The Carbon Footprint of Cataract Surgery in Wellington

Introduction: Efforts to improve the sustainability of ophthalmic care require methods to measure its environmental impact and a baseline measurement to compare against in the future. We aimed to measure the carbon footprint of cataract surgery in Wellington.

Methods: We used Eyefficiency, an application using established footprinting methods, to estimate the emissions produced by phacoemulsification surgery in two public and two private hospitals. We measured (1) power consumption, (2) procurement of disposable items and pharmaceuticals, (3) waste disposal emissions and (4) travel (other potential sources were excluded). Where possible we used New Zealand emissions coefficients.

Results: We recorded data from 142 cataract surgeries. The average emissions produced by cataract surgery in the region was estimated to be 152kg of carbon dioxide equivalent. This is equivalent to 62L of petrol and would take 45m2 of forest one year to absorb. The great majority of emissions were from procurement, mostly disposable materials, and the second greatest contribution was from travel (driving).

Conclusion: Estimating the carbon footprint of cataract surgery is becoming easier, but improved methods for measuring the footprint of procured supplies are needed. There are significant opportunities for emissions reduction in the most common surgical procedure in New Zealand.