The Nitrous Oxide Project: assessment of advocacy and national directives to deliver mitigation of anaesthetic nitrous oxide.

The environmental emissions attributed to anaesthetic nitrous oxide across the NHS are comparable to the carbon dioxide released by 135,000 flights from Frankfurt to New York. Much of these emissions are attributable to cumbersome and inadequately managed piped systems, resulting in excessive loss and waste. Since 2020, multiple hospital sites have been engaging with the Nitrous Oxide Project, a quality improvement method supporting a 'lean systems' approach to the provision of nitrous oxide. This review considers the frameworks supporting medical gas management in UK healthcare systems, and the impact of professional advocacy and medical gas stewardship to drive anaesthetic nitrous oxide mitigation in the NHS. Nitrous oxide mitigation efforts by grassroots and professional advocacy networks are enhanced through national centralised emission monitoring, distribution of data, technical information and provision of quality analysis. Given the climate harms of nitrous oxide, concerted efforts should be made to rationalise its use, and resources should be committed to supporting this at local, regional and national levels.

Using Bayesian Dynamic Borrowing to Maximize the Use of Existing Data: A Case-Study.

Bayesian Dynamic Borrowing (BDB) designs are being increasingly used in clinical drug development. These methods offer a mathematically rigorous and robust approach to increase efficiency and strengthen evidence by integrating existing trial data into a new clinical trial. The regulatory acceptability of BDB is evolving and varies between and within regulatory agencies. This paper describes how BDB can be used to design a new randomised clinical trial including external data to supplement the planned sample size and discusses key considerations related to data re-use and BDB in drug development programs. A case-study illustrating the planning and evaluation of a BDB approach to support registration of a new medicine with the Center for Drug Evaluation in China will be presented. Key steps and considerations for the use of BDB will be discussed and evaluated, including how to decide whether it is appropriate to borrow external data, which external data can be re-used, the weight to put on the external data and how to decide if the new study has successfully demonstrated treatment benefit.

Position statement from the Editors of Anaesthesia and Anaesthesia Reports on best practice in academic medical publishing.

It is essential that academic publishing complies with the highest standards in terms of ethics, research conduct and manuscript preparation. This protects the rights and welfare of research participants, ensures the integrity of study results and aids the communication and dissemination of novel findings into clinical practice. This position statement outlines the current policies and practices of the Editors of Anaesthesia and Anaesthesia Reports in relation to academic medical publishing.

Temperature changes of CoolSticks during simulated use.

INTRODUCTION: Cold sensation is often used to check neuraxial anaesthesia and analgesia. One opportunity to reduce the carbon footprint of anaesthesia is to replace vapo-coolant sprays such as ethyl chloride with a reusable device called the CoolStick, which is cooled in a refrigerator between uses. We designed a study to investigate how long the CoolStick remains at its working temperature, which we defined as <15 °C. METHOD: Experiments were undertaken using a thermocouple and digital temperature sensor attached to the CoolStick. We conducted two experiments to assess temperature changes following removal from the refrigerator for 10 min; the first investigated passive re-warming in the ambient theatre environment and the second investigated re-warming in simulated use. In our third experiment, we investigated the time taken to cool the device in the refrigerator, following use. Each experiment was repeated three times. RESULTS: In the passive re-warming experiment, the mean CoolStick temperature was 7.3 °C at the start, and 14.3 °C after 10 min. In the simulated use experiment, the mean CoolStick temperature was 7.3 °C at the start, and 18.9 °C at 10 min. In the cooling experiment, the mean CoolStick temperature was 15 °C at the start and 7.6 °C at 40 min. CONCLUSION: Our study indicates that it is feasible to use the CoolStick for providing cold sensation in clinical practice. Further study would be required to directly compare the effectiveness of the device to existing methods such as coolant sprays or ice in the clinical setting.

Implementing nitrous oxide cracking technology in the labour ward to reduce occupational exposure and environmental emissions: a quality improvement study.

Nitrous oxide, a potent greenhouse gas, is a common labour analgesic. One method which may reduce its carbon footprint is to 'crack' the exhaled gas into nitrogen and oxygen using catalytic destruction. In this quality improvement project, based on environmental monitoring and staff feedback, we assessed the impact of nitrous oxide cracking technology in the maternity setting. Mean ambient nitrous oxide levels were recorded during the final 30 minutes of uncomplicated labour in 36 cases and plotted on a run chart. Interventions were implemented in four stages, comprising: stage 1, baseline (12 cases); stage 2, cracking with nitrous oxide delivered and scavenged via a mouthpiece (eight cases); stage 3, cracking with nitrous oxide via a facemask with an air-filled cushion (eight cases); stage 4, cracking with nitrous oxide via a low-profile facemask, and enhanced coaching on the use of the technology (eight cases). The median ambient nitrous oxide levels were 71% lower than baseline in stage 2 and 81% lower in stage 4. Staff feedback was generally positive, though some found the technology to be cumbersome; successful implementation relies on effective staff engagement. Our results indicate that cracking technology can reduce ambient nitrous oxide levels in the obstetric setting, with potential for reductions in environmental impacts and occupational exposure.