Faculty Bibliography

Background: The healthcare sector contributes 10% of US greenhouse gas emissions (GHGs). Given the adverse health effects associated with GHGs, healthcare sector workers have a moral imperative to reduce these GHGs. Life Cycle Assessment (LCA) is a tool used to quantify environmental emissions associated with a product or process, including natural resource extraction, manufacturing, packaging, transportation, use, and disposal of materials. To quantify GHGs and help guide pollution prevention strategies, we applied LCA to the process of preparing a biopsy in a surgical pathology laboratory.
Design(s): A detailed analysis of the processing of a biopsy was performed at a large surgical pathology laboratory, and grouped into 11 steps. Each supply item, reagent, and capital equipment was catalogued, along with the number of individuals involved, and average duration of each step. Supply items were weighed and primary material types noted. The lifespan of each reusable item was estimated, and post-use treatment pathways, including disposal, were noted. Reagent quantity was allocated to a single case based on total bottles used in the lab over one week. Watt meters and equipment power ratings were used to estimate the energy consumption of capital equipment. A lifecycle inventory and impact analysis were performed to estimate GHGs. The LCA was performed comparing two scenarios as a sensitivity analysis: (1) a patient case with a single biopsy jar and (2) a patient case with three biopsy jars.
Result(s): The largest proportion of total GHGs was from processing the cassette(s) on the tissue processor (Leica ASP 300S), which contributed 0.085kg of CO2-equivalents (kg CO2e) for scenario 1 and 0.224 kg CO2e for scenario 2, or, in both scenarios, 31% of total emissions, of which 25% was attributable to production of reagents used. The second largest contributor to GHGs was receiving and accessioning the case in the lab, which contributed 0.051kg CO2e or 19% of total emissions in scenario 1, and 0.151kg CO2e or 21% of total emissions in scenario 2, attributable mostly to the jars being single use items. Sensitivity analysis showed that GHGs can range between -18% and +4% for scenario 1, and between -15% and +10% for scenario 2.
Conclusion(s): This study evaluates the processing of a surgical pathology biopsy using an LCA. Understanding the process steps that contribute to GHGs is essential for determining which parts of the healthcare sector could be effectively targeted for reducing emissions

Purpose: Eyefficiency is a cataract surgical services auditing tool that aims to help units worldwide improve their surgical productivity and reduce their costs, waste generation, and carbon footprint. Phase 1 pilot tested in India, UK and Africa in 2017; while Phase 2 had two rounds of beta testing with sites participating from 6 WHO/IAPB regions.
Method(s): Eyefficiency has been through 3 rounds of testing, pilot tests at 4 sites in 2017 and two rounds of beta testing with sites from 6 WHO/IAPB regions in 2018-2019. Test sites entered facility-level data (staffing, pathway steps, costs of supplies, and energy use) on the Eyefficiency website. They entered time-and-motion data on Eyefficiency app from 30 consecutive cases or 1 week of cataract surgery. Eyefficiency uses descriptive statistics and environmental Life Cycle Assessment (LCA) to quantify productivity, costs, and carbon footprint.
Result(s): Eyefficiency testing was completed by 10 surgical facilities (in Swaziland, Chile, South Africa, Mexico (2), Guatemala, New Zealand, India, UK, and Hungary). Per bed case duration ranged from 13 minutes to 73 minutes with the majority of the time at all sites spent operating. Cases per hour ranged from 0.9 to 4.5. A majority of costs appear to come from the purchasing pharmaceuticals, disposable surgical supplies and energy; while carbon emissions appear to come largely from manufacturing of supplies and transportation.
Conclusion(s): Results show variability in cataract surgery efficiency metrics across the world, with lessons to be learnt from sites with higher throughput, lower costs, and reduced resource use

Purpose: Operating theatres are some of the most energy and resource intensive areas for medical treatment. As a result of resource production, use, and disposal, emissions are generated that harm the environment and human health. New tools are emerging to quantify these emissions and this study seeks to understand the footprint of cataract surgery at a US facility and to identify opportunities for reducing emissions.
Method(s): Eyefficiency, a new international cataract surgical services auditing tool that enables carbon emission calculations per surgical case, was used to quantify associated greenhouse gas (GHG) emissions in terms of kilograms of carbon dioxide equivalents (kg CO2e) for cataract surgeries conducted in an outpatient centre in the US. These include emissions from supplies, energy, and reusable instruments in an average case. This site also conducted audits of pharmaceutical waste disposal to determine the quantity of unused and wasted products at the end of an average case.
Result(s): Preliminary Eyefficiency data shows that a majority of this sites' GHG emissions from cataract surgery are generated from procurement (production) of single use products and pharmaceuticals, electricity used in the operating theatre, and travel of staff. Of GHGs from pharmaceutical production, 60% can be attributed to unused drugs that are disposed of after the case.
Conclusion(s): There are many avenues available to reduce resource consumption and GHG emissions from cataract surgical care, but quantifying and understanding the sources of emissions is an important first step

Purpose/UNASSIGNED:We measured waste from glaucoma surgeries at an eye care facility in Southern India and compared these results to a community hospital in the United States. Methods/UNASSIGNED:The waste produced in the glaucoma operating room at Aravind Eye Hospital, Madurai, India from June 22 to July 15, 2015 was weighed and compared to the waste produced in the glaucoma surgical clinic in a Baltimore-area community hospital from one day of surgeries in August 2015. Results/UNASSIGNED:The average waste produced per trabeculectomy at Aravind was 0.5 ± 0.2 kg, compared to an average of 1.4 ± 0.4 kg per trabeculectomy (p < 0.05) at the Baltimore-area hospital. Waste from device surgeries and trabeculectomy with phacoemulsification was also quantified at Aravind, with averages of 0.4 ± 0.2 kg and 0.7 ± 0.2 kg respectively. Conclusions and importance/UNASSIGNED:The amount of waste per trabeculectomy at the Aravind Eye Hospital was significantly lower than the waste per trabeculectomy in the Baltimore-area hospital, even though the used and the apparent complication rates between Aravind and American eye hospital are comparable. Given efforts to decrease the environmental impact of health care, it is necessary to examine the waste produced from surgeries to determine if policy and legal changes in the United States could decrease surgical waste while not affecting the surgical complication rate.

Our study assesses the differences between regional average- and marginal-electricity generation mixes as well as the variability between predicted and observed energy consumption of a "conventional green" Leadership in Energy and Environmental Design (LEED) building and a Net-Zero Energy Living Building (NZEB). The aim of our study was to evaluate the importance of using temporally resolved building-level data while capturing the dynamic effects a changing electrical grid has on the life cycle impacts of buildings. Two static and four dynamic life cycle assessment (LCA) models were evaluated for both buildings. Both buildings' results show that the most appropriate models ( hybrid consequential for the LEED Gold building, hourly consequential for the NZEB) significantly modified the use-phase global warming potential (GWP) impacts relative to the design static LCA (49% greater impact for the LEED Gold building; 45% greater reduction for the NZEB). In other words, a "standard" LCA would underestimate the use phase impacts of the LEED Gold building and the benefits of the NZEB in the GWP category. Although the results in this paper are specific to two case study buildings, the methods developed are scalable and can be implemented more widely to improve building life cycle impact estimates.

BACKGROUND:The US health care sector has substantial financial and environmental footprints. As literature continues to study the differences between wide-awake hand surgery (WAHS) and the more traditional hand surgery with sedation & local anesthesia, we sought to explore the opportunities to enhance the sustainability of WAHS through analysis of the respective costs and waste generation of the 2 techniques. METHODS:We created a "minimal" custom pack of disposable surgical supplies expressly for small hand surgery procedures and then measured the waste from 178 small hand surgeries performed using either the "minimal pack" or the "standard pack," depending on physician pack choice. Patients were also asked to complete a postoperative survey on their experience. Data were analyzed using 1- and 2-way ANOVAs, 2-sample t tests, and Fisher exact tests. RESULTS:As expected, WAHS with the minimal pack produced 0.3 kg (13%) less waste and cost $125 (55%) less in supplies per case than sedation & local with the standard pack. Pack size was found to be the driving factor in waste generation. Patients who underwent WAHS reported slightly greater pain and anxiety levels during their surgery, but also reported greater satisfaction with their anesthetic choice, which could be tied to the enthusiasm of the physician performing WAHS. CONCLUSIONS:Surgical waste and spending can be reduced by minimizing the materials brought into the operating room in disposable packs. WAHS, as a nascent technique, may provide an opportunity to drive sustainability by paring back what is considered necessary in these packs. Moreover, despite some initial anxiety, many patients report greater satisfaction with WAHS. All told, our study suggests a potentially broader role for WAHS, with its concomitant emphases on patient satisfaction and the efficient use of time and resources.