needed. Early preoperative risk stratification should also improve patient safety and outcomes.
Exploring Safety-II principles in anaesthetic airway management - a qualitative analysis of difficult and failed intubations reported to webAIRS
Anaesthetic airway incidents persist as a significant concern in patient safety and, despite extensive investigations, continue to cause patient harm. Traditional safety investigations predominantly adhere to Safety-I principles, focusing on identifying and rectifying errors, often yielding limited new findings. In this analysis conducted within the webAIRS database, the focus shifted towards Safety-II principles. The aim of this study was to identify factors contributing to airway management safety by examining incidents that did not result in adverse patient outcomes. Incidents categorised as 'difficult intubation' or 'failed intubation' without causing harm to the patient and reported to webAIRS between 2016 and 2022, were included in the analysis.An inductive qualitative content analysis of narrative data from 129 such incidents revealed that the majority of reported events depicted scenarios deviating from controlled and planned circumstances. During the analysis four themes were identified: patient factors, system factors, individual anaesthetist factors and airway management strategy. Within the first three themes, multiple factors were linked to airway management strategies. The findings of this qualitative analysis show that 'Work as done' often differs from 'Work as imagined'.This qualitative analysis highlighted the dynamic nature of human management, as individuals respond to unplanned or unexpected events, showcasing adaptability and positive contributions to incident performance. Expanding the understanding of patient safety to also include Safety-II principles, provides a deeper and wider understanding of airway management safety.
A randomised, open-label trial of nebulised unfractionated heparin in patients mechanically ventilated for COVID-19
Nebulised unfractionated heparin (UFH) might reduce time to ventilator separation in patients with COVID-19 by reducing virus infectivity, pulmonary coagulopathy, and inflammation, but clinical trial data are limited. Between 1 July 2020 and 23 March 2022, we conducted, at two hospitals in Victoria, Australia, a randomised, parallel-group, open-label, controlled trial of nebulised UFH. Eligible patients were aged 18 years or more, intubated, under intensive care unit management, had a PO to FO ratio of 300 or less, had acute opacities affecting at least one lung quadrant and attributed to COVID-19, and were polymerase chain reaction-positive for SARS-CoV-2 or had further testing planned. The target sample size was 270, however, the trial was stopped due to slow recruitment. There were 50 enrolments, all of whom were analysed. The median age was 55 (interquartile range (IQR) 46-64) years, 28 (56%) were males, and 46 (92%) had acute respiratory distress syndrome. Twenty-seven (54%) were randomised to nebulised heparin and 23 (46%) to standard care. Nebulised UFH was administered to the heparin group on 6 (IQR 4-10) days; median daily dose of 83 (IQR 75-88) kIU. The primary outcome, time to separation from invasive ventilation to day 28 adjusted for the competing risk of death, was not significantly different between groups but took numerically longer in the nebulised heparin group (12.0, standard deviation (SD) 10.4 days versus 7.4, SD 6.9 days; hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.31 to 1.01, = 0.052). One patient died by day 28 in each group, fewer than expected. Time to separation from invasive ventilation among survivors to day 28 occurred more quickly than expected in the standard care group and was, without correction for multiple comparisons, significantly slower in the heparin group (11.3, SD 10.0 days, = 26 versus 6.4, SD 5.2 days, = 22; HR 0.52, 95% CI 0.30 to 0.92, = 0.024). Nebulised heparin did not reduce time to ventilator separation in intubated adult patients with COVID-19. The study is limited by the small sample size and potential for sampling bias. Further study is required.
James Young Simpson's : The first pamphlet on chloroform
James Young Simpson's is a rare pamphlet of which three copies have hitherto been documented. Two of the three known copies were inscribed by Simpson with the words 'proof copy'. A fourth copy of the pamphlet, also inscribed with the words 'proof copy', has been identified. Although regarded by Simpson as a proof copy, there is previously unreported evidence that the pamphlet was advertised by the publisher on 12 November 1847, published on 13 November 1847, and sold on that day by booksellers in Edinburgh. Thus, the pamphlet was the first published report of the use of chloroform as an anaesthetic agent. The pamphlet was issued 2 or 3 days before the well-known revised edition bearing the title , and one week before the publication of Simpson's papers on chloroform in and the .
Effects of polymyxin B haemoperfusion on septic shock caused by Gram-positive bacteria
Polymyxin B haemoperfusion is commonly used to adsorb endotoxins in septic shock caused by Gram-negative bacterial infections. Polymyxin B haemoperfusion has been reported to improve hypotension in Gram-positive bacterial infections; however, its efficacy and mechanism in treating such cases are unclear. We hypothesised that polymyxin B haemoperfusion would be equally effective in improving haemodynamics during Gram-positive bacterial infections as in Gram-negative bacterial infections. We conducted a retrospective study that included patients with septic shock admitted to the intensive care unit. The patients were divided into two groups according to bacterial culture results: Gram-negative rod (GNR) and Gram-positive coccus (GPC). We calculated the vasoactive inotropic score (VIS) before (0 h) and 2, 6, 12 and 24 h after polymyxin B haemoperfusion therapy. Data were analysed using two-way analysis of variance and post hoc tests for the associations between infection type and treatment time. Overall, 157 patients with septic shock were enrolled in the study: 81 and 76 patients were treated or not treated with extracorporeal haemoperfusion therapy, respectively. Although there was no significant difference in the VIS in polymyxin B haemoperfusion between patients with GNR and GPC infections, there was a significant decrease in the VIS over time, even when GPC was the causative organism. In addition, the degree of reduction in the VIS was significantly different in both the GNR and GPC groups compared with that in the non-extracorporeally treated group. Thus, polymyxin B haemoperfusion for septic shock caused by GNR reduced the VIS and could be effective even in cases of GPC infection.
Returning to work following parental leave: the experiences of Australian anaesthetists
With increasing gender balance in specialist medical training and employment in Australia, there is a corresponding need to consider how parental leave and subsequent return to work is managed in the workplace. An electronic survey exploring the experiences of pregnancy and return to work following parental leave was distributed by the Australian and New Zealand College of Anaesthetists (ANZCA). The return-to-work component of the survey evaluated parental leave and return-to-work patterns, lactation practices and facilities, supports and resources utilised during the return-to-work process. We report on 391 return-to-work episodes from 219 respondents. One hundred and seventy-two (79%) were specialists at the time of survey completion. Six to 11 months was the most frequent duration of parental leave, and this duration was associated with higher satisfaction levels than shorter durations of leave (odds ratio 5.44, 95% confidence interval 3.18-9.31, < 0.001). Breastfeeding continued in 246 (63%) return-to-work episodes, and absent or inadequate lactation facilities were reported in 239 (88%). In 227 (58%) return-to-work experiences, respondents received no formal support on returning to work. One hundred and thirty-five (62%) respondents did not utilise any existing return-to-work resources, and family and friends were the main source of support for 113 (52%) respondents. Return-to-work processes should be tailored to meet individual needs. Consistent with existing recommendations, satisfactory lactation facilities must be provided. We recommend that the period of one-to-one supervision be flexible and negotiated, to suit the unique return-to-work trajectory of each worker. Existing ANZCA resources could assist departments in supporting anaesthetists who return to work following parental leave.
Experiences of Australian anaesthetists and anaesthetic trainees of working whilst pregnant: Results of a national survey
Changing medical workforce demographics emphasise the need to understand and effectively manage pregnancy in the workplace. An Australian survey exploring pregnancy experiences of specialists and trainees working in anaesthesia received 242 responses describing 549 pregnancies. One hundred and sixty-two (67%) of these respondents were aged 31-40 years, 185 (76%) were specialists and 159 (66%) reported one or two pregnancies. Reported pregnancy complication rates were similar to national averages. Potentially harmful exposures included working >40 h per week ( = 298, 55%), ionising radiation and unscavenged gases. Other than ergonomic hazards and stress, exposures were not associated with an increase in self-reported complications. Moving heavy patients on a daily to weekly basis (278, 53%) was associated with an increased risk for any maternal complication; odds ratio (OR) 2.13, 95% confidence interval (CI) 1.37 to 3.33, 0.001. High or debilitating stress levels were associated with any maternal complication, OR 2.93, 95% CI 2.06 to 4.17, 0.001, and any adverse neonatal/fetal outcome, OR 1.72, 95% CI 1.10 to 2.69, = 0.018. The most common stress contributors were 'work-related', 'exams' and 'pregnancy anxiety'. Ninety-one (38%) respondents reported experiencing stigma or negative attitudes toward their pregnancy from anaesthetic colleagues. Overall, 171 (71%) of respondents were satisfied with their experience of working in anaesthesia whilst pregnant. Thematic analysis of free text comments identified three major themes: workplace culture, maternal and fetal wellbeing, and career impacts on both pregnancy and family planning. Development of multilevel mechanisms to guide and support pregnant trainees and specialists in anaesthesia is recommended to address these findings.
The validity of self-reported smoking status on day of surgery in a mixed elective surgery population
Rates of misrepresenting smoking status on day of surgery varies with the clinical context. In perioperative smoking cessation trials, participants in the intervention group might be more likely to provide untruthful data about quitting when they have received substantial quit support but continued to smoke. The objective of this study was to determine misrepresentation rates of smoking status on day of surgery in mixed elective surgical populations, comparing groups offered or not offered additional cessation support. We undertook a post hoc analysis of data from three published randomised trials at a Melbourne public hospital that incorporated interventions during the wait-list period aimed at increasing smoking cessation. Participants were smokers ( = 1413) who were randomised to minimal cessation help at wait-listing (control group) or significant assistance, for example, mailed nicotine replacement (intervention group). Quit by day of surgery claims were verified by exhaled carbon monoxide (true cessation <8 parts per million). Verified cessation (>24 h) before surgery occurred in 161/1413 (11.4%) while 44/1413 (3.1%) misrepresented quitting. Continued smoking was in 1208/1413 (85.5%). Misrepresentations were higher in the intervention/offer of help groups (4.1%) than control groups (1.7%) (odds ratio (OR) 2.46, 95% confidence interval (CI) 1.17 to 5.63, = 0.012). Offering cessation help increased quitting odds by 77%, (OR 1.77, 95% CI 1.24 to 2.52, = 0.002). In contrast to other studies, we found group allocation in cessation trial settings had a significant effect on misrepresentation risk. The implication of this is that biochemical verification of quit status is essential in trial contexts for accurate data collection and to prevent misclassification bias.
Anaesthetic practice and mortality in Scotland compared to England from 1847 to 1914
In the second half of the nineteenth century and up to the First World War, anaesthetic practice in Scotland differed markedly from that in England. Chloroform was invariably used in Scotland with apparent disregard for reports of deaths under its influence. By contrast, in England concern about chloroform deaths, which were subject to inquests there, led to ether often being chosen instead. This article examines the different interpretations and handling of chloroform deaths in the two countries, drawing on the medical journals of the period and archived documents. Quite symmetrical claims were made. Whereas in England the danger of chloroform was perceived to be an inherent property of the agent itself, in Scotland the blame was thrown on a timid method of administration. The interpretation in Scotland was supported by a network of doctors who promoted chloroform as effective, safe and easy to administer; manufacturers who had monopoly of its manufacture; and legal practitioners who were uninterested in investigating anaesthetic deaths. Although the reporting of anaesthetic deaths was flawed in England, underreporting was far worse in Scotland. The fear of anaesthetic deaths in England allowed the seeds of specialisation in anaesthesia to germinate, whereas in Scotland the downplaying of anaesthetic risk obviated the notion of such specialisation.
Perioperative anaphylaxis in Malaysia: A nine-year retrospective study
Diagnosis of perioperative anaphylaxis (POA) and identification of causative agents remain challenging. This study aimed to describe the estimated incidence, characteristics and causative agents of POA in Malaysia. This is a retrospective review of all cases of suspected POA referred to the only anaesthetic allergy centre in Malaysia from March 2014 to December 2022. One hundred and ninety patients with suspected POA of Grade 2 and above were included. Data on clinical presentation, severity, management, serum tryptase and subsequent allergy workup (including skin and serum testing results) of these patients were extracted from the database. Dynamic tryptase was elevated in half of the cases where tryptase results were available and skin tests were positive in 96% of these cases. Skin testing was positive in 113 patients (60%) overall, and more than 70% of Grades 3 and 4 anaphylaxis cases. Neuromuscular blocking agents (NMBAs) and antibiotics were the most commonly identified causative agents (27.4% and 23% respectively). The commonest NMBAs were rocuronium and atracurium, both commonly cross-reacting with cisatracurium. The overall cross-reactivity rate among NMBAs was 58%. For antibiotics, the commonest causative agents were cefuroxime, ceftriaxone and amoxicillin/clavulanic acid. Using these data, the estimated incidence of Grades 2-4 POA over this period in Malaysia was approximately 1 in 30,000 anaesthetics. However, owing to the voluntary nature of reporting, it is possible that this is an underestimate, particularly in relation to some milder Grade 2 cases which may have gone unrecognised or unreported.
The elective use of percutaneous transtracheal oxygen insufflation for laryngeal surgery in a patient with a known difficult airway
We report the case of successful elective percutaneous transtracheal oxygen insufflation in a patient with high-grade laryngeal stenosis, requiring repeat surgical laryngeal dilation, in the setting of multiple previous failed attempts at intubation and ventilation. This case report highlights the role of this technique as an initial management plan to provide general anaesthesia in a safe and simple way to patients with a known difficult airway. We also describe the use of an intravenous extension kit which allowed end-tidal carbon dioxide to be measured during transtracheal oxygen insufflation.
A randomised trial to assess the impact of midodrine on early mobilisation after elective primary hip replacement surgery
Early mobilisation following elective total hip arthroplasty (THA) facilitates quicker rehabilitation, and reduces complications and hospital length of stay. Reasons for delayed mobilisation are multifactorial, but the most common cause is orthostatic intolerance. Midodrine, an oral alpha-1 agonist, is used off-label for perioperative hypotension. However, there are few randomised trials assessing its use in the perioperative setting to improve patient outcomes. The aim of the study was to determine whether midodrine improves early mobilisation following primary THA, and whether this relates to reduced orthostatic intolerance. This prospective, triple-blinded, multicentre study involved 42 patients randomised to either placebo or 20 mg midodrine, 2 h before physiotherapy, on Day 1 postoperatively. The inclusion criteria were adults undergoing elective unilateral THA under spinal anaesthesia. The primary endpoint was the ability to walk 5 m with physiotherapists. Secondary endpoints included the incidence of orthostatic intolerance and hypotension. A preplanned interim analysis showed no statistical difference in ability to mobilise 5 m (78.26% vs 78.95%, = 1.0). There was no statistically significant difference in the incidence of orthostatic intolerance between the groups 17.4% vs 31.6% ( = 0.45). Pre-emptive use of midodrine did not improve patient mobilisation the morning after elective primary THA and had no significant effect on the incidence of orthostatic hypotension.
Expert opinions on the applicability of the European guidelines on postoperative delirium in Australia and New Zealand
Unrecognised drug error and subsequent airway management utilising ultrasound-guided cricothyroidotomy and Rapid-O2® oxygen insufflation
Tubeless microlaryngoscopy optimises surgical access but typically relies on total intravenous anaesthesia, commonly using propofol and remifentanil infusions. We present a difficult airway case where an unrecognised drug error during programming of an infusion pump resulted in unexpected apnoea. Open airway surgery proceeded with the use of a prophylactic cannula cricothyroidotomy using a Rapid-O2® insufflation device to provide rescue oxygenation. Furthermore, cricothyroid membrane identification failed with digital palpation but was successful with ultrasonography. While the latter is currently not considered the standard of care for preparing for front-of-neck access in a time-critical 'can't intubate, can't oxygenate' scenario, in our case it proved helpful.
The impact of the introduction of monitored anaesthesia care in the cardiac catheterisation laboratory on Clinical Review, Rapid Response, and Blue Code rates, and mortality
Most procedures in cardiac catheterisation laboratories (CCLs) have traditionally been performed under conscious sedation under the supervision of the treating proceduralist. With growing demand for more complex procedures to be performed, in emergencies and in patients with limited cardiorespiratory reserve, a reconsideration of the level of supervision provided is required. We conducted a retrospective cohort study of all patients who had CCL procedures and required an overnight stay at Royal North Shore Hospital during a 12-month period prior to introducing monitored anaesthesia care (MAC), compared with a 12-month period following introduction of MAC on selected weekdays. Primary outcomes were the difference in rates of Code Blue calls (triggering the cardiac arrest team), Clinical Reviews and Rapid Responses (defined as per the NSW Health 'Between the Flags' Deteriorating Patient Safety Net System) in the 24 h post-procedure between patients who did and did not have MAC. The secondary outcome was a difference in mortality (within 24 h of a procedure and in-hospital) between patients who did and did not have MAC. One thousand nine hundred and eight patients were analysed (926 pre-intervention, 982 post-intervention). We found no statistically significant difference in any of the primary or secondary outcomes between the pre-intervention and post-intervention patients overall. However, we found a statistically significant lower rate of Code Blue calls in patients who had MAC ( = 3, 0.6%) compared with no MAC ( = 31, 2.3%). We also found a significantly lower 24-h mortality in patients who had MAC ( = 1, 0.2%) compared with no MAC ( = 22, 1.6%), but no difference in overall in-hospital mortality.
Survey of administration of intravenous ketamine for perioperative pain management in Australia and New Zealand
Ketamine is an N-methyl-d-aspartate receptor antagonist approved for use in anaesthesia, with analgesic properties. Despite publication of numerous trials and expert guidelines on its use for pain management, administration of ketamine as part of multimodal perioperative analgesia remains 'off-label'. We conducted an online, prospective survey of ANZCA Fellows, exploring current prescribing practices of intravenous ketamine for perioperative analgesia. We surveyed 2000 Fellows and received 806 responses. The factors mostly likely to influence their administration of perioperative ketamine included pre-existing chronic pain, and heavy or multiple opioid use by patients preoperatively. Amongst respondents, less senior anaesthetists and those working in public hospitals were more likely to administer intraoperative ketamine. The surgical procedures most likely to result in ketamine administration intraoperatively were open pelvic/abdominal, thoracic and major spinal surgery, where ketamine administration was likely practice for the majority of respondents, with typical loading doses that ranged widely. The commonest choices of intraoperative loading dose were between 0.2 mg kg and 0.6 mg kg. The commonest choice of intraoperative and postoperative infusion rate was in the range of 0.1-0.2 mg kg h. Postoperative ketamine infusion was most commonly prescribed as third-line or rescue analgesia. The majority of respondents thought it either 'likely' or 'very likely' ketamine would reduce postoperative chronic pain after thoracic surgery, but not in other surgical categories. Our findings suggest that off-label perioperative administration of ketamine at analgesic dose ranges is routine or common practice in major surgery for a majority of specialist anaesthetists in Australia and New Zealand.
Improving the efficiency of sevoflurane delivery during general anaesthesia by educating and motivating anaesthetists to utilise the Volatile Efficiency Ratio
Volatile anaesthetic agents such as sevoflurane contribute to greenhouse gas emissions, and selecting low fresh gas flows on anaesthetic machines minimises their waste. Facilitating improvements in sevoflurane use requires the education, motivation, and standardised evaluation of anaesthetists. There is currently no standard of practice related to the efficiency of anaesthetic gas delivery per case. We conducted a multi-component study termed 'Low With The Flow' (LWTF) to directly address these requirements by educating and motivating anaesthetists to reduce fresh gas flow and thereby sevoflurane use. We introduced a novel metric, the 'volatile efficiency ratio' (VER), able to be calculated on Draeger Primus™, the Draeger Atlan™ family and Draeger Perseus A500™ machines, to audit sevoflurane use in a case-by-case fashion, and assess whether the intervention could achieve a set VER target. The LWTF intervention significantly improved the efficiency of sevoflurane delivery (VER 0.46 pre-intervention ( = 518) versus VER 0.57 post-intervention ( = 531), 95% confidence interval 0.092 to 0.129, 0.0001) resulting in a calculated average of 1.3 kg carbon dioxide equivalent emissions reduction and approximately AUD 3.50 saving per case. Consequently, the financial and environmental outcomes from sevoflurane delivery were considerably reduced. Our LWTF intervention provides a valuable model for other anaesthetic departments to investigate and address the global environmental and financial burdens related to their volatile anaesthetic use. For anaesthetists using anaesthesia machines that do not facilitate calculation of VER, an approach using components of our LWTF intervention may still reduce the environmental and financial impacts associated with administration of volatile anaesthesia.
The Bruck inhaler: An ether inhaler misattributed to Ludwig Bruck, an Australian medical publisher and supplier of medical equipment
The acquisition of an early ether inhaler stimulated research into several inhalers classified as Bruck inhalers. Ludwig Hermann Bruck was a German migrant who arrived in Australia in 1873. He became a medical publisher, importer of medical instruments, and made unique contributions to early Australian medical publishing, most significantly as the first publisher of . He also published which contained lists of unregistered medical practitioners and alternative therapists. In 1914, Bruck joined in business with Richard Thomson who had a company selling medical equipment to doctors and hospitals. During the First World War, both Bruck and Thomson were charged with trading with the enemy. Bruck committed suicide in August 1915 before the case was heard in court. We did not find any evidence that Bruck designed the inhaler later attributed to him. The Bruck inhaler is functionally similar to the Probyn-Williams inhaler and should therefore be regarded as a glass-domed version of this inhaler.