Imperial College Healthcare NHS Trust redesigned its obstructive sleep apnoea diagnostic pathway, replacing a plastic-heavy, multi-trip hospital model with a home-testing service using a reusable wearable device. The change eliminates three hospital journeys per patient, saving an estimated 4.2 kg of CO2 equivalent per test, or about 12.6 tonnes annually. Plastic waste dropped 99%, from 100g to 0.36g per test. Median time to diagnosis fell from 352 days to under 135 days, and the outpatient waiting list shrank from over 3,000 to below 1,000. Patients save up to 82 minutes of travel time and up to £7.15 per test. The pathway also improved equity, reaching a higher proportion of patients from non-white ethnic backgrounds. It is now routine at Imperial and has been shared with five other NHS regions.
