Greener colonoscopy: effect of judicious carbon dioxide use and adoption of a non-leak gas/water valve on gas emissions during colonoscopy

Background Healthcare is responsible for ~4.4% of global carbon dioxide (CO2) emissions and endoscopy is the third largest contributor. This study aimed to quantify CO2 use in colonoscopy and assess the impact of different valves and practices on emissions and costs. Methods CO2 use was measured using a mass flow meter. The study compared CO2 flow using the standard gas/water valves, which continuously release CO2, with non-leak valves, which only release CO2 when depressed. It also assessed the impact of judicious use of CO2. An unpaired student t test was used to calculate statistical significance. Results Without a colonoscope attached, CO2 flow averaged 3.24 L/min. With the standard valve, flow dropped to 2.55 L/min, and with the non-leak valve, it was negligible. CO2 emissions were measured intraprocedurally during 351 colonoscopies. Using a non-leak valve and/or judicious CO2 application significantly reduced emissions compared with standard practice using a standard valve. This approach could reduce local emissions by >87%. Nationally, it would lead to emissions reductions of 106.5 metric tons of CO2 per annum with cost savings of >£260 000. Conclusion Judicious CO2 application and use of a non-leak valve significantly reduced CO2 emissions and costs in colonoscopy, contributing to the UK National Health Service goal of delivering a “net zero” service. We suggest turning off CO2 when not needed, adopting non-leak valves, implementing this practice in other endoscopic procedures, and encouraging all endoscope manufacturers to develop similar valves.

Citation

Anderson, R., Materacki, L., McGettigan, N., & Valori, R. (2025). Greener colonoscopy: effect of judicious carbon dioxide use and adoption of a non-leak gas/water valve on gas emissions during colonoscopy. Endoscopy, 10.1055/a-2716-4818. Advance online publication. https://doi.org/10.1055/a-2716-4818

DOI

10.1055/a-2716-4818

URI

https://hdl.handle.net/20.500.14709/1199