Maximising environmental sustainability on the return to in-person conferencing: Report from a 2500-person anaesthesia meeting in Sydney, Australia.

The COVID-19 pandemic disrupted medical conferences, where restrictions on public gatherings resulted in the postponement or cancellation of in-person meetings. Virtual events emerged as a substitute, providing a mechanism for scientific collaboration and continuing medical education with the additional benefit of low environmental impact. However, digital events may not meet all the needs of delegates, such as professional networking and social connection. In this report, we describe the methods used to minimise the carbon footprint of the 2023 Australian and New Zealand College of Anaesthetists' Annual Scientific Meeting, a conference with approximately 2000 in-person and 500 virtual delegates. A core group led the initiative, with all conference participants invited to contribute to this goal. A prospective prediction of carbon generation was undertaken, followed by the implementation of strategies to minimise and then measure the total carbon footprint of the event. Post-event calculations assessed the conference as better than carbon-neutral; however, delegate travel was not included in the analysis and therefore this result is tempered. Off-site workshops including virtual offerings were also not included in the analysis. We encourage medical conference organisers to collaborate with all stakeholders to embed low carbon-generation choices for their meetings where education, networking and social needs are also met.