Reducing waste and environmental impact of high-volume eye surgeries

May/June 2023 | Volume 22 Number 3

In this photo, two health care professionals, recognizable due to their scrubs, sit on a stack of garbage bags

Photo courtesy of EyeSustainRegulations meant to protect patients dictate the use of non-reusable supplies, resulting in a large amount of waste. “If global health care were a country, it would rank number five in terms of total emissions.”

The climate crisis may disrupt eye care delivery (especially in the most vulnerable populations), while also increasing the risks for many eye diseases, such as cataract and infections, due to increased UV radiation, drought, weather extremes, and infectious diseases, according to the International Agency for the Prevention of Blindness. If global warming intensifies, it is likely that the number of people living with blindness—currently about 43 million—and the number of those with moderate to severe visual impairment—about 295 million—will rise. Much of this increasing disability will occur in low- and middle-income countries, where populations generally have less access to ophthalmic care to prevent or reverse eye disease.

At a recent CUGH session, Dr. David F. Chang, ophthalmologist from the University of California, San Francisco, warned the WHO has declared climate change the single greatest threat to human health. He also pointed out the concerning irony that the health care sector is responsible for 4.4% of all global greenhouse gas emissions, of which 71% arise from the manufacture, use, and disposal of medical supplies. He stated: “If global health care were a country, it would rank number five in terms of total emissions. U.S. health care alone would rank number 13.” Operating rooms account for a major share of health care's carbon footprint through the generation and disposal of enormous amounts of surgical waste.

Follow the LMICs

As a specialty, ophthalmology has the highest volume of surgeries in medicine. This prompted Chang to co-found EyeSustain, a global consortium of 40 ophthalmology societies. “We believe there is a pressing need to reduce the environmental impact of cataract and other eye surgeries, which are increasing in volume as our population ages,” Chang said. “Because we have the highest surgical volumes, ophthalmology has a unique opportunity—and an obligation—to make our highest volume procedures more sustainable.”

For both guidance and inspiration, Chang turns to southern India’s Aravind Eye Care System.

Founded in 1976, Aravind encompasses 14 eye hospitals in Southern India. Collectively, they perform the highest volume of cataract surgery in the world and half of their patients receive care either free of charge or at a heavily subsidized rate. Aravind pursues its mission of eliminating needless blindness by providing large-volume, high-quality and affordable care. “If you want to learn how to be more efficient and sustainable, you can look to low- and middle-income countries, because they already are most efficient—they don't have the luxury of wasting money or resources,” said Chang.

Evidence-based procedure

To maximize cost effectiveness of care, every Aravind hospital routinely reuses surgical gowns, gloves, irrigation bottles, phaco cassettes, tubing, cannulas (small tubes for insertion into a body cavity or duct), metal blades, and both topical and intraocular drugs, Chang noted in a recent editorial published in the Journal of Cataract & Refractive Surgery. (A phaco cassette is a type of cartridge inserted into the machine needed to perform phacoemulsification, a procedure used to remove the natural lens of the eye during cataract surgery.) Aravind hospitals also simultaneously prepare and operate on multiple patients (none required to wear hospital gowns) within the same operating room.

One study found that carbon emissions generated by one phacoemulsification at an Aravind center are approximately 1/20 of those generated by the same procedure in the United Kingdom. Each of Aravind’s practices (other than topical drug reuse) is a forbidden infection control violation in the U.S., noted Chang. Aravind’s postoperative endophthalmitis (POE) rate, then, should be much higher than in the U.S. where most supplies are discarded after single use to prevent infection. “In fact, it is not,” noted Chang. The POE rate for 2 million consecutive Aravind cataract surgeries between 2011 and 2018 was 0.04%. Comparatively, the American Academy of Ophthalmology’s Intelligent Research in Sight (IRIS) registry reported an identical 0.04% POE rate for 8.5 million consecutive cataract surgeries performed in the U.S. during an overlapping period.

Chang explained that cataract surgery is a relatively clean procedure with a low risk for microbial aerosolization and cross-contamination. “Many policies mandating single use of operating room supplies for ophthalmology are not evidence-based, and some are universal general surgery guidelines that are applied to our cases by default,” said Chang. “The Aravind data suggest that mandating single use of so many supplies and drugs is not necessary but generates a huge amount of needless waste and carbon emissions."

Changing protocols & regulations

Most ophthalmologists want manufacturers to provide more reusable options for surgical supplies, drugs, devices, and instruments, said Chang. In two large surveys of ophthalmologists conducted by Chang and his colleagues, eight to 10 times as many surgeons would prefer a reusable over a disposable instrument of equal cost. Most ophthalmologists also want more discretion to determine when and which items can be safely re-sterilized and reused.

“Although physicians can practice medicine off-label, we are paradoxically not allowed to reuse a product that is labelled single use,” said Chang. “It isn’t necessarily safer, but it is more profitable and easier for the manufacturers to gain regulatory approval if their products are labelled single use.”

He added that another big source of carbon emissions is needless waste of surgical medication. “Drugs have a disproportionately large carbon footprint because of the raw materials and manufacturing process.” While nearly every ophthalmologist feels it’s safe to use a multidose bottle, those actually doing so amounted to less than half of those surveyed, said Chang, who noted that many hospitals require discarding an entire 15 ml multidose eyedrop bottle after placing just one drop in a preoperative patient.

How can ophthalmologists in high-income countries improve sustainability now?

EyeSustain’s website has a seven-point pledge that eye surgical facilities can take. Chang suggests using multidose topical bottles on multiple patients and eliminating patient gowns and full body draping to decrease waste. Surgeons should eliminate seldom-used supplies from their custom surgical packs, replace disposable with reusable instruments where possible, and use alcohol-based hand scrubbing instead of scrub sinks for surgical prepping.

In one ophthalmology department, doing this saved 61,631 liters of water per operating room annually, which translates to up to $348,000 in scrub time saved per operating room during the same period. Chang said, “I think educating your staff about the environmental impact of unnecessary surgical waste is also important. They're the ones who can help you figure out how to be more sustainable.”