E. Yip, J. Blackburn, M. Aukland, A. Ijaz, C. Stendall, S. Iqbal

Birmingham Children’s Hospital, UK


The climate crisis is now an irrevocable reality. Our responsibility remains to mitigate ongoing emissions. Inhaled Anaesthetic Gases (IAGs) are greenhouse gases, with higher Fresh Gas Flow (FGF) rates resulting in higher use and wastage, and hence higher carbon footprint. Low-flow anaesthesia can reduce both financial and carbon cost by up to four times and is safely delivered in the paediatric population.


Our anaesthetic machines default to 4L/min FGF. Anecdotally, most cases are maintained on this intraoperatively.

Our aim was to assess current intraoperative FGFs, IAG use and wastage, with the objective to reduce these and hence the financial and environmental burden of our anaesthetics.

Strategy for Change

The project was registered with the hospital audit department. A baseline survey and audit were conducted. These were presented at the departmental audit meeting, along with education on impact of high flows on carbon footprint.

Interventions included; low-flow posters in theatres; reminder cards on anaesthetic machines; digital educational resources; and email reminders. These contained comparative information on different FGFs in financial terms (for our centre) and car-mile equivalent carbon emissions (e.g. 4L/min sevoflurane = £7.54/hour and 16 miles every hour, while 1L/min = £3/hour and 4 miles every hour).

Measure of improvement 

Pre-intervention audit was conducted over three consecutive days, with 147 cases. Interim data was obtained post-intervention, 2 months later, and comprised 130 cases. Induction/anaesthetic room machines were excluded. Data collected per case included; IAG type; consumption and uptake; use of TIVA (lack of IAG); lowest and highest FGF and total case time.

Post-intervention, the use of TIVA increased from 25% to 30% of cases. Most cases used sevoflurane (69% and 61%) where low FGF usage <1L/min increased from 22% to 35%. Mean consumption of sevoflurane per case decreased from 27.24 to 24.26 ml/hour. Isoflurane was only used in a small number of cases (5% and 9%).

Lessons learnt

Our interventions so far have resulted in reduction in IAG wastage. With further time and engagement, we anticipate increasingly better cost and carbon savings. The project has been well received in the department, and though on-going work is required to maintain engagement, it shows acceptance of sustainability QIs achieving the triple bottom line. In our centre, reducing FGFs from 4L/min to 0.5L/min could result in savings of at least £16,000/year and 20,000 kg CO2e/year. We have initiated this process with promising buy-in within our department.

Message for others

There is increasing appetite and acceptance for sustainability QIs. Initiating dialogue in sustainability can help change behaviours on a wider scale, resulting in improvement in the environmental impact of healthcare. Small changes aggregate to achieve large improvements over time, and just reducing FGF rates can generate significant monetary and carbon savings.


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