Choosing Wisely & Climate Action

Don’t use desflurane when other anesthetic drugs and techniques are equally effective and less harmful to the environment. 

Anesthetic gases possess significant global warming potential (GWP) and contribute approximately 5% of the harmful greenhouse gas emissions of a typical hospital. However, not all anesthetic gases are equally harmful. The anesthetic gas desflurane has the highest GWP at twenty times more than that of sevoflurane. In addition, when both are delivered at equal fresh gas flows, desflurane has approximately 50 times the impact of sevoflurane due to its lower potency. Patient care can be provided safely and efficiently without desflurane; anesthetic alternatives such as sevoflurane, intravenous anesthesia or regional techniques should be considered, depending on clinical and geographical context. The restriction of the use of desflurane is supported by the Canadian Anesthesia Society, American Society of Anesthesiologists and World Federation of Societies of Anaesthesiologists.

The elimination of desflurane is an effective change that aligns with the Choosing Wisely environmental practice recommendations. Recommendation #6.

Don’t exclusively offer centre-based cardiac rehabilitation when home-based cardiac rehabilitation programs can be offered for adults with myocardial infarction, angina, heart failure or those who have undergone revascularisation. 

Cardiac rehabilitation is crucial in the treatment of patients living with cardiovascular disease. These structured programs improve the physical, psychological, and social well-being of individuals with specific conditions or following a cardiovascular event or procedure. They are typically delivered on-site and include supervised exercise training, education on heart-healthy behaviors, nutritional guidance, stress management techniques, and psychosocial support. The development and evaluation of in-home programs with or without the use of digital support have been compared with centre-based rehabilitation in a recent systematic review that assessed a total of 24 trials and included a total of 3046 participants. No evidence of a difference was seen between home- and centre-based cardiac rehabilitation in terms of total mortality, exercise capacity or in health-related quality of life. We can therefore offer an alternate effective model of programming in appropriate patients in their home environments and limit travel.

Centre-based cardiac programs vary in terms of travel distance for patients, frequency, and duration. It is estimated that home-based program could reduce the need for trips to on-site facilities by 50-75%. Driving contributes significantly to Canada’s carbon footprint, with transportation being one of the largest sources of greenhouse gas emissions in the country. Addressing transportation-related emissions, including those associated with driving to healthcare facilities, is crucial for mitigating climate change. Recommendation #8.

Clinicians play an important role in reducing environmental impact from clinical laboratory activity. The production, transportation and disposal of laboratory products have an environmental impact which includes, but is not limited to: tourniquets, needles, tubes, labels, and plastic specimen collection bags. Within the laboratory, additional waste is generated from the specimens, reagents and materials used for testing. The large amounts of energy and water consumed to generate results has a significant carbon footprint as well. Moreover, spurious results frequently lead to unnecessary medical follow-up or misguided therapy with further waste of resources and extension of the carbon footprint. Reducing blood work frequency (as appropriate), reflecting on appropriateness of laboratory orders (Using Labs Wisely) and rethinking laboratory orders (checking previous results instead of reordering, limiting duplication) are potential strategies to reduce environmental impact. Recommendation #11.

Don’t purchase laboratory equipment and/or supplies without consideration of environmental impact while maintaining diagnostic proficiency.

Laboratory testing contributes to a significant carbon footprint due to the required infrastructure (i.e. electricity, HVAC, water) and generated waste (i.e. biohazardous waste, plastic consumables). For example, a laboratory with 10 automated analyzers can consume enough water to fill an Olympic-sized pool annually. This is especially relevant as laboratories move towards increased automation and expanding test menus with a constant focus on throughput and turnaround time. While individual laboratories have agency on some of the contributing factors, the carbon footprint of laboratory testing is largely determined by the inherent design of the instrumentation. As such, it is vital that laboratories establish partnerships with the in vitro diagnostics industry to push for material, hardware, and software changes that allow for laboratory testing in an environmentally sustainable manner. There is a growing international movement in sustainable laboratory medicine with some associations already having published formal guidance in this space. Recommendation #12.

Don’t use gloves when hand hygiene is sufficient.

Gloves don’t need to be used for most routine healthcare interactions with certain exceptions. Unnecessary use of gloves is common, leads to increased costs, generates waste and may inadvertently increase rates of cross-contamination. A study in the Netherlands found that >100 disposable gloves were used in the ICU per patient per day contributing to the highest carbon footprint compared to other commonly used products. Recommendation #6.

Don’t change ventilator tubing or in-line suction catheters unless they are visibly soiled.

Less frequent ventilator tubing or in-line suction catheter changes have been shown to result in equal or lower rates of ventilator-associated pneumonia. Current guidelines suggest circuit changes on an as needed basis rather than a more frequent or fixed replacement schedule. Recommendation #7.

Don’t bring surplus supplies or equipment into patient care rooms if they will require disposal after patient transfer/discharge.

Disposal of unused medical supplies is common in ICUs, particularly at the time of patient transfer. Practices such as centralized supply carts, as-needed in-room restocking, and keeping emergency medication immediately available but unopened, have been suggested to minimize waste generated from unused items. Recommendation #8.

Don’t continue intravenous medications when an oral/enteral alternative is equally safe and effective.

Intravenous medication administration requires additional equipment including syringes, IV tubing, and/or IV bags, may increase the carbon footprint and negatively affect planetary health, as compared to enteral administration. Intravenous antibiotics have been found to have 10-70 times greater carbon footprint than the equivalent oral form. Several medications may be equally safe and effective when administered enterally including antimicrobials, gastric acid suppressing medications, anti-epileptic medications and pain medications. Recommendation #9.

Don’t use single-use/disposable items when a reusable option is available and less resource intensive.

Several studies have found decreased overall environmental costs with reusable equipment as compared to single-use disposable equipment (McGain & McAlister, 2023). Some examples relevant to critical care include laryngoscopy handles and blades (Sherman et al., 2018), blood pressure cuffs (Sanchez, et al., 2020), pulse oximeters (Duffy et al., 2023) and sterile surgical/procedural gowns and drapes (Overcash, 2012). The benefit however is not universal for all equipment or ICUs and depends on local practices and hospital electricity source and sterilization practices (McGain et al., 2012). Recommendation #10.

Don’t continue patient isolation precautions (e.g. shield, gown, gloves) at the earliest safe opportunity in keeping with institutional Infection Prevention & Control.

Supplies used for isolation precautions contribute to waste generated in ICUs. Eliminating no longer necessary isolation/infectious precautions reduces this waste and consequently the carbon footprint of ICUs. Recommendation #11.

Don’t transfer a patient out of ICU without completing a medication reconciliation and deprescribing ICU-specific medications that are no longer indicated.

Continuing unnecessary medications after a patient’s ICU stay exposes them to risks and contributes to an increased carbon footprint and waste generation. Medications make up a significant contribution to the carbon footprint of healthcare in general, and in the ICU. Recommendation #12.

Don’t conduct in-person visits where virtual assessment would provide equivalent clinical value and is preferred by the patient.
Note: This recommendation applies where fee structures exist to compensate for virtual care.

Remote monitoring of chronic conditions (for example, to detect early signs of deterioration, to deliver education, to deliver cognitive behavioral therapy) has been found to be safe and effective. A systematic review found no difference in heart failure mortality or hospitalizations and a small improvement in quality of life with virtual care. Blood pressure control was slightly better with virtual monitoring. Effect of therapy for people with mental health and substance abuse problems showed no difference compared to face-to-face delivery. Inflammatory bowel disease monitored by telemedicine showed no difference in flare-ups, quality of life or surgeries.

Uncomplicated urinary tract infections can be diagnosed and treated on the basis of history alone, without additional urine testing. Due to limited evidence supporting evaluation/diagnosis of undifferentiated problems, this recommendation does not apply for most diagnostic consultations.

Travel to and from health facilities by patients, visitors and staff accounted for 10% of the UK NHS emissions. Recommendation #14.

Don’t conduct in-person visits for GI care when a virtual visit can be performed and is clinically appropriate (for example – routine follow-up visit, post-endoscopy review of normal biopsy results, etc.,) and is preferred by the patient.

There is an increasing volume of literature which shows that delivery of health care in digestive health by telemedicine can be safe and effective.

Driving is one of the activities with a high carbon footprint. Cars emit an average of 206g of CO2e per kilometer. To put this in context a mature tree metabolizes about 20 kg of CO2 per year, the equivalent of driving less than 100km. Travel to and from health facilities by patients, visitors and staff accounted for 10% of the UK NHS emissions. Travel is a significant contributor to health care emissions.

In a cross-sectional study of more than 10 million patients and 63 million virtual care visits, virtual care was associated with avoidance of 3.2 billion km of patient travel, 545 to 658 million kg of carbon dioxide emissions, and $569 to $733 million (Canadian [US $465-$599 million]) in expenses for gasoline, parking, or public transit. Recommendation #12.

Don’t routinely open all case cart items unless they are or become necessary to the procedure.

Operating room waste accounts for approximately 70% of all hospital waste. Not opening case cart items unless they are necessary to the procedure reduces the amount of opened and unused material, thereby reducing surgical waste. This conserves energy by diminishing the need for energy-intensive waste disposal and sterilization methods. Additionally, surgical waste reduction also mitigates the production of pollutants and greenhouse gases that result from the disposal and sterilization of surgical waste. Recommendation #8.

Don’t replace fillings unless they have failed.

Dental restorations (fillings) fail due to excessive wear, fracture of material or tooth, loss of retention, or recurrent decay. Drilling to remove and replace fillings can weaken teeth and decrease their lifespan. Small defects should be repaired. Age of a filling should never be used as criteria for replacement.

Dental amalgam is a safe, affordable and effective dental material. Removal of amalgams, if the restoration is otherwise sound or can be repaired, is unnecessary, expensive, and may subject the individual to absorption of small doses of mercury. Furthermore, placement of composite resin restorations is known to cause a transient increase in urinary Bisphenol-A levels, for which there are unknown health effects. High-quality evidence suggests higher failure rates in composite resins versus amalgam restorations.

A preventive approach to the management of dental decay and a focus on long-lasting conservative restorations when they are truly indicated allows dental care to be delivered in a more environmentally sustainable way. Dental materials have an impact on the environment through all phases of manufacturing, procurement, clinical use and waste disposal. Use of rubber dam, high volume suction and mandated separation of amalgam waste contribute to both patient safety and planetary health. Recommendation #5.

Don’t provide in-person care when a virtual care visit can address the patient’s problem effectively and is acceptable to the patient, for example, to relay negative oral biopsy results or when frailty or distance prevents travel to a dental assessment.

Virtual care minimizes exposure of vulnerable patients to incidental infections and allows patients to avoid unnecessary travel. It provides more timely and accessible care, especially when challenges such as distance, disability, or frailty exist. A co-benefit of virtual care is planetary health. Patient, provider, and staff travel to and from dental appointments accounts for the largest percentage of total carbon emissions in the dental clinic setting. Travel for dental appointments can be reduced by combining visits for family members, combining operative procedures, reducing appointment frequency based on patient risk and the use of virtual care when appropriate. Recommendation #7.

Don’t prescribe greenhouse gas-intensive metered-dose inhalers (MDIs) for asthma and/or COPD where an alternative inhaler with a lower carbon footprint (e.g. dry powder inhaler (DPI), soft-mist inhaler, or MDI with a low greenhouse gas potential propellant) containing medications with comparable efficacy is available, and where the patient has demonstrated adequate technique and patient preference has been considered.

Before prescribing or recommending inhalers, providers should ensure a confirmed objective diagnosis of asthma and/ or COPD exists to reduce unnecessary inhaler use and patient exposure. When inhalers are indicated, consider patient-specific factors and preferences to determine if lower carbon intensive inhaler device(s) (Dry Powder Inhalers (DPIs), or soft-mist inhalers (SMIs)) is clinically appropriate as both are often preferred by patients and are as effective as MDIs. Once a device has been selected, ensure the patient is trained on proper inhaler device technique, and technique is reviewed intermittently, as inhaler education programs have shown to reduce exacerbation rates. Additionally, non-pharmacologic strategies (e.g. education, trigger avoidance, action plans) should also be included in airway management, as they not only improve patient outcomes, but can also reduce rescue inhaler use.

MDIs which contain hydrofluoroalkane (HFA) propellants known to contribute to climate change, account for 0.03% of global gas emissions annually. Thus prescribing low carbon footprint inhalers when medically indicated, ensuring adequate patient inhaler technique and incorporating nonpharmacologic strategies into airway management, can lead to better patient outcomes with environmental co-benefits. Recommendation #7.

Don’t start or continue medications without an indication or where the risks outweigh the benefits.

Optimizing medication usage yields positive clinical outcomes for patients. In 2021, 25% of Canadian older adults were prescribed 10 or more medication classes, leading to polypharmacy and increased healthcare costs, adverse reactions, and potential interactions. Re-evaluating prescriptions to discontinue unnecessary medications can reduce adverse events, healthcare burdens, and enhance quality of patient care. Addressing polypharmacy enhances individual and healthcare system efficiency and sustainability. Furthermore, optimizing medication use reduces pharmaceutical waste and environmental impact. Close to 100000 million tonnes of CO2 emissions are released from unused medications and pharmaceutical waste every year. Medications account for a quarter of carbon emissions within the healthcare sector. By avoiding the prescribing of unnecessary or unindicated prescriptions healthcare providers may contribute to reducing the overall demand for raw materials and energy-intensive processes involved in pharmaceutical production. Recommendation #8.

Don’t pour any pharmaceuticals or chemicals down sinks, toilets, or drains or dispose of in the trash.

Ensuring proper medication disposal is crucial to minimize health risks, preventing misuse and adverse effects. Less than 1% of patients return unused medication, increasing the likelihood of accidental ingestion by children and pets. Flushing medications down the toilet, a prevalent disposal method, poses risks of antibiotic resistance and water contamination. The improper disposal introduces pharmaceutical residue into water systems, threatening aquatic life. Education on safe disposal and encouraging return to designated collection sites can reduce these risks. Regulatory measures, such as those implemented in British Columbia, aim to address pharmaceutical waste through recycling regulations, highlighting the importance of comprehensive strategies to minimize environmental harm. Recommendation #9.

Don’t print prescription or educational materials when providers and patients have access to digital communication.

Reducing paper usage has been shown to minimize the risk of prescription errors. Decreasing paper prevents waste and recycling needs, hence is environmentally beneficial. Recommendation #10.

Don’t use disposable gloves when standard hand hygiene disinfection practices are safe and sufficient.

In pharmacy settings, when the risk of body fluids exposure and infection transmission is low, maintaining safety standards in most routine healthcare interactions can most often be achieved by using proper hand hygiene without additional precautions. Do not use gloves in place of hand hygiene or when hand hygiene alone is sufficient. The pharmacy staff should reserve the use of gloves to situations in which the safeguard of pharmacy staff is required due to risk of infection, or to comply with infection prevention and control (IPAC) and National Association of Pharmacy Regulatory Authorities (NAPRA) standards and/or guidelines. Refraining from using latex or nitrile gloves when not medically necessary is an important aspect of environmental stewardship to be considered by healthcare professionals. Minimizing the use of gloves can help reduce environmental waste associated with disposable medical supplies, contributing to sustainability efforts in healthcare facilities. Approximately 500 boxes of gloves were found to emit 2 tonnes of CO2 emissions. Limiting the use of gloves is highly effective in promoting environmental sustainability. Recommendation #11.

Don’t continue an intravenous medication when clinically appropriate to step down to oral therapy.

While intravenous (IV) may be required for patients who do not or cannot tolerate oral therapy or for certain medical conditions or medications, IV therapy is associated with several complications.  These include: phlebitis, thrombophlebitis, infiltration, extravasation, and catheter-related infections and bacteremia infections, hematoma, thrombosis, pain or discomfort, and fluid overload in fluid-restricted patients, such as some patients with renal or cardiac disease. Switching to oral therapy, when and if clinically appropriate, has other potential benefits for the patient including:  increased ease of mobility, better quality of life (some patients feel less “medicalized”), earlier discharge from the hospital, thereby decreasing the risk of hospital-acquired infections.  Other benefits include reduced length of stay, rate of hospital-acquired infections, lower drug costs and reduced waste (eg. Tubing, expired IV bags).

Although the life cycle analyses of most medications are not widely available, the carbon footprint of intravenous medications is estimated to be higher than oral medications due to primary packaging materials, plastic waste, equipment for administration and their disposal. Switching from IV to oral therapy reduces length of hospital stay and may reduce its associated environmental impacts. Recommendation #12.

Don’t use desflurane when other anesthetic drugs and techniques are equally effective and less harmful to the environment.

Anesthetic gases possess significant global warming potential (GWP) and contribute approximately 5% of the harmful greenhouse gas emissions of a typical hospital. However, not all anesthetic gases are equally harmful. The anesthetic gas desflurane has the highest GWP at twenty times more than that of sevoflurane. In addition, when both are delivered at equal fresh gas flows, desflurane has approximately 50 times the impact of sevoflurane due to its lower potency. Patient care can be provided safely and efficiently without desflurane; anesthetic alternatives such as sevoflurane, intravenous anesthesia or regional techniques should be considered, depending on clinical and geographical context. The restriction of the use of desflurane is supported by the Canadian Anesthesia Society, American Society of Anesthesiologists and World Federation of Societies of Anaesthesiologists. The elimination of desflurane is an effective change that aligns with the Choosing Wisely environmental practice recommendations. Recommendation #13.

Don’t discard medications that are appropriate for re-dispense.

Considerable pharmaceutical waste is generated in hospital settings which can be reduced by appropriately re-dispensing unused medications. A study from three Fraser Health hospitals extrapolated the results to show re-dispensing unused oral solid medications in 21 hospitals could divert ~ 461 000 units of medication from the incinerator with an estimated net value of ~ 415 000 per year. Re-dispensing unused medications will decrease environmental impact associated with unnecessary drug wastage (disposal/incineration). Recommendation #14.

Don’t continue medications upon hospital transitions (admission, transfers, and discharge) unless there is a clinical indication.

The continuation of unnecessary medications can lead to potential adverse effects and increase consumption and costs to the patient. The performance of medication reviews at transitions of care within hospitals has been shown to decrease adverse drug event-related hospital revisits, emergency department (ED) visits and hospital readmissions. One study estimated that avoiding in-hospital activity and journeys to and from hospital resulted in a reduction in avoidable medicine-related admissions of 110 tonnes of greenhouse gas emissions, 179 million m3 of fresh water and 13, 300 tonnes of waste. Thus, performing medication reviews throughout a hospital stay and optimizing medications may help reduce the overall use and consumption of health care resources and impacts to the environment. Recommendation #15.

Don’t make formulary decisions, without consideration of environmental impact.

Embedding a planetary health lens when making pharmacy system-level decisions, benefits the health of the population by reducing the associated adverse health impacts. Selecting medications with lower environmental impact to be added to hospital formularies, adopting green purchasing strategies (such as streamline ordering and delivery of medications to reduce carbon emissions) and ensuring medicine procurement policies incorporate and where possible prioritize manufactures, supplier and distributors with commitments to sustainability are a few examples of embedding planetary health lens in pharmacy system-level decisions. Recommendation #16.

Don’t prescribe intravenous (IV) antibiotics for patients who can safely be treated with an oral option, given that IV antibiotics have a higher carbon footprint.

There is emerging evidence that conditions traditionally treated with prolonged courses of IV antibiotics, such as osteomyelitis or infective endocarditis, can safely be treated with PO antibiotics after a lead in period of IV therapy. Studies from the UK estimated that oral antibiotics have a carbon footprint up to 90% lower than the IV equivalent, depending on the antibiotic – a one-week course of oral ciprofloxacin is associated with 1.4kg CO2e (6.8km by car) of emissions versus 100.1kg CO2e (485.9km by car) for intravenous ciprofloxacin. The same group ran an early oral antimicrobial step-down project which saved 300,000 British pounds (or ~$450,000 CAD) annually. Among patients on IV antibiotics, early transition to oral antibiotics has the additional co-benefits of reducing hospital length of stay, length of treatment, nursing care needs, in addition to lowering carbon footprint.

a) All kgCO2e to km conversions in these recommendations are based on a carbon footprint conversion factor of 206gCO2e/km for the average Canadian vehicle in 2017. From: International Energy Agency. Fuel Economy in Major Car Markets: Technology and Policy Drivers 2005-2017. March 2019. Recommendation #12.

Don’t prescribe heparin or low molecular weight heparin in situations where oral options are effective, preferred by the patient, and felt to be safe by the prescriber.

Specialty societies support the use of oral anticoagulation as initial therapy for many disease states. Evidence also suggests that patients prefer oral anticoagulants over subcutaneous formulations (most commonly, heparinoids) as the oral route is considered easier, less painful and less expensive. Heparinoids are also a highly carbon-intensive medication. The only Health Canada approved source of heparin is porcine mucosa; heparin cannot be synthesized artificially. Approximately 1.1 billion pigs are raised each year to meet the worldwide demand for heparin. It is estimated that 1 kg of intestinal mucosa will produce 160–260 mg of crude heparin. The carbon footprint of raising a heparin swine to maturity is 6.1kg CO2e (30km by car) per kg of pig which amounts to 668 million tonnes CO2e annually (over 3 trillion km by car). Heparin swine are raised in tightly regulated and highly specific conditions with regards to antibiotic and growth hormone usage and cannot be used for dietary pork consumption. The environmental impact associated with processing, manufacturing, transport, and packaging is unpublished but add to heparin’s substantive carbon footprint. Recommendation #13.

Don’t prescribe greenhouse gas-intensive metered-dose inhalers (MDIs) where a lower carbon alternative with comparable efficacy is available (e.g. dried-powder inhaler, soft-mist inhaler, or low-propellant MDI) in situations where technique is adequate and where patient preference has been considered.

MDIs contain hydrofluoroalkane, a potent greenhouse gas that expels the active ingredient from the inhaler device. Based on the type and volume of propellant used, an MDI produces between 9.7kg CO2e (47.1km by car) and 34.8kg CO2e (168.9 km by car). Dried powder inhalers (DPIs) and soft-mist inhalers (SMIs) lack propellant and are significantly less carbon intensive (<1kg CO2e or 5 km by car). Patients consider the environmental impact of their device to be an important consideration when choosing an inhaler device. Recommendation #14.

Don’t recommend/order investigations or interventions before discussing patients’ expected trajectory of health and life expectancy, and exploring their preferences, values and goals of care.

Interventions that do not align with patient goals produce needless environmental impacts. Ensuring that care setting aligns with a patient’s goals of care can have an important impact on the carbon footprint of a hospital admission. An acute care unit (ward bed) generates 5.5kg of solid waste and 45kg CO2e (218 km by car) per hospital day, as compared to 7.1kg of solid waste and 138 kg CO2e (670 km by car) in an intensive care unit. By integrating routine cognitive and frailty screening for older patients (a low carbon, high value clinical intervention), internists can unmask dementia and discuss the risks of frailty with patients and caregivers which leads to more patients choosing conservative care better aligned with their prognosis and goals, and stands to reduce acute care days. Recommendation #15.

Don’t continue medications without confirming appropriate clinical indications, with particular attention paid to sedative medications, proton pump inhibitors and inhalers.

Prescription and non-prescription medications are responsible for 25% of the carbon emissions of Canadian healthcare, related mostly to the environmental impact of supply chain and distribution. Polypharmacy and the excess prescribing are prevalent and harmful, particularly for older adults with numerous comorbidities. The highest risk medication classes that are often prescribed inappropriately are opioids, gabapentinoids, antipsychotics, sedative hypnotics, and PPIs. It has been shown to be safe and effective to deprescribe these medications at hospital discharge. Recommendation #16.

Don’t routinely order daily blood tests on hospitalized patients if it will not change management.

Running a CBC and electrolyte panel on a patient produces 0.3597kg CO2e (1.75km by car). Daily bloodwork seldom changes outcomes, exposes patients to harms (venipuncture associated pain, wake from sleep), and is associated with negative outcomes including anemia and need for transfusions. Routine and repetitive bloodwork can be safely discontinued through targeted interventions without increasing outcomes like re-admission, ICU admission, or mortality. Recommendation #17.

Don’t use non-sterile disposable gloves when hand hygiene is sufficient.

Gloves are unnecessary for most routine healthcare interactions and are usually not needed unless there is anticipated contact with blood, body fluids, secretions and excretions, mucous membranes, draining wounds or non-intact skin. A group in the UK calculated that on average, 107 non-sterile gloves are used per patient per day in the ICU, representing an excessive amount of unnecessary waste. With the carbon footprint of a single glove estimated to be 0.026kgCO2, that equates to 2.7kgCO2e per day (13.5km by car). Recommendation #18.

Don’t book in-person follow-up appointments when a virtual visit is clinically appropriate and is preferred by the patient.

Virtual care is a safe, effective, and environmentally friendlier alternative to traditional office visits in many chronic health conditions such as hypertension, diabetes, and frailty management/eldercare. In 2021, virtual care in Canada contributed to an estimated reduction of 330,000 metric tons of CO2. A study looking at the environmental impact of telemedicine in Ontario estimated that 185 159kg CO2e or 757 234km were avoided by conducting 840 appointments virtually over a 6-month period. Many provinces support equal remuneration between virtual and in-person care. Recommendation #19.

Do not utilize point-of-care testing where centralized labs can offer clinically acceptable turnaround reporting.

Point-of-care-testing (POCT) should be strategically utilized only in scenarios where it significantly influences immediate treatment decisions and offers a distinct advantage over traditional laboratory testing. Unlike laboratory-based tests, POCT may lead to more frequent false results potentially causing misdiagnoses, incorrect treatment decisions, and unnecessary additional testing or procedures contributing to further increased costs and medical waste. POCT’s reliance on single use, fossil-derived plastics, not only generates considerable waste but also poses environmental and health risks through potential toxic emissions from incineration. Recommendation #8.

Don’t continue intravenous (IV) medications when an oral or enteral alternative is equally safe and effective.

Administering medications intravenously requires additional equipment such as syringes, IV tubing, and IV bags, which significantly generates more waste compared to enteral routes. Research indicates that IV antibiotics have a greater carbon footprint than their oral counterparts. Many medications, including antimicrobials, gastric acid suppressants, anti-epileptic drugs, and pain relievers, are equally safe and effective when given enterally. Additionally, reducing IV administration can decrease the risk of IV-related complications, such as phlebitis, thrombophlebitis, infiltration, extravasation, catheter-related infections, hematoma, and thrombosis. Advocating for switching from IV to oral therapy, when clinically appropriate, benefits patients by increasing mobility, improving quality of life, and allowing for earlier discharge. This approach reduces hospital-acquired infections, length of stay, drug costs, and waste. Recommendation #10.

Don’t bring surplus supplies into patient care rooms if they will need to be disposed of after the patient is transferred or discharged.

Disposal of unused medical supplies is common during patient transfers. To minimize waste, suggested practices include centralized supply carts, as-needed room restocking, and keeping emergency medications available but unopened. Recommendation #11.

Don’t prescribe greenhouse gas-intensive metered-dose inhalers (MDIs) for asthma and/or COPD where an alternative inhaler with a lower carbon footprint (e.g. dry powder inhaler (DPI), soft-mist inhaler, or MDI with a low greenhouse gas potential propellant) containing medications with comparable efficacy is available, and where the patient has demonstrated adequate technique and patient preference has been considered.

Before prescribing or recommending inhalers, providers should ensure a confirmed objective diagnosis of asthma and/ or COPD exists to reduce unnecessary inhaler use and patient exposure. When inhalers are indicated, consider patient-specific factors and preferences to determine if lower carbon intensive inhaler device(s) (Dry Powder Inhalers (DPIs), or soft-mist inhalers (SMIs)) is clinically appropriate as both are often preferred by patients and are as effective as MDIs. Once a device has been selected, ensure the patient is trained on proper inhaler device technique, and technique is reviewed intermittently, as inhaler education programs have shown to reduce exacerbation rates. Additionally, non-pharmacologic strategies (e.g. education, trigger avoidance, action plans) should also be included in airway management, as they not only improve patient outcomes, but can also reduce rescue inhaler use.

MDIs which contain hydrofluoroalkane (HFA) propellants known to contribute to climate change, account for 0.03% of global gas emissions annually. Thus prescribing low carbon footprint inhalers when medically indicated, ensuring adequate patient inhaler technique and incorporating nonpharmacologic strategies into airway management, can lead to better patient outcomes with environmental co-benefits. Recommendation #7.

Don’t start or continue medications without an indication or where the risks outweigh the benefits.

Optimizing medication usage yields positive clinical outcomes for patients. In 2021, 25% of Canadian older adults were prescribed 10 or more medication classes, leading to polypharmacy and increased healthcare costs, adverse reactions, and potential interactions. Re-evaluating prescriptions to discontinue unnecessary medications can reduce adverse events, healthcare burdens, and enhance quality of patient care. Addressing polypharmacy enhances individual and healthcare system efficiency and sustainability. Furthermore, optimizing medication use reduces pharmaceutical waste and environmental impact. Close to 100000 million tonnes of CO2 emissions are released from unused medications and pharmaceutical waste every year. Medications account for a quarter of carbon emissions within the healthcare sector. By avoiding the prescribing of unnecessary or unindicated prescriptions healthcare providers may contribute to reducing the overall demand for raw materials and energy-intensive processes involved in pharmaceutical production. Recommendation #8.

Don’t pour any pharmaceuticals or chemicals down sinks, toilets, or drains or dispose of in the trash.

Ensuring proper medication disposal is crucial to minimize health risks, preventing misuse and adverse effects. Less than 1% of patients return unused medication, increasing the likelihood of accidental ingestion by children and pets. Flushing medications down the toilet, a prevalent disposal method, poses risks of antibiotic resistance and water contamination. The improper disposal introduces pharmaceutical residue into water systems, threatening aquatic life. Education on safe disposal and encouraging return to designated collection sites can reduce these risks. Regulatory measures, such as those implemented in British Columbia, aim to address pharmaceutical waste through recycling regulations, highlighting the importance of comprehensive strategies to minimize environmental harm. Recommendation #9.

Don’t print prescription or educational materials when providers and patients have access to digital communication.

Reducing paper usage has been shown to minimize the risk of prescription errors. Decreasing paper prevents waste and recycling needs, hence is environmentally beneficial. Recommendation #10.

Don’t use disposable gloves when standard hand hygiene disinfection practices are safe and sufficient.

In pharmacy settings, when the risk of body fluids exposure and infection transmission is low, maintaining safety standards in most routine healthcare interactions can most often be achieved by using proper hand hygiene without additional precautions. Do not use gloves in place of hand hygiene or when hand hygiene alone is sufficient. The pharmacy staff should reserve the use of gloves to situations in which the safeguard of pharmacy staff is required due to risk of infection, or to comply with infection prevention and control (IPAC) and National Association of Pharmacy Regulatory Authorities (NAPRA) standards and/or guidelines. Refraining from using latex or nitrile gloves when not medically necessary is an important aspect of environmental stewardship to be considered by healthcare professionals. Minimizing the use of gloves can help reduce environmental waste associated with disposable medical supplies, contributing to sustainability efforts in healthcare facilities. Approximately 500 boxes of gloves were found to emit 2 tonnes of CO2 emissions. Limiting the use of gloves is highly effective in promoting environmental sustainability. Recommendation #11.

Don’t dispose of adaptive equipment, mobility devices, orthoses, and prostheses that can be reused or recycled.

In rehabilitation medicine, the premature disposal of adaptive equipment such as orthoses, prostheses, and mobility devices (such as wheelchairs or walkers) is commonplace, often occurring before the end of their useful lifespans. Despite some efforts within the rehabilitation sector to promote reuse and recycling, there likely remains a significant communication gap between patients and healthcare providers regarding the importance of these practices. Beyond their environmental benefits, reuse offers benefits to patients by increasing access to vital equipment they may otherwise struggle to afford or obtain. By raising awareness and facilitating action towards extending the usefulness of adaptive devices or repurposing of components, stakeholders not only reduce waste but also ensure continued support for individuals through their rehab journeys, locally and/or globally. Recommendation #7.

Don’t necessarily conduct in-person visits for psychiatric care when a virtual visit is both clinically appropriate and acceptable to the patient. This is particularly relevant for visits which would otherwise involve lengthy or difficult travel by either the patient or the health care provider.

Driving is one of the activities with a high carbon footprint. Cars emit an average of 206 g of CO2 per kilometre. To put this in context a mature tree metabolizes about 20 kg of CO2 per year, the equivalent of driving less than 100 km. Travel to and from health facilities by patients, visitors and staff accounted for 10 per cent of the UK NHS emissions. Travel is a significant contributor to health care emissions.

In a cross-sectional study of more than 10 million patients and 63 million virtual care visits, virtual care was associated with avoidance of 3.2 billion km of patient travel, 545 to 658 million kg of carbon dioxide emissions, and $569 to $733 million (Canadian [US $465-$599 million]) in expenses for gasoline, parking, or public transit.

There is an increasing volume of literature which shows that mental health care delivered virtually can be as effective as in-person care. Recommendation #13.

Don’t prescribe protracted courses of radiotherapy when there is evidence to support equivalence of a hypofractionated or shorter fraction regimen. 

Hypofractionated or shortened radiation regimens have been documented to attain similar efficacy and safety as conventional and longer radiation courses for multiple tumor sites. By reducing the number of treatments, patient travel and machine time are reduced, thereby decreasing carbon emissions and energy demands of radiotherapy. Recommendation #12.

Canadian Association of Radiation Oncology

Don’t book multi-day patient visits for radiation treatments when these can be coordinated into a single trip.

A major source of the carbon footprint in the delivery of radiotherapy stems from the travels of the patients and staff to the radiation centres. As Canadian radiation facilities are centralized within larger towns and cities, public transits are commonly available. Active transportation is associated with many co-health benefits. Health care centres should ensure facilities exist to support active commuting (ex. showers, secure bike storage). Public transport when available should be incentivized, and in communities lacking this resource, health centres should advocate for this service. Recommendation #13.

Canadian Association of Radiation Oncology

Don’t do unnecessary imaging for cancer staging, treatment planning, and image verification in the context of clinical yield. Imaging is carbon intensive.

Medical imaging is estimated to account for 1% of global GHG emissions. For example, a single MRI abdomen is estimated to generate emissions equivalent to driving a motor vehicle almost 300km. The annual energy requirements and carbon emissions associated with commonly used investigations in increasing order are: ultrasound system (2500 kWh, 0.74 tCO2e), CT scanner (20 000 – 35 000 kWH, 5.9-10.4 tCO2e), PET-CT scanner (52 000 kWH, 15.4 tCO2e), and MRI scanner (80 000-170 000 kWh, 23.7-50.3 tCO2e). Data for onboard imaging and picture storage is currently limited but an active area of research. Recommendation #14.

Canadian Association of Radiation Oncology

Do not use single use disposable items when recyclable or reusable alternatives exist in clinics and brachytherapy departments.

Hospital and clinic waste is transported to landfills or incinerated resulting in significant GHG emissions. Choosing reusable supplies (ex. Gowns, drapes) or recyclable products (ex. Masks, sterilization wraps) over products that are incinerated can significantly reduce carbon emissions. Proper disposal of medical waste (ex. not contaminating recyclables with biohazards) is critical. Health care providers are encouraged to support clinical waste audits in their departments. Recommendation #15.

Canadian Association of Radiation Oncology

Don’t conduct in-person visits for oncology care if a virtual visit is feasible, safe, clinically appropriate (i.e. no physical exam required, not for delivery of bad news or major updates) and is preferred by the patient.

Several guidelines exist for the use of virtual care in oncology. These emphasize importance of calculated and appropriate triage, maximizing safety and equity. Transportation is currently the largest source of greenhouse gas (GHG) emissions. Cars emit an average of 206g of CO2 emissions per km. Virtual care can mitigate climate change by providing care from a distance and is also associated with substantial cost benefits and improved access. Various studies have shown that virtual visits are associated with a significant reduction in CO2 emissions as well as significant cost reductions to patients. Recommendation #16.

Joint Recommendation: Canadian Association of Medical Oncologists, Canadian Association of Radiation Oncology, Canadian Society of Surgical Oncology

Don’t dispose of non-contaminated wrapping materials in contaminated waste bins.

Disposal of non-contaminated waste leads to CO2 emissions due to the need for high-temperature incineration. The carbon footprint of disposal of biohazardous clinical waste via high temperature incineration is 1074 kg CO2e/ton compared to regular waste (172–249 kg CO2e/ton) and recycling (21–65 kg CO2e). Various studies have shown that non-contaminated waste generated in the operating room during a primary joint replacement is on average between 5.2 kg and 6.2 kg. Thus, implementing correct waste segregation practices of non-contaminated materials, will aid in reducing the overall impact of emissions on the environment. Recommendation #17.

Don’t include unnecessary or rarely used surgical instruments and supplies on surgical trays for routine otolaryngology procedures.

Waste in procedures from reusable surgical instruments and disposable surgical supplies can be reduced through tray optimization. Tray optimization aims to only include surgical instruments and supplies that are necessary and remove instruments and supplies that are rarely or never used. At one hospital, optimizing tonsillectomy/adenotonsillectomy trays was projected to decrease annual waste by 1.48 tons and save $830 in waste disposal costs annually (Penn et al.). In a 2023 UK study, which looked at five of the most common surgeries, the three highest carbon footprint contributing products for tonsillectomy included the single-use instrument table drape, single-use suction tubing, and reusable tonsillectomy set container (Rizan et al.) Most studies in the Otolaryngology-Head and Neck surgery literature on surgical instrument tray optimization have focussed on tray size reduction, improved OR efficiency metrics, reduced OR and turnover time, reduced tray processing and rebuilding times, and cost reduction/savings. Carbon footprint savings can be extrapolated from these results although it may not be explicitly stated in the present studies. Recommendation #10.

Don’t prescribe greenhouse gas-intensive metered-dose inhalers (MDIs) for asthma and/or COPD where an alternative inhaler with a lower carbon footprint (e.g. dry powder inhaler (DPI), soft-mist inhaler, or MDI with a low greenhouse gas potential propellant) containing medications with comparable efficacy is available, and where the patient has demonstrated adequate technique and patient preference has been considered.

Metered-dose inhalers (MDIs) contain HFC propellants, which contribute to global warming. When prescribing inhalers, providers should consider whether an objective diagnosis of asthma and/or COPD exists or needs to be confirmed, in keeping with existing CWC CTS recommendations (#1 and #5). Also, optimal choice of controller inhaler agents and non-pharmacologic strategies (e.g. education, trigger avoidance, action plans) should always be included in airway disease management, as they not only improve patient outcomes, but can also reduce rescue inhaler use.

Low carbon footprint inhalers may not be appropriate for some patients (i.e. preschool children, individuals with certain cognitive limitations, end-stage lung disease, muscle weakness or other physical limitations, and during respiratory emergencies). Other patients simply prefer MDIs. Ultimately, whether starting or substituting an inhaler, providers must consider medication efficacy, patient preference, adherence, technique, cost, and side-effect profile. A shared decision-making approach should be used, and the environmental benefits of alternatives to greenhouse gas-intensive MDIs should also inform this decision. Recommendation #8.

Don’t perform serological, imaging, or genetic tests without checking for and considering past available results.

In addition to increasing healthcare costs and blood draws from patients, redundant diagnostic testing for rheumatic disease adds carbon emissions through sample procurement, equipment, and processing. Beyond the tests themselves, patient transport to/from facilities and sample transport (including, for some tests, across institutions, provinces, or countries) adds to the carbon footprint. Ordering providers need to consider the reliability and validity of prior results, as well as the patients’ clinical evolution, when deciding whether repeat testing could be justified.

Because repeat testing may occur if test results performed elsewhere are not readily available, integrating electronic medical records across systems to facilitate rapid retrieval of external test results may curb redundant testing without contributing to providers’ administrative burden. Within a single health system, testing algorithms could prevent inadvertent repeat testing. Recommendation #10.

Don’t dispose of regular waste in a biohazardous waste container when performing joint aspirations or injections.

Joint aspirations and injections create biohazardous and non-biohazardous waste. Since biohazardous waste is incinerated before going to the landfill, it generates higher greenhouse gas emissions than other types of waste disposal. Avoid placing regular, non-biohazardous waste in biohazard/sharps containers to reduce unnecessary incineration and associated emissions. Recommendation #11.

Don’t use single-use vials of anesthetic agents such as xylocaine to prepare injections for patients.

Multi-dose vials (MDVs) that contain anesthetics like lidocaine or bupivacaine can be used safely when following manufacturer’s guidelines. Vials should be marked with first entry date, disinfected with a 70% alcohol swab and allowed to dry, only be penetrated by a new needle and syringe, kept in a secure area, and stored at room temperature. The vials should be discarded according to the manufacturer’s instructions (usually within 28 days) or within provincial guidelines whichever is shorter in duration. Recommendation #6.