Operational Carbon Footprint of a Gastrointestinal Endoscopy Unit at a Regional Hospital in Japan.

BACKGROUND AND AIM: Gastrointestinal endoscopy is resource-intensive, but no carbon footprint data have been reported from a Japanese facility, and published estimates differ widely in system boundary. We quantified the operational carbon footprint of an endoscopy unit at a Japanese regional hospital and identified which emission sources are amenable to unit-level intervention.

METHODS

In this retrospective single-center study, we analyzed 794 consecutive procedures performed over 5 months at a 150-bed regional public hospital. Emissions from electricity, patient travel, medical waste, consumables, reprocessing chemicals, medical gas, and water were estimated according to the Greenhouse Gas Protocol using Japanese national emission factors and published life-cycle data. Patient travel was aggregated at the procedure level under two scenarios: procedure-day travel only (Scenario A) and visit-count-corrected travel (Scenario B). Sensitivity analyses addressed transport mode, air-conditioning load factor, and waste composition.

RESULTS

The operational carbon footprint was 6537.5 kg CO2e (CO2e) (8.23 kg CO2e per procedure) in Scenario A and 8042.1 kg CO2e (10.13 kg CO2e per procedure) in Scenario B. In Scenario B, electricity was the largest source (38.8%), followed by patient travel (35.3%) and medical waste (13.5%). Air conditioning accounted for 69.3% of electricity use. Waste generation was 0.80 kg per procedure, of which suction fluid bags represented 36.7%.

CONCLUSIONS

Electricity, dominated by air conditioning, was the largest operational emission source and is directly modifiable by the unit. Patient travel was of comparable magnitude but reflects healthcare access geography rather than endoscopic practice.