Environmental sustainability: Overview

With an estimated worldwide volume of 266 million surgeries in 2015, the call for general inhalation anesthesia is considerable. However, widely used volatile anesthetics such as N2O and the highly fluorinated gases sevoflurane, desflurane, and isoflurane are greenhouse gases, ozone-depleting agents, or both. Because these agents undergo minimal metabolism in the body during clinical use and are primarily (≥95%) eliminated unchanged via exhalation, waste anesthetic gases (WAGs) in operating rooms and postanesthesia care units can pose a challenge for overall elimination and occupational exposure. The chemical properties and global warming impacts of these gases vary, with atmospheric lifetimes of 1-5 years for sevoflurane, 3-6 years for isoflurane, 9-21 years for desflurane, and 114 years for N2O. Additionally, the use of N2O as a carrier gas for the inhalation anesthetics and as a supplement to intravenous (IV) anesthetics further contributes to these impacts. At the same time, unscavenged WAGs can result in chronic occupational exposure of health care workers to potential associated adverse health effects. Few adverse effects associated with WAGs have been documented, however, when workplace exposure limits are implemented. Specific measures that can help reduce occupational exposure and the environmental impact of inhaled anesthetics include efficient ventilation and scavenging systems, regular monitoring of airborne concentrations of waste gases to remain below recommended limits, ensuring that anesthesia equipment is well maintained, avoiding desflurane and N2O if possible, and minimizing fresh gas flow rates (eg, use of low-flow anesthesia). One alternative to volatile anesthetics may be total intravenous anesthesia (TIVA). While TIVA is not associated with the risks of occupational exposure or atmospheric pollution that are inherent to volatile anesthetic gases, clinical considerations should be weighed in the choice of agent. Appropriate procedures for the disposal of IV anesthetics must be followed to minimize any potential for negative environmental effects. Overall, although their contributions are relatively low compared with those of other human-produced substances, inhaled anesthetics are intrinsically potent greenhouse gases and pose a risk to operating-room personnel if not properly managed and scavenged. Factors to reduce waste and minimize the future impact of these substances should be considered.

Abstract
Background: Pharmacological treatments for critical processes in patients need to be initiated as rapidly as possible; for this reason, it is a standard of care to prepare the main anesthesia and emergency drugs in advance. As a result, 20%-50% of the prepared drugs remain unused and are then discarded. Decreasing waste by optimizing drug use is an attractive strategy for meeting both cost containment and environmental sustainability. The primary end point of this study was to measure the actual amount of drug wastage in the operating rooms (ORs) and intensive care units (ICUs) of a Regional Health Service (RHS). The secondary end point was to analyze and estimate the economic implications of this waste for the Health Service and to suggest possible measures to reduce it.

Methods: This prospective observational multicenter study was conducted across 12 hospitals, all of which belong to the same RHS in the north-east of Italy. Data collection took place in March 2018 and included patients admitted to ICUs, emergency areas, and ORs of the participating hospitals. Data concerning drug preparation and administration were collected for all consecutive patients, independent of case types and of whether operations were scheduled or unscheduled. Drug wastage was defined as follows: drugs prepared in ready-to-use syringes but not administered at all and discarded untouched. We then estimated the costs of wasted drugs for a 1-year period using the data from this study and the yearly regional pharmacy orders of drugs provided to the ORs and ICUs. We also performed a sensitivity analysis to validate the robustness of our assumptions and qualitative conclusions.

Results: We collected data for a total of 13,078 prepared drug syringes. Drug wastage varied from 7.8% (Urapidil, an alpha-1 antagonist antihypertensive) to 85.7% (epinephrine) of prepared syringes, with an overall mean wastage rate of 38%. The estimated yearly waste was 139,531 syringes, for a total estimated financial cost of €78,060 ($92,569), and an additional quantity of medical waste amounting to 4968 kg per year. The total provider time dedicated to the preparation of unused drugs was predicted to be 1512 working hours per year.

Conclusions: The overall extent of drug wastage in ORs and ICUs is concerning. Interventions aimed at minimizing waste-related costs and improving the environmental sustainability of our practice are paramount. Effort should be put into designing a more efficient workflow that reduces this waste while providing for the emergency availability of these medications in the OR and ICU.

Health care systems are responsible for an estimated 10% of total greenhouse gas (GHG) emissions and contribute to a variety of other environmental concerns, from particulate air pollution to being the second-largest producer of landfill waste in the United States. With the growing awareness of the impact health care has on the environment, the calls to acknowledge and mitigate these issues have increased. National and international organizations, including Practice Greenhealth and Health Care Without Harm, now provide tools, resources, and incentives to local and regional health care systems and facilities to analyze and reduce their environmen-tal footprints. Reductions in energy use and waste, moving away from reliance on heavy metals such as mercury, and more sustainable food systems in hospi-tals offer success stories for reenvisioning the role that health care can play in moving society toward a more sustainable future. Similarly, the use of inhalational anesthetics has received special attention because of the environmental externalities to the atmosphere and the impact on global climate change.