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An Introduction to ASPAN's Waste Anesthesia Gases (WAGs) Position Statement

      Nurses are the largest discipline in the healthcare workforce, accounting for 59% of the healthcare professionals and approximately 4 million strong in the United States alone.

      World Health Organization. State of the world's nursing report 2020: investing in education, jobs and leadership. 2020. Accessed November 22, 2022. https://www-who-int.proxy.library.vanderbilt.edu/publications/i/item/9789240003279

      Patients come to hospitals for nursing care, and nurses are undoubtedly the most precious resource of hospitals and healthcare. However, for the estimated 60,000 nurses in the perianesthesia setting, there is an invisible hazardous occupational exposure that occurs every day in the Post Anesthesia Care Units. This hazard is exposure to waste anesthetic gases (WAGs) that the immediate post procedure general anesthetic patient exhales (95% unmetabolized) into the nurses breathing zones as they are delivering patient care.
      • Kharasch ED
      Biotransformation of sevoflurane.
      ,
      • Sherman J.
      • Le C.
      • Lamers V.
      • Eckelman M.
      Life cycle greenhouse gas emissions of anesthetic drugs.
      ASPAN is concerned about this unrecognized and unregulated occupational exposure and partnered with the American Industrial Hygiene Association to draft a position statement on WAGs. This statement was approved by the 2022 to 2023 ASPAN Representative Assembly at the 2022 National Conference in Philadelphia, PA.

      Rational for Concern

      The World Health Organization estimates that in order to achieve global healthcare coverage by 2030, we will need approximately 6 million more nurses.

      World Health Organization. State of the world's nursing report 2020: investing in education, jobs and leadership. 2020. Accessed November 22, 2022. https://www-who-int.proxy.library.vanderbilt.edu/publications/i/item/9789240003279

      With such a demand for a healthy nursing workforce, putting measures into action to protect both current and future nurses’ health is paramount. The first journal article discussing the negative health effects associated with occupational exposure to WAGs was published in 1967.
      • Vaisman A.I.
      Working conditions in surgery and their effect on the health of anesthesiologists.
      In the five decades that followed there has been numerous and compelling evidence published reporting a relationship with WAG exposure and poor health outcomes including headaches, fatigue, impaired judgment and coordination, renal and liver diseases, certain cancers, miscarriages, low birthweights, congenital abnormalities, infertility, genetic damage, bone marrow suppression, and impaired B12 metabolism.

      American Industrial Hygiene Association & ASPAN. Recognition, Evaluation and Control of Waste Anesthetic Gases in the Post-Anesthesia Care Unit. AIHA & ASPAN. 2021

      In 1977, the National Institute of Occupational Safety and Health release their recommended exposure limits (REL) for all anesthetic gases.

      Centers for Disease Control and Prevention. Criteria for a recommended standard: Occupational exposure to waste anesthetic gases and vapors. 1977 National Institute for Occupational Safety and Health. Retrieved November 18, 2022, from https://www.cdc.gov/niosh/docs/77-140/default.html

      This promoted research on the effects of occupational exposure, the means for preventing occupational injuries, and the recommended occupational safety standards. NIOSH made recommendations in four areas of occupational health:
      • scavenging and reducing exposure to trace concentrations of WAGs,
      • work practices to minimize WAG concentrations,
      • medical surveillance for possible occupational exposure in the healthcare environment, and
      • monitoring of WAGs.
      NIOSH recommended in 1977 that workers should not be exposed to halogenated agents at concentrations of less than 2 ppm when used alone, or less than 0.5 ppm when used in combination with nitrous oxide, over a sampling period not to exceed 1 hour.

      Centers for Disease Control and Prevention. Criteria for a recommended standard: Occupational exposure to waste anesthetic gases and vapors. 1977 National Institute for Occupational Safety and Health. Retrieved November 18, 2022, from https://www.cdc.gov/niosh/docs/77-140/default.html

      NIOSH has also recommended that occupational exposure to nitrous oxide, when used alone, should not exceed 25 ppm during the time of anesthetic administration. Additionally, NIOSH stated that all anesthetic gas machines, non-rebreathing systems, and t-tube devices should have an effective scavenging device that collects all WAGs. Also, they provided best practice recommendations such as turning on the scavenging system before administering anesthetic gases to the patient to minimize WAG exposure to medical staff.
      While these measures have long been in place for the operating rooms, there has been little recognition of these gases in other areas of the hospital (PACU, Labor & Delivery, cardiac cath labs, endoscopy labs, Trauma Units, etc.). The immediate post procedure general anesthesia patient serves as a source of WAGs as they exhale these unmetabolized anesthetic agents in areas unequipped with any engineering controls, regulations, or even awareness of this hazard. Badgwell et al
      • Badgwell J.M.
      The postanesthesia care unit: A high-risk environment for bloodborne and infectious respiratory pathogens.
      published a review of the literature related to PACU nurses exposure to WAGs, concluding that the concentration of these gases exceeding NIOSH RELs within the breathing zone of PACU personal and discussing engineering source controls to scavenge these gases. The past decade, additional articles published on WAG levels in the PACU have strengthened these findings. It has been estimated if PACU nurses can detect the odor of these anesthetic gases, the concentrations are 125 times above the REL set by NIOSH.

      American Industrial Hygiene Association & ASPAN. Recognition, Evaluation and Control of Waste Anesthetic Gases in the Post-Anesthesia Care Unit. AIHA & ASPAN. 2021

      These anesthetic gases are currently removed from the operating rooms through closed systems and generally are ventilated into the environment off of the roof of the hospital. These agents are greenhouse gases with nitrous oxide having an atmospheric life of 114 years, and Desflurane containing a chlorine molecule that contributes to ozone depletion.
      • Sherman J.
      • Le C.
      • Lamers V.
      • Eckelman M.
      Life cycle greenhouse gas emissions of anesthetic drugs.
      ,
      • Varughese S.
      • Ahmed R.
      Environmental and occupational considerations of anesthesia: A narrative review and update.
      The United States healthcare system generated 8% to 10% of the total emissions of greenhouse gases for our nation, while the United Kingdom's national healthcare system generated 25% of the nation's public sector emissions.
      • Badgwell J.M.
      The postanesthesia care unit: A high-risk environment for bloodborne and infectious respiratory pathogens.
      ,
      • Sapuan S.M.
      • Ilyas R.A.
      • Asyraf M.R.M.
      Carbon footprint in healthcare.
      While health care can heal, it is also making our environment ill.

      A Call for Action

      To reduce perianesthesia nurses’ occupational exposure to WAGs, engineering controls must be implemented to reduce exposure or remove the hazard (Figure 1). The ASPAN WAGs Position Statement, supported by AIHA, recommends engineering controls for the source of WAGs in the PACU, with the source being the immediate post procedure general anesthesia patient. Scavenging masks placed on the patients as soon as they enter the PACU can reduce the amount of WAGs and pathogens these patients exhale. These scavenging masks can reduce occupational exposure of perianesthesia nurses and other patients that were intentionally not given anesthetic gases due to health risk factors.

      American Industrial Hygiene Association & ASPAN. Recognition, Evaluation and Control of Waste Anesthetic Gases in the Post-Anesthesia Care Unit. AIHA & ASPAN. 2021

      Perianesthesia nurses should share the AIHA & ASPAN whitepaper with their leadership to increase awareness and requests compliance with the recommendations in the ASPAN Position Statement. These important documents are available on ASPAN's website along with a link to view the recording of ASPAN's Special WAGs event held August 2021. Share the link to these resources with coworkers, colleagues, and leadership. It can be found at ASPAN's website (https://www.aspan.org/Publications-Resources/White-Papers) All nurses should advocate for a healthy environment for perianesthesia nurses and the patients and families we care for.
      Figure 1
      Figure 1Hierarchy of controls, reprinted with permission from the National Institute of Occupational Safety& Health (NIOSH). This figure is available in color online at www.jopan.org. https://www.cdc.gov/niosh/topics/hierarchy/default.html.

      References

      1. World Health Organization. State of the world's nursing report 2020: investing in education, jobs and leadership. 2020. Accessed November 22, 2022. https://www-who-int.proxy.library.vanderbilt.edu/publications/i/item/9789240003279

        • Kharasch ED
        Biotransformation of sevoflurane.
        Anesth Analg. 1995; 81: 27S-38S
        • Sherman J.
        • Le C.
        • Lamers V.
        • Eckelman M.
        Life cycle greenhouse gas emissions of anesthetic drugs.
        Anesth Analg. 2012; 114: 1086-1090
        • Vaisman A.I.
        Working conditions in surgery and their effect on the health of anesthesiologists.
        Ekspkhiranesteziol. 1967; 3: 44-49
      2. American Industrial Hygiene Association & ASPAN. Recognition, Evaluation and Control of Waste Anesthetic Gases in the Post-Anesthesia Care Unit. AIHA & ASPAN. 2021

      3. Centers for Disease Control and Prevention. Criteria for a recommended standard: Occupational exposure to waste anesthetic gases and vapors. 1977 National Institute for Occupational Safety and Health. Retrieved November 18, 2022, from https://www.cdc.gov/niosh/docs/77-140/default.html

        • Badgwell J.M.
        The postanesthesia care unit: A high-risk environment for bloodborne and infectious respiratory pathogens.
        J Perianesth Nurs. 1996; 11: 66-70
        • Varughese S.
        • Ahmed R.
        Environmental and occupational considerations of anesthesia: A narrative review and update.
        Anesth Analg. 2021; 133: 826
        • Sapuan S.M.
        • Ilyas R.A.
        • Asyraf M.R.M.
        Carbon footprint in healthcare.
        Safety and Health in Composite Industry. Springer, Singapore2022: 115-137