At Vanderbilt University Medical Center, a team of investigators is taking steps to quantify health care’s climate impact – one surgery at a time.
In a study comparing robotic (rVHR) and open ventral hernia repairs (oVHR), they examined point-of-care costs and associated economic sectors to determine the cumulative environmental impacts of procedure-associated products and processes.
The results demonstrate that robotic hernia repair causes significantly greater environmental impacts than open repair.
“While robotic surgery has a higher environmental impact in the operating room, it also decreases hospital length of stay and opioid use,” said Joseph Blankush, M.D., a physician resident in Vanderbilt’s Division of General Surgery and first author on the study. “In general, we are looking to show that regardless of the procedure, the scale and volume of health care delivery, in its current format, causes significant environmental impact.”
Health Care’s Global Footprint
The health care sector’s global climate footprint is equivalent to 4.4 percent of net carbon emissions, according to a report from the nonprofit Health Care Without Harm. The United States health care sector accounts for 27 percent of these global health care-associated carbon emissions and 8 to 10 percent of the nation’s total emissions.
Measuring the fallout of these emissions in terms of downstream environmental impact such as acidification of water, airborne particulate matter and drought, among other factors, the United States population annually loses 405,000 disability-adjusted life-years (DALYs) – a measure of disease burden that translates to the number of lifespan years lost due to ill health, disability or early death.
“As physicians, we’re laser focused on what we do in the hospital, but we have to remember that there’s a global system around everything,” said Joseph Broucek, M.D., co-director of the hernia center in the Division of General Surgery at Vanderbilt. “We think we’re doing a lot of good in the OR, and overwhelmingly we are, but the whole industry has grown up around optimizing the supply chain with no real vision of environmental impact.”
Research Inspired by Shortages
The team’s work was sparked by a conversation concerning the mesh used in hernia repair. Supply chain has been tenuous during the pandemic, and Vanderbilt – like most other institutions – has experienced product shortages. The surgeons imagined how helpful it would be if they could 3D print the mesh in real time in the OR, as opposed to purchasing, shipping, and storing quantities.
“Impact studies have tended to focus on waste production in the OR – the cost of keeping the lights on in the hospital, the association with anesthetic gases in CO2 emissions, solid waste production,” Broucek said. “But the bulk of the impact comes from supply chain and sourcing.”
With a grant from the Society of American Gastrointestinal and Endoscopic Surgeons, Broucek, Blankush and colleagues used the two approaches to hernia repair to evaluate comparative carbon footprints.
“Regardless of the procedure, the scale and volume of health care delivery, in its current format, causes significant environmental impact.”
Their model uses point-of-care product costs and analyzes associated economic sectors to determine cumulative cradle-to-grave environmental impacts of procedure-associated products and processes. Environmental impact is quantified using economic input-output life cycle assessment methodology.
The aim is to create datasets and computer models that can be used to analyze any surgical process.
“It all boils down to raw materials and processes; because others had established the basic data, we were able to take it to the CPT [Current Procedural Terminology] code level,” Blankush said. “These are all data extrapolations, but this gives us the opportunity to present them in a way that matters to people.”
Technology’s Expanded Footprint
Fifteen cases each of rVHR and oVHR with myofascial flap creation and mesh implantation were included in the comparative analysis.
“We think we’re doing a lot of good in the OR, and overwhelmingly we are, but the whole industry has grown up around optimizing the supply chain with no real vision of environmental impact.”
Overall, rVHR demonstrated significantly larger environmental impacts across all categories, generating on average 141 percent more greenhouse gas emissions. Downstream environmental effects caused an incremental 1.9×10-3 DALYs per rVHR, 4.7×10-3 DALYs overall per procedure.
“No one is arguing that we shouldn’t be doing surgery – some similar models have suggested that seven to nine DALYs are added to someone’s life if you do a hernia repair,” Broucek noted. “But extrapolate the data over the millions of surgeries performed annually, and the DALY component is equivalent to 40,000 to 50,000 deaths per year that can be attributed to the health care system.”