{
  "abstract": "The Greenest Block Vivian H. Y. Ip MBChB FRCA Clinical Professor, Department of Anesthesia, Perioperative, and Pain Medicine South Health Campus University of Calgary Calgary Alberta Canada Email: hip@ualberta.ca Conflict of Interests: Dr. Vivian Ip is the Chair of the Environmental Sustainability Section, the Chair of the Regional Anesthesia Section at the Canadian Anesthesiologists’ Society, and the Chair of the Green Anesthesia Special Interests Group at the American Society of Regional Anesthesia and Pain Medicine. Word count = 1516 References = 24   Introduction Healthcare contributes to 4.6% of the net global carbon dioxide emission 1 and the statistics provided by the ‘United Nations Environment Program’ where to limit the global temperature rise to 1.5° C (34.7° F), carbon emissions must decrease by 42% by 2030 and by 57% by 2035.2 Limiting global temperature risk is crucial to prevent adverse impact on our ecosystem and species.3 For example, the temperature of the beach sand that female sea turtles nest in influences the gender of their offspring during incubation, the warming climate may be driving sea turtles into extinction by creating a shortage of males.4 The extremes and frequency of the intense weather events, such as uncontrollable wildfire, drought, deadly heatwave, flooding will be 150 times less likely if the global warming is contained below the 1.5 degrees Celsius threshold.5 As healthcare providers, it is our professional duties to first do no harm and reflect on our clinical practice to be good steward in environmental sustainability, as there is a significant negative impact from climate change on the health and livelihood of humanity.6 The objective of this abstract is to recognize the potential for regional anesthesia to be environmentally sustainable, however, resource utilization is a key component to achieving a truly ‘green’ regional anesthesia technique. The goal is to balance the reduction of carbon footprint and waste generation while maintaining patient safety. Key aspects of the ‘Greenest’ block Reduction of waste, energy efficiency, environmentally responsible medication use, as well as waste segregation and proper waste disposal are the key components in practicing the ‘greenest’ block. Reduction of waste Reducing waste require a conscious effort to use only the necessary supplies and equipment during clinical practice to reduce waste, especially the requirement of aseptic techniques, sterility and equipment packaging. Using reusable attires and equipment is the first step towards disposable waste reduction. Many life cycle assessments have demonstrated the reduction in carbon dioxide emission despite the energy used for processing reusable attires and equipment such as drapes, caps.7–10 It was previously thought that premade pack would be more environmentally sustainable, however, it depends on the method used to produce the pre-made pack. The premade pack should contain minimal equipment common to the group of practitioners.11 Furthermore, the manufacturing process and transportation of the items within the pack can affect the carbon emission, e.g., the material is produced within the facilities where the premade packs are made which omits the packaging of each material versus the manufacturers obtained packaged material requiring transportation and packaging for the items within the pack.12 Guided by evidence, only use items that are necessary for performing the nerve block, and forego the practice that are not rooted in evidence, e.g., the requirement of gown. The evidence for gowning during regional procedure is not robust, even for indwelling catheters that are 4 days or less.13 Previous observation study showed the energy used to process reusable gowns increases the carbon footprint as one of the reasons to explain the carbon emission for spinal anesthesia is disproportionately higher than that for a general anesthetic.14 Therefore, clinical decision of the duration of indwelling catheter (epidural or peripheral nerve blocks), is part of the consideration for environmental sustainability practice. Strategies for reducing waste also includes doing more with less. Hand hygiene is rooted in evidence to reduce infection.15 Alcohol-based hand rub for use in between patients will reduce resource use and waste generation when compared to hand wash with soap and water, with the need to dry them with towels, unless they are visibly soiled.15 16 The same principle applies with the use of aseptic non-touch technique which is a clinical guideline incorporated into many protocols within institutions globally. Table 1 shows the practice parameters that achieved strong consensus (>=75% agreement) in the Delphi consensus study11 for the environmentally responsible use of resources during regional anesthesia. (Table 1) Energy efficiency Ineffective energy used has been demonstrated by the Canadian Coalition for Green Healthcare of up to 80% energy consumption by imaging devices when not scanning.17 The observation study quantifying the savings on energy consumption by switching ultrasound machine between uses also demonstrated 80% savings, as well as 100 CAD annual savings per ultrasound machine. The cumulative savings for the province of Alberta in Canada with 400 ultrasound machines are approximately 40,000 CAD per year.18 Previous theoretical calculation of electricity use and associated carbon emission showed that failing to turn off the ultrasound machine between uses require additional ‘plug-in’ time to replenish lost charge, which leads to wasted electricity in real-time, and the inability of battery to hold a charge long term, further increasing required ‘plug-in’ time. This process subsequently results in premature disposal and replacement of battery for the ultrasound machine.19 Environment Many institutions have a separate area (block room) where regional techniques are performed prior to the patients entering the operating room. If this is the case, the temperature of the block room can be set to a comfortable temperature. Other measures which require support from facility managers are to change the light to LED lighting, or sensors-activated lighting such that the light are not switched on during after hours. Switching the computers off, as well as the ultrasound machines as aforementioned will reduce unnecessary electricity and energy consumption. Medication use, waste and disposal Refrain from preparing excessive number of local anesthetic syringes which will be wasted at the end of the day, or work with pharmacy for pre-filled local anesthetic syringes. For oxygen and sedation, goal-directed therapy titrated to individual needs will prevent overuse of oxygen. A previous observation study found the carbon dioxide emission is similar for all types of anesthetic due to the overuse of oxygen at 10 L/min.14 Clinically, if oxygen consumption is increasing, perhaps consider reducing the amount of sedation or use an alternative method for sedation, e.g., music.20 Despite oxygen being abundant in the atmosphere, electricity is required to compress oxygen into liquid oxygen for medical use via cryogenic distillation which produces global warming potential of 0.49 kg carbon dioxide equivalent per bed day, assuming 2 L/min use.21 When oxygen is supplied to hospital in a cylinder format, there will be a substantial increase in environmental impacts from additional container and transportation.21 Contaminants of emerging concern comprise different contaminants, including pharmaceuticals with potential threat to the environment and public health.22 Therefore, proper disposal of medication is important to prevent water contamination or accumulation in the soil. There are commercially available drug destruction bags or containers which will be incinerated, as well as disposal through the pharmacy department. When choosing between multi-dose and single-use medication vials, patient safety is paramount. Centers for disease control and prevention has warned against misuse of multi-dose vials with outbreaks of 56% bacterial infections and 44% viral hepatitis, despite the presence of antimicrobial preservative in multi-dose vials to help limit the growth of bacteria, which has no effect on blood borne viruses.23 Despite potential reduction in solid waste from using multi-vial medications as it can be used for more than 1 patient when aseptic technique is followed,23 very often, the amount of drug waste may be higher than a single-use vials although there is a lack of data in this area. Waste Disposal While proper waste segregation and recycling are important, recycling is low yield, especially in healthcare as most materials are assumed to be contaminated and would either be sent to the landfill, or incineration. Therefore, it is crucial to eliminate wasteful and redundant practice, and opt for reusable supplies whenever possible, while balancing patient safety. Furthermore, even when items are collected for recycling, they are expensive to recycle with a lack of facilities to process the items to reprocess them into valuable products for use.24 Framework of ‘Green-gional anesthesia’ The basic requirement is systematic reduction to minimize waste while maintaining patient safety. There needs to be a balance between practice standards while balancing realistic goals for infection prevention and patient safety. Measures should be evidence-based, rather than expert-opinion consensus. This is especially relevant given that rates of infection are very low. While infection prevention remains critical, there comes a point where excessive resource allocation no longer yields clinically significant benefits. In fact, unnecessary waste can ultimately harm society and the humanity. Therefore, healthcare practices should be evaluated through a sustainability lens, and guided by current evidence. Mindful stewardship means resource consciousness should incorporated as a routine practice with every procedure. This not only reduce environmental impact of our clinical practice and healthcare contribution to the carbon dioxide emissions, these initiatives also save costs. The top rung is to achieve the triple bottom line of optimizing planet, people and profit. Conclusion The Greenest block is also the safest for patients as patient safety always remain the absolute non-negotiable priority in all green initiative. The greenest block is to re-evaluate our practice through both the evidence-based, and environmental sustainability lens to only use resources that are necessary and based on evidence for infection prevention. This mindful stewardship should be embedded into routine practice and data collection is encouraged. The greenest block is precise, efficient, and effective for both patient and planet – which ultimate means the humanity.Abstract FT24 Table 1Table showing the practice parameters with strong consensus for different types of nerve block techniques (Ip) Types of regional anesthesia techniques Attire Setup Single shot spinal Scrub capMaskHand sanitize with alcohol rubSterile glovesNo sterile gownClean site with antimicrobial skin preparationSterile drape Premade pack can be used if it contains minimal equipment common to the groupNo US probe cover for pre-scanFull sleeve US probe cover for real-time needling Epidural catheter Scrub capMaskHand sanitize with alcohol rubClean site with antimicrobial skin preparationSterile drapePremade pack can be used if it contains minimal equipment common to the groupPremade pack can be used as a sterile workspaceNo US probe cover for pre-scanFull sleeve US probe cover for real-time needling rather than the plastic film cover Single shot nerve block Hand Sanitize with alcohol rubClean site with antimicrobial skin preparationSterile drape and tray are not requiredPremade pack can be used if it contains minimal equipment common to the groupAseptic non-touch technique can be use if done properlyNo US probe cover for pre-scan Nerve block catheter – traditional catheter-through-needle Scrub capMaskHand sanitize with alcohol rubSterile glovesSterile gownClean site with antimicrobial skin preparationSterile drapePremade pack can be used if it contains minimal equipment common to the groupNo US probe cover for pre-scanFull sleeve US probe cover for real-time needling Nerve block catheter – Catheter-over-needle Scrub capMaskHand sanitize with alcohol rubSterile glovesClean site with antimicrobial skin preparationSterile drapePremade pack can be used if it contains minimal equipment common to the groupNo US probe cover for pre-scanFull sleeve US probe cover for real-time needlingReferences The Lancet Digital Health. 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  "authors": [
    {
      "affiliations": [
        "Anesthesia, University of Calgary, Calgary, Canada"
      ],
      "name": "Vivian Ip"
    }
  ],
  "title": "FT24 The greenest block",
  "uid": "b14ec688-ceb8-5917-af3f-f4d6d6f9c8b8"
}