Life Cycle Analysis in Anesthesiology

Rationale for LCAs

• The medical ethics principle nonmaleficence (primum non nocere, first do no harm) broadly includes the need to reduce health care-associated emissions, promote population health, and provide high quality care without unnecessary waste.
• Health care as it is currently practiced contributes significantly to greenhouse gas emissions and pollution, worsening the climate crisis and harming patients. Health care sector pollution and emissions are responsible for almost 5% of global emissions and contribute to excess morbidity and mortality.^1,2
• Provision of health care is highly resource-intensive, and many have chosen to shift towards single-use disposable products for convenience and the notion that they may reduce infection (i.e., disposable plastic gowns, disposable laryngoscopes/blades, etc.) without full consideration of downstream effects such as environmental impact, and often without evidence of superiority.
• Many organizations have dedicated time and energy to minimizing the environmental impacts of medical treatments; however, significant challenges remain. Generation of waste is one of these challenges, as health care-generated waste is complex and expensive to manage, with over 6 million tons of waste generated annually.³

Methodology

• LCA assess the environmental impacts of a product or service throughout its entire life cycle (Figures 1 and 2). In the health care industry, LCAs are utilized to evaluate the environmental impacts of medical devices, pharmaceuticals, other health care products, and the delivery of health care services.⁴
• More broadly, LCA methodology can be applied to evaluate the environmental impacts of health care facilities, including the energy and water use associated with lighting, heating, and cooling, as well as the impacts of waste generation and disposal.
• Most LCAs have found that single use items contribute to higher emissions than reusable alternatives, though variables such as limited natural resources (i.e., water) and use of electricity from nonrenewable polluting sources can make reusable options less desirable.

Selection of LCA Related to Anesthesia Care

Anesthetic Drugs⁵

• Desflurane has largest greenhouse gas (GHG) impact (15 times more than isoflurane, 20 times more than sevoflurane).
• Nitrous oxide (N₂O) has large impact due to high global warming potential (GWP) and high concentration for clinical effect.
• Propofol infusion has a much smaller impact (1000 times less than desflurane or N₂O).

Laryngoscope Handles and Blades⁶

• A single use disposable (SUD) plastic handle generates an estimated 16-18 times more carbon dioxide equivalents (CO₂e) than reusable steel (low-level disinfection).
• A SUD plastic tongue blade generates an estimated 5-6 times more CO₂e than reusable steel (high level disinfection).
• SUD metal components generated much higher emissions than all alternatives.
• Reusable handles are more economical than SUDs if they last through 4-5 uses, and reusable blades 5-7 uses, before loss.

Laryngeal Mask Airways (LMAs)⁷

• Reusable silicone LMAs were found to have a more favorable environmental profile than the disposable polyvinyl chloride LMAs. Reusable LMAs have a 7.4kg CO₂e over their life cycle, compared to 11.3kg CO₂e for 40 disposable LMAs.
• There is an impact from reusable LMA from washing and sterilization.
• There is an impact from disposable LMA from production (polymers), packaging, waste, etc.
• Discarding reusable LMAs prior to end of life should be avoided. There are about 40 uses or higher with proper handling).
• If using disposable LMAs, they should be purchased in bulk and high impact plastics (PVC) should be avoided.

Anesthesia Equipment (Airway Supplies, Breathing Circuits)⁸

• Reusable supplies have lower costs.
• Energy source determines much of the CO₂ emissions from reusable equipment. This varies by country/region.

Limitations

• These analyses are specific to the location in which they are performed and use calculations that are derived from the availability of local resources, energy sources and waste streams. Therefore, the results may not be applicable to other facilities or geographic regions.
• In addition, regulations vary by country and region, and hospitals may have their own internal policies that must be considered. Readers should carefully analyze any LCA to determine how applicable it is to their region and institution and for any methodological assumptions or choices that may impact interpretation.
• It may be challenging to fully account for the downstream pollution associated with products or devices, for example, the impact of microplastics.

Gaps in Knowledge

• LCAs have been completed on a small subset of health care processes and products. There is a great need for expanded LCAs in health care, perioperative care, and anesthesia delivery.
• A database of health care LCAs⁹ has been created, but users must exercise caution as methodology can vary, and conclusions may not be broadly applicable.