Medical intelligence article: assessing the impact on global climate from general anesthetic gases

Carbon Footprint of Total Intravenous and Inhalation Anesthesia in the Transcatheter Aortic Valve Replacement Procedure

OBJECTIVES

To quantify and compare the emissions for deep sedation with total intravenous anesthesia (TIVA) and general anesthesia with inhaled agents during the transcatheter aortic valve replacement procedure.

DESIGN

A retrospective study.

SETTING

A tertiary hospital in Boston, Massachusetts.

PARTICIPANTS

The anesthesia records of 604 consecutive patients who underwent the transcatheter aortic valve replacement procedure between January 1, 2018, and March 31, 2022, were reviewed and analyzed.

INTERVENTIONS

Data were examined and compared in the following 2 groups: general anesthesia with inhaled agents and deep sedation with TIVA.

MEASUREMENTS AND MAIN RESULTS

The gases, drugs, airway management devices, and anesthesia machine electricity were collected and converted into carbon dioxide emissions (CO2e). The carbon emissions of intravenous medications were converted with the CO2e data for anesthetic pharmaceuticals from the Parvatker et al. study. For inhaled agents, inhaled anesthetics and oxygen/air flow rate were collected at 15-minute intervals and calculated using the anesthetic gases calculator provided by the Association of Anesthetists. The airway management devices were converted based on life-cycle assessments. The electricity consumed by the anesthesia machine during general anesthesia was estimated from the manufacturer's data (Dräger, GE) and local Energy Information Administration data. The data were analyzed in the chi-squared test or Wilcoxon rank-sum test. There were no significant differences in the patients' demographic characteristics, such as age, sex, weight, height, and body mass index. The patients who received general anesthesia with inhaled agents had statistically higher total CO2e per case than deep sedation with TIVA (16.188 v 1.518 kg CO2e; p < 0.001), primarily due to the inhaled agents and secondarily to airway management devices. For deep sedation with TIVA, the major contributors were intravenous medications (71.02%) and airway management devices (16.58%). A subgroup study of patients who received sevoflurane only showed the same trend with less variation.

CONCLUSIONS

The patients who received volatile anesthesia were found to have a higher CO2e per case. This difference remained after a subgroup analysis evaluating those patients only receiving sevoflurane and after accounting for the differences in the duration of anesthesia. Data from this study and others should be collectively considered as the healthcare profession aims to provide the best care possible for their patients while limiting the harm caused to the environment.

Estimating the Carbon Footprint of Healthcare in the Canton of Geneva and Reduction Scenarios for 2030 and 2040

Switzerland, a wealthy country, has a cutting-edge healthcare system, yet per capita, it emits over one ton of CO2, ranking among the world's most polluting healthcare systems. To estimate the carbon footprint of the healthcare system of Geneva's canton, we collected raw data on the activities of its stakeholders. Our analysis shows that when excluding medicines and medical devices, hospitals are the main greenhouse gas emitter by far, accounting for 48% of the healthcare system's emission, followed by nursing homes (20%), private practice (18%), medical analysis laboratories (7%), dispensing pharmacies (4%), the homecare institution (3%), and the ambulance services (<1%). The most prominent emission items globally are medicines and medical devices by far, accounting for 59%, followed by building operation (19%), transport (11%), and catering (4%), among others. To actively reduce Geneva's healthcare carbon emissions, we propose direct and indirect measures, either with an immediate impact or implementing systemic changes concerning medicine prescription, building heating and cooling, low-carbon means of transport, less meaty diets, and health prevention. This study, the first of its kind in Switzerland, deciphers where most of the greenhouse gas emissions arise and proposes action levers to pave the way for ambitious emission reduction policies. We also invite health authorities to engage pharmaceutical and medical suppliers in addressing their own responsibilities, notably through the adaptation of procurement processes and requirements.

Transforming into a Learning Health System: A Quality Improvement Initiative

Background

The Institute of Medicine introduced the Learning Healthcare System concept in 2006. The system emphasizes quality, safety, and value to improve patient outcomes. The Bellevue Clinic and Surgical Center is an ambulatory surgical center that embraces continuous quality improvement to provide exceptional patient-centered care to the pediatric surgical population.

Methods

We used statistical process control charts to study the hospital's electronic health record data. Over the past 7 years, we have focused on the following areas: efficiency (surgical block time use), effectiveness (providing adequate analgesia after transitioning to an opioid-sparing protocol), efficacy (creating a pediatric enhanced recovery program), equity (evaluating for racial disparities in surgical readmission rates), and finally, environmental safety (tracking and reducing our facility's greenhouse gas emissions from inhaled anesthetics).

Results

We have seen improvement in urology surgery efficiency, resulting in a 37% increase in monthly surgical volume, continued adaptation to our opioid-sparing protocol to further reduce postanesthesia care unit opioid administration for tonsillectomy and adenoidectomy cases, successful implementation of an enhanced recovery program, continued work to ensure equitable healthcare for our patients, and more than 85% reduction in our facility's greenhouse gas emissions from inhaled anesthetics.

Conclusions

The Bellevue Clinic and Surgical Center facility is a living example of a learning health system, which has evolved over the years through continued patient-centered QI work. Our areas of emphasis, including efficiency, effectiveness, efficacy, equity, and environmental safety, will continue to impact the community we serve positively.

Caregiver involvement in an approach favoring sustainable development in the operating theater

The climate emergency alarm is resounding. Tasked with caregiving, healthcare facilities are nonetheless responsible for apparently innumerable greenhouse gas emissions. Predominantly atmospheric pollution causes 9 million deaths a year throughout the world. While legislative measures have been taken to favor change in climate-related business practices, the effects of their implementation are far from visible. On a parallel track, caregivers have been coming together and calling into question their practices, the objective being to institute concrete actions leading to reduction of healthcare-related carbon footprint. Not all of these actions have the same ecological impact or ease of implementation. To demonstrate their effectiveness and set the stage for readjustments, the existing initiatives require qualitative assessment and quantitative appraisal. While they demand personal motivation and professional investment, these efforts have a triple impact, at once ecological, economic and related to quality of life. Multidisciplinary teams come together in the pursuit of a common project epitomizing our missions as caregivers; is not that the essence of our presence in hospital?

Electricity consumption of anesthesia workstations and potential emission savings by avoiding standby

BACKGROUND

Anesthesiology has a relevant carbon footprint, mainly due to volatile anesthetics (scope 1 emissions). Additionally, energy used in the operating theater (scope 2 emissions) contributes to anesthesia-related greenhouse gas (GHG) emissions.

OBJECTIVES

Optimizing the electricity use of medical devices might reduce both GHG emissions and costs might hold potential to reduce anaesthesia-related GHG-emissions and costs. We analyzed the electricity consumption of six different anesthesia workstations, calculated their GHG emissions and electricity costs and investigated the potential to reduce emissions and cost by using the devices in a more efficient way.

METHODS

Power consumption (active power in watt , W) was measured with the devices off, in standby mode, or fully on with the measuring instrument SecuLife ST. Devices studied were: Dräger Primus, Löwenstein Medical LeonPlus, Getinge Flow C, Getinge Flow E, GE Carestation 750 and GE Aisys. Calculations of GHG emissions were made with different emission factors, ranging from very low (0.09 kg CO2-equivalent/kWh) to very high (0.660 kg CO2-equivalent/kWh). Calculations of electricity cost were made assuming a price of 0.25 € per kWh.

RESULTS

Power consumption during operation varied from 58 W (GE CareStation 750) to 136 W (Dräger Primus). In standby, the devices consumed between 88% and 93% of the electricity needed during use. The annual electricity consumption to run 96 devices in a large clinical department ranges between 45 and 105 Megawatt-hours (MWh) when the devices are left in standby during off hours. If 80% of the devices are switched off during off hours, between 20 and 46 MWh can be saved per year in a single institution. At the average emission factor of our hospital, this electricity saving corresponds to a reduction of GHG emissions between 8.5 and 19.8 tons CO2-equivalent. At the assumed prices, a cost reduction between 5000 € and 11,600 € could be achieved by this intervention.

CONCLUSION

The power consumption varies considerably between the different types of anesthesia workstations. All devices exhibit a high electricity consumption in standby mode. Avoiding standby mode during off hours can save energy and thus GHG emissions and cost. The reductions in GHG emissions and electricity cost that can be achieved with this intervention in a large anesthesiology department are modest. Compared with GHG emissions generated by volatile anesthetics, particularly desflurane, optimization of electricity consumption of anesthesia workstations holds a much smaller potential to reduce the carbon footprint of anesthesia; however, as switching off anesthesia workstations overnight is relatively effortless, this behavioral change should be encouraged from both an ecological and economical point of view.

A randomised controlled trial comparing quality of recovery between desflurane and isoflurane inhalation anaesthesia in patients undergoing ophthalmological surgery at a tertiary hospital in South Africa (DIQoR trial)

Background

The patient's experience of their postoperative recovery is an important perioperative outcome, with the 15-item quality of recovery scale (QoR-15) recommended as a standardised outcomes measure. Desflurane has a faster emergence from anaesthesia compared with other volatile anaesthetics, but it is uncertain whether this translates to better subjective quality of recovery. The hypothesis for this study is that patients receiving desflurane for maintenance of anaesthesia would have better postoperative quality of recovery than patients receiving isoflurane.

Methods

Male and female adult patients undergoing ophthalmological surgery under general anaesthesia were randomly allocated to receive desflurane or isoflurane for maintenance of anaesthesia. The primary outcome was to compare postoperative QoR-15 scores. Secondary outcomes included comparing preoperative QoR-15 scores, volatile agent consumption, and time spent in the recovery room.

Results

Data from 164 patients were analysed (80 desflurane, 84 isoflurane). Median (Q1, Q3) postoperative QoR-15 scores were not significantly different (desflurane: 145 [141, 148], isoflurane: 144 [139, 147], 95% confidence interval 0-3, P=0.176, minimal clinically important difference=8). Median (Q1, Q3) volatile agent consumption was 15.4 (12.5, 19.3) ml hr-1 in the desflurane group, and 7.4 (5.9, 9.7) ml hr-1 in the isoflurane group. Median (Q1, Q3) time spent in the recovery room was significantly shorter in the desflurane group (desflurane: 18 [13, 23]; isoflurane: 25 [19, 32], 95% confidence interval -10 to 5, P<0.001).

Conclusions

This study found no difference in quality of recovery between patients who received desflurane or isoflurane for maintenance of general anaesthesia during ophthalmological surgery. A shorter time in the recovery room was not associated with improved QoR-15 scores.

Clinical trial registration

NCT04188314.

Inhalational volatile anaesthetic agents: the atmospheric scientists' viewpoint

All sectors of society must reduce their carbon footprint to mitigate climate change, and the healthcare community is no exception. This narrative review focuses on the environmental concerns associated with the emissions of volatile anaesthetic agents, some of which are potent greenhouse gases. This review provides an understanding of the global warming potential metric, as well as the concepts of atmospheric lifetime and radiative efficiency. The state of knowledge of the environmental impact and possible climate forcing of emitted volatile anaesthetic agents are reviewed. Additionally, the review discusses how climate metrics can guide mitigation strategies to reduce emissions and suggests present and future options for mitigating the climate impact.

Easy-to-implement educational interventions to bring climate-smart actions to daily anesthesiologic practice: a cross-sectional before and after study

BACKGROUND

Anesthesia contributes significantly to a hospital's carbon footprint. Climate-smart actions have the potential to reduce greenhouse gas emissions. Prerequisites for sustainable behavior of providers are knowledge and awareness. We aimed to assess the change in anesthesiologists' climate-friendly behavior before and after educational interventions in three areas that every anesthesiologist can address in their daily clinical routine: 1) energy use; 2) recycling opportunities; 3) consumption of volatile anesthetics.

METHODS

We performed a cross-sectional before-and-after single center sub-study within the multicenter "Provider Education and Evaluation Project" at the Department of Anesthesiology, RWTH Aachen University hospital from May3 2021 to May 1 2022. Educational interventions consisted of stickers, posters and a presentation on climate-smart actions in anesthesiologists' work routine between the first and the second assessment. For each cross-sectional assessment, all central 28 ORs were observed for one week. During the before-and-after comparison we analyzed: 1) energy wasted in unoccupied ORs because of running computers and turned-on lights at 9 p.m.; 2) feasibility of recycling preoperative anesthesia plastic packaging by determining the difference between calculated weight of unseparated preoperative plastic waste in the first assessment and the weight of actual separated waste in the second assessment; 3) fresh gas flow in balanced anesthesia cases in steady state at 9 a.m., and purchased hypnotics converted to bottles/1000 general anesthesia cases in 2018-2022.

RESULTS

We observed a reduction of wasted energy by 44% in unoccupied ORs. Usage of low fresh gas flow settings increased from 55% to 75%. The average of purchased desflurane in 2018-2020 decreased by 72% in 2022. We calculated 10.33 kg of preoperative plastic waste per week but were unable to implement waste separation for infrastructural and logistical reasons.

CONCLUSIONS

We found that environment-friendly working behaviors increased after the implementation of educational interventions. The causality between the interventions and the observed improvements remains to be proven.

Addressing Climate Health: A Practical Guide to Quantifying and Reducing Health Care-Associated Emissions

OBJECTIVE

The objective was to quantify annual greenhouse gas emissions from a surgical specialty hospital and identify high-yield areas to reduce emissions associated with patient care.

STUDY DESIGN

Pre-post study, greenhouse gas inventory.

SETTING

Specialty hospital.

METHODS

A scope 1 and scope 2 greenhouse gas inventory of the Massachusetts Eye and Ear main campus for calendar years (CY) 2020, 2021, and 2022 was performed by assessing emissions attributable to on-site sources (scope 1) and purchased electricity and steam (scope 2). The associated carbon dioxide equivalent was then calculated using known global warming potentials and emission factors.

RESULTS

The major contributors to scope 1 and scope 2 emissions at our institution for CY 2020 to 2022 were waste anesthetic gases and purchased steam. These results were reviewed with hospital leadership and a plan was developed to reduce these emissions. Emission monitoring is ongoing to assess the efficacy of these interventions.

CONCLUSION

Measuring scope 1 and scope 2 emissions at the facility level allows health care facilities to develop institution-specific interventions and compare data across health care organizations. Surgeons can lead on health care system sustainability by collaborating with clinical and nonclinical staff to measure emissions, developing targeted emissions-reduction interventions, and tracking progress with yearly assessments.

Estimation of the carbon footprint of arthroscopic rotator cuff repairs in France

AIM

The main objective of this study was to estimate the carbon impact of arthroscopic rotator cuff repairs in France. The secondary objective was to assess the effectiveness of the following measures in reducing the carbon footprint associated with this technique: outpatient treatment, arthroscopic water filtration, surgery under locoregional anesthesia.

HYPOTHESIS

The hypothesis was that the carbon footprint could be significantly improved with the implementation of these three procedures.

METHODS

A continuous series of 26 patients who underwent surgery for a rotator cuff tear involving only one tendon between November 2020 and April 2021 were included. The evaluation protocol consisted of three parts: 1/ use of volatile anesthetic agents; 2/ electrical consumption linked to the procedure; 3/ emissions related to patient and staff travel, delivery of implants and waste management. Another series of 26 patients operated between November 2018 and April 2019 who had none of these three factors were matched.

RESULTS

The carbon impact of arthroscopic repair of the rotator cuff was estimated at 334.61±18.82kgCO2eq. The implementation of the three methods for improvement made it possible to significantly reduce emissions by 40.9±1.71kgCO2eq (12.2%) (p<0.001).

CONCLUSION

Performing surgery under locoregional anesthesia, on an outpatient basis with water purification, reduces the carbon impact of arthroscopic rotator cuff repair by more than 12%.

LEVEL OF EVIDENCE

III, retrospective case control.

Paving the way to environment-friendly greener anesthesia

Health-care settings have an important responsibility toward environmental health and safety. The operating room is a major source of environmental pollution within a hospital. Inhalational agents and nitrous oxide are the commonly used gases during general anesthesia for surgeries, especially in the developing world. These greenhouse gases contribute adversely to the environmental health both inside the operating room and in the outside atmosphere. Impact of these anesthetic agents depends on the total consumption, characteristics of individual agents, and gas flows, with higher levels increasing the environmental adverse effects. The inimical impact of nitrous oxide is higher due to its longer atmospheric half-life and potential for destruction of the ozone layer. Anesthesiologist of today has a choice in the selection of anesthetic agents. Prudent decisions will help in mitigating environmental pollution and contributing positively to a greener planet. Therefore, a shift from inhalational to intravenous-based technique will reduce the carbon footprint of anesthetic agents and their impact on global climate. Propofol forms the mainstay of intravenous anesthesia technique and is a proven drug for anesthetic induction and maintenance. Anesthesiologists should appreciate growing concerns about the role of inhalational anesthetics on the environment and join the cause of environmental responsibility. In this narrative review, we revisit the pharmacological and pharmacokinetic considerations, clinical uses, and discuss the merits of propofol-based intravenous anesthesia over inhalational anesthesia in terms of environmental effects. Increased awareness about the environmental impact and adoption of newer, versatile, and user-friendly modalities of intravenous anesthesia administration will pave the way for greener anesthesia practice.

Estimating the carbon emissions from a resource-limited surgical suite in Papua New Guinea: The climate change potential

Introduction

The upscale of surgical service delivery in low to middle income countries will increase health sector greenhouse gas emissions globally. Understanding surgical greenhouse gas emissions from surgical suite activities can direct decarbonization strategies and achieve local, and global climate change objectives.

Material and methods

A prospective surgical suite carbon foot print study was conducted at the Alotau Provincial Hospital from the 28th March 2022 to the 28th of May 2022.

Results

The total carbon emission for the surgical suite in APH over the study period was 2,665.8 kgCO2e. The average carbon emission per surgical case within the boundary of the surgical suite was 8.4 kgCO2e. Scope one emissions (anaesthetic gases) accounted for 44.7% (1171.3 kgCO2e) of all carbon emissions.

Conclusion

If no action is taken, carbon emissions in the western pacific region will continue to increase from surgical suites. Therefore, proactive efforts to reduce greenhouse gas emissions must be prioritized.

Nitrous Oxide Use in Australian Health Care: Strategies to Reduce the Climate Impact

Nitrous oxide is a useful inhaled analgesic. Due to its high global warming potential and ozone-depleting properties, the nitrous oxide emissions related to health care are being increasingly scrutinized. In this narrative review, we will discuss the clinical uses of nitrous oxide relevant to anesthetists, in addition to its contribution as a greenhouse gas. Using available data from Australia, we will explore potential strategies for reducing the impact of those emissions, which are likely to be applicable in other countries. These include destruction of captured nitrous oxide, minimizing nitrous oxide waste and reducing clinical use. Anesthesia clinicians are well placed to raise awareness with colleagues and consumers regarding the environmental impact of nitrous oxide and to promote cleaner alternatives. Reducing use is likely to be the most promising reduction strategy without large-scale changes to infrastructure and subsequent delay in action.

Guidelines for reducing the environmental impact of general anaesthesia

OBJECTIVE

To provide guidelines for reducing the environmental impact of general anaesthesia.

DESIGN

A committee of ten experts from SFAR and SF2H and SFPC learned societies was set up. A policy of declaration of competing interests was applied and observed throughout the guideline-writing process. Likewise, it did not benefit from any funding from a company marketing a health product (drug or medical device). The committee followed the GRADE® method (Grading of Recommendations Assessment, Development and Evaluation) to assess the quality of the evidence on which the recommendations were based.

METHODS

We aimed to formulate recommendations according to the GRADE® methodology for three different fields: anaesthesia vapours and gases; intravenous drugs; medical devices and the working environment. Each question was formulated according to the PICO format (Population, Intervention, Comparator, Outcome). The literature review and recommendations were formulated according to the GRADE® methodology.

RESULTS

The experts' work on the synthesis and application of the GRADE® method led to the formulation of 17 recommendations. Since the GRADE® method could not be entirely applied to all of the questions, some of the recommendations were formulated as expert opinions.

CONCLUSION

Based on strong agreement between experts, we produced 17 recommendations designed to guide reducing the environmental impact of general anaesthesia.

Assessing the potential climate impact of anaesthetic gases

There is increasing concern within the health-care community about the role care delivery plays in environmental degradation, sparking research into how to reduce pollution from clinical practice. Inhaled anaesthetics is a particular research area of interest for two reasons. First, several gases are potent greenhouse gases, and waste gas is mostly emitted directly to the environment. Second, there are options to reduce gas waste and substitute medications and procedures with fewer embodied emissions while delivering high-quality care. Performance improvements are contingent on a proper understanding of the emission estimates and climate metrics used to ensure consistent application in guiding mitigation strategies and accounting at various scales. We review the current literature on the environmental impact and the estimation of the potential climate forcing of common inhaled anaesthetic drugs: desflurane, sevoflurane, isoflurane, methoxyflurane, and nitrous oxide.

Project SPRUCE: Saving Our Planet by Reducing Carbon Emissions, a Pediatric Anesthesia Sustainability Quality Improvement Initiative

BACKGROUND

Children are particularly vulnerable to adverse health outcomes related to climate change. Inhalational anesthetics are potent greenhouse gasses (GHGs) and contribute significantly to health care-generated emissions. Desflurane and nitrous oxide have very high global warming potentials. Eliminating their use, as well as lowering fresh gas flows (FGFs), will lead to reduced emissions.

METHODS

Using published calculations for converting volatile anesthetic concentrations to carbon dioxide equivalents (CO 2 e), we derived the average kilograms (kg) CO 2 e/min for every anesthetic administered in the operating rooms at our pediatric hospital and ambulatory surgical center between October 2017 and October 2022. We leveraged real-world data captured from our electronic medical record systems and used AdaptX to extract and present those data as statistical process control (SPC) charts. We implemented recommended strategies aimed at reducing emissions from inhalational anesthetics, including removing desflurane vaporizers, unplugging nitrous oxide hoses, decreasing the default anesthesia machine FGF, clinical decision support tools, and educational initiatives. Our primary outcome measure was average kg CO 2 e/min.

RESULTS

A combination of educational initiatives, practice constraints, protocol changes, and access to real-world data were associated with an 87% reduction in measured GHG emissions from inhaled anesthesia agents used in the operating rooms over a 5-year period. Shorter cases (<30 minutes duration) had 3 times higher average CO 2 e, likely due to higher FGF and nitrous oxide use associated with inhalational inductions, and higher proportion of mask-only anesthetics. Removing desflurane vaporizers corresponded with a >50% reduction of CO 2 e. A subsequent decrease in anesthesia machine default FGF was associated with a similarly robust emissions reduction. Another significant decrease in emissions was noted with educational efforts, clinical decision support alerts, and feedback from real-time data.

CONCLUSIONS

Providing environmentally responsible anesthesia in a pediatric setting is a challenging but achievable goal, and it is imperative to help mitigate the impact of climate change. Large systems changes, such as eliminating desflurane, limiting access to nitrous oxide, and changing default anesthesia machine FGF rates, were associated with rapid and lasting emissions reduction. Measuring and reporting GHG emissions from volatile anesthetics allows practitioners to explore and implement methods of decreasing the environmental impact of their individual anesthesia delivery practices.

Environmental and Economic Impact of Using a Higher Efficiency Ventilator and Vaporizer During Surgery Under General Anesthesia: A Randomized Controlled Prospective Cohort

Background Compared to traditional breathing circuits, low-volume anesthesia machines utilize a lower-volume breathing circuit paired with needle injection vaporizers that supply volatile agents into the circuit mainly during inspiration. We aimed to assess whether or not low-volume anesthesia machines, such as the Maquet Flow-i C20 anesthesia workstation (MQ), deliver volatile anesthetics more efficiently than traditional anesthesia machines, such as the GE Aisys CS² anesthesia machine (GE), and, secondarily, whether this was in a meaningful economic or environmentally conscious way. Methodology Participants enrolled in the study (Institutional Review Board Identifier: 2014-1248) met the following inclusion criteria: 18-65 years old, scheduled for surgery requiring general anesthesia at the University of California Irvine Health, and expected to receive sevoflurane for the duration of the procedure. Exclusion criteria included age <18 years old, a history of chronic obstructive pulmonary disorder, cardiovascular disease, sevoflurane sensitivity, body mass index >30 kg/m², American Society of Anesthesiologists >2, pregnancy, or surgery scheduled <120 minutes. We calculated the total amount of sevoflurane delivered and consumption rates during induction and maintenance periods and compared the groups using one-sided parametric testing (Student's t-test). There was no suspicion that the low-volume circuit could use more sevoflurane and that the outcome did not answer our research question. One-sided testing allowed for more power to be more certain of smaller differences in our results. Results In total, 103 subjects (MQ: n = 52, GE: n = 51) were analyzed. Seven subjects were lost to attrition of different types. Overall, the MQ group consumed significantly less sevoflurane (95.5 ± 49.3 g) compared to the GE group (118.3 ± 62.4 g) (p = 0.043), corresponding to an approximately 20% efficiency improvement in overall agent delivery. When accounting for the fresh gas flow setting, agent concentration, and length of induction, the MQ delivered the volatile agent at a significantly lower rate compared to the GE (7.4 ± 3.2 L/minute vs. 9.1 ± 4.1 L/minute; p = 0.017). Based on these results, we estimate that the MQ can save an estimated average of $239,440 over the expected 10-year machine lifespan. This 20% decrease in CO₂ equivalent emissions corresponds to 201 metric tons less greenhouse gas emissions over a decade compared to the GE, which is equivalent to 491,760 miles driven by an average passenger vehicle or 219,881 pounds of coal burned. Conclusions Overall, our results from this study suggest that the MQ delivers statistically significantly less (~20%) volatile agent during routine elective surgery using a standardized anesthetic protocol and inclusion/exclusion criteria designed to minimize any patient or provider heterogeneity effects on the results. The results demonstrate an opportunity for economic and environmental benefits.

Anaesthesia and environment: impact of a green anaesthesia on economics

The excessive growth of the health sector has created an industry that, while promoting health, is now itself responsible for a significant part of global environmental pollution. The health crisis caused by climate change urges us to transform healthcare into a sustainable industry. This review aims to raise awareness about this issue and to provide practical and evidence-based recommendations for anaesthesiologists.

The green anaesthesia dilemma: to which extent is it important to preserve as many drugs available as possible

PURPOSE OF REVIEW

This article aims to summarize the current literature describing the availability of different anaesthetic drugs, and to discuss the advantages and limitations of a self-imposed restriction on the scarcely existing anaesthetic drugs.

RECENT FINDINGS

Earth temperature has risen 1.2°C since the beginning of industrial age, and it is expected to exceed a 1.5°C increase by 2050. The Intergovernmental Panel on Climate Change depicts five different scenarios depending on how these increased temperatures will be controlled in the future. The European Commission has formulated a proposal to regulate fluorinated greenhouse gases (F-gases), among which desflurane, isoflurane and sevoflurane belong to, due to their high global warming potential. This proposal shall ban, or severely restrict, the use of desflurane starting January 2026. It is not clear what might happen with other F-gas anaesthetics in the future. Due to climate change, a higher number of health crisis are expected to happen, which might impair the exiting supply chains, as it has happened in previous years with propofol scarcity.

SUMMARY

There are just a handful number of available anaesthetics that provide for a safe hypnosis. Major stakeholders should be consulted prior making such severe decisions that affect patient safety.

A call for immediate climate action in anesthesiology: routine use of minimal or metabolic fresh gas flow reduces our ecological footprint

PURPOSE

Climate change is a global threat, and inhalational anesthetics contribute to global warming by altering the photophysical properties of the atmosphere. On a global perspective, there is a fundamental need to reduce perioperative morbidity and mortality and to provide safe anesthesia. Thus, inhalational anesthetics will remain a significant source of emissions in the foreseeable future. It is, therefore, necessary to develop and implement strategies to minimize the consumption of inhalational anesthetics to reduce the ecological footprint of inhalational anesthesia.

SOURCE

We have integrated recent findings concerning climate change, characteristics of established inhalational anesthetics, complex simulative calculations, and clinical expertise to propose a practical and safe strategy to practice ecologically responsible anesthesia using inhalational anesthetics.

PRINCIPAL FINDINGS

Comparing the global warming potential of inhalational anesthetics, desflurane is about 20 times more potent than sevoflurane and five times more potent than isoflurane. Balanced anesthesia using low or minimal fresh gas flow (≤ 1 L·min-1) during the wash-in period and metabolic fresh gas flow (0.35 L·min-1) during steady-state maintenance reduces CO2 emissions and costs by approximately 50%. Total intravenous anesthesia and locoregional anesthesia represent further options for lowering greenhouse gas emissions.

CONCLUSION

Responsible anesthetic management choices should prioritize patient safety and consider all available options. If inhalational anesthesia is chosen, the use of minimal or metabolic fresh gas flow reduces the consumption of inhalational anesthetics significantly. Nitrous oxide should be avoided entirely as it contributes to depletion of the ozone layer, and desflurane should only be used in justified exceptional cases.

Climate toxicity: An increasingly relevant clinical issue in Cancer Care

In recent years the terms time and financial toxicities have entered the vocabulary of cancer care. We would like to introduce another toxicity: climate toxicity. Climate toxicity is a double-edge sword in cancer care. Increasing cancer risk by exposure to carcinogens, and consequently increasing treatment requirements leads to ever growing damage to our environment. This article assesses the impact of climate change on patients, the climate toxicity caused by both healthcare workers and healthcare facilities, and suggests actions that may be taken mitigate them.

Production and possible reduction of greenhouse gases produced during GI endoscopy activity: a systematic review of available literature

BACKGROUND AND AIMS

Greenhouse gases (GHGs) that trap heat in the atmosphere are composed of carbon dioxide (CO2), methane, nitrous oxide and fluorinated gases (synthetic hydrofluorocarbons, perfluorocarbons and nitrogen trifluoride). In the USA, the health sector accounts for 8.5% of total GHG emissions. The primary objective of this systematic review was to critically analyse the carbon emissions data from GI endoscopic activity.

DESIGN

The GI endoscopy carbon cycle was evaluated at preprocedural, intraprocedural and postprocedural levels. We performed a systematic literature search of articles published on these issues until 30 June 2022 and discussed these available data on endoscopy unit GHG carbon cycle, barriers to reduce GHG emissions and potential solutions. The inclusion criteria were any full-text articles (observational, clinical trials, brief communications, case series and editorials) reporting waste generation from GI endoscopy. Abstracts, news articles and conference proceedings were excluded.

RESULTS

Our search yielded 393 records in PubMed, 1708 in Embase and 24 in Google Scholar. After application of inclusion and exclusion factors, we focused on 9 fulllength articles in detail, only 3 of them were cross-sectional studies (all from the USA), the others reviews or position statements. Therefore, the quality of the studies could not be assessed due to heterogeneity in definitions and amount of emissions.

CONCLUSIONS

Recognition of carbon emissions generated by GI endoscopy activity is critical. Although multiple limitations exists for quantification of these emission, there is an urgent need for collecting proper data as well as examining novel methods for reduction of these emissions for a sustainable endoscopic practices in the future.

The intersection of pediatric surgery, climate change, and equity

Climate change is occurring at an unprecedented rate. Recent years have seen heatwaves, wildfires, floods, droughts, and re-emerging infectious diseases fueled by global warming. Global warming has also increased the frequency and severity of surgical disease, particularly for children, who bear an estimated 88% of the global burden of disease attributable to climate change. Health care delivery itself weighs heavily on the environment, accounting for nearly 5% of global greenhouse gas emissions. Within the health care sector, surgery and anesthesia are particularly carbon intensive. The surgical community must prioritize the intersection of climate change and pediatric surgery in order to address pediatric surgical disease on a global scale, while reducing the climate impact of surgical care delivery. This review defines the current state of climate change and its effects on pediatric surgical disease, discusses climate justice, and outlines actions to reduce the climate impact of surgical services. LEVEL OF EVIDENCE: Level V.

Association Between Anesthesia Provider Education and Carbon Footprint Related to the Use of Inhaled Halogenated Anesthetics

BACKGROUND

Inhaled halogenated anesthetics are responsible for half of operating room total greenhouse gas emissions. Sustainable anesthesia groups were set up in 4 Lyon, France, university hospitals (Hospices Civils de Lyon) in January 2018 and have supported a specific information campaign about the carbon footprint related to the use of inhaled halogenated anesthetics in June 2019. We aimed to assess whether implementing such information campaigns was associated with a decrease in the carbon footprint related to inhaled halogenated anesthetics.

METHODS

This retrospective cohort study was conducted from January 1, 2015, to February 29, 2020, in 4 hospitals of the Hospices Civils de Lyon in France. Information meetings on sustainable anesthesia practices were organized by sustainable anesthesia groups that were set up in January 2018. In addition, a specific information campaign about the carbon footprint related to inhaled halogenated anesthetics was conducted in June 2019; it was followed by a questionnaire to be completed online. The monthly purchase of sevoflurane, desflurane, and propofol was recorded, and the estimated monthly carbon footprint from desflurane- and sevoflurane-related perioperative emissions was calculated. The interrupted time-series data from January 2015 to February 2020 were analyzed by segmented regression, considering both interventions (setting up of the sustainable anesthesia groups and specific information campaign) in the analysis and adjusting for 2 confounding factors (seasonality of the data and number of general anesthesia uses).

RESULTS

Among the 641 anesthesia providers from the study hospitals, 121 (19%) attended the information meetings about the carbon footprint of inhaled halogenated anesthetics, and 180 (28%) completed the questionnaire. The anesthetic activity from all 641 providers was considered in the analysis. After the sustainable anesthesia groups were set up, the carbon footprint of sevoflurane and desflurane started decreasing: the slope significantly changed ( P < .01) and became significantly negative, from -0.27 (95% confidence interval [CI], -1.08 to 0.54) tons.month -1 to -14.16 (95% CI, -16.67 to -11.65) tons.month -1 . After the specific information campaign, the carbon footprint kept decreasing, with a slope of -7.58 (95% CI, -13.74 to -1.41) tons.month -1 ( P = .02), which was not significantly different from the previous period ( P = .07).

CONCLUSIONS

The setup of the sustainable anesthesia groups was associated with a dramatic reduction in the carbon footprint related to halogenated anesthetics. These results should encourage health care institutions to undertake information campaigns toward anesthesia providers so that they also take into account the environmental impact in the choice of anesthetic drugs, in addition to the benefits for the patient and economic concerns.

Prospective validation of gas man simulations of sevoflurane in O2/air over a wide fresh gas flow range

The use of inhaled anesthetics has come under increased scrutiny because of their environmental effects. This has led to a shift where sevoflurane in O₂/air has become the predominant gas mixture to maintain anesthesia. To further reduce environmental impact, lower fresh gas flows (FGF) should be used. An accurate model of sevoflurane consumption allows us to assess and quantify the impact of the effects of lowering FGFs. This study therefore tested the accuracy of the Gas Man® model by determining its ability to predict end-expired sevoflurane concentrations (F_ETsevo) in patients using a protocol spanning a wide range of FGF and vaporizer settings. After IRB approval, 28 ASA I-II patients undergoing a gynecologic or urologic procedure under general endotracheal anesthesia were enrolled. Anesthesia was maintained with sevoflurane in O₂/air, delivered via a Zeus or FLOW-i workstation (14 patients each). Every fifteen min, FGF was changed to randomly selected values ranging from 0.2 to 6 L/min while the sevoflurane vaporizer setting was left at the discretion of the anesthesiologist. The F_ETsevo was collected every min for 1 h. For each patient, a Gas Man® simulation was run using patient weight and the same FGF, vaporizer and minute ventilation settings used during the procedure. For cardiac output, the Gas Man default setting was used (= Brody formula). Gas Man®'s performance was assessed by comparing measured with Gas Man® predicted F_ETsevo using linear regression and Varvel's criteria [median performance error (MDPE), median absolute performance error (MDAPE), and divergence]. Additional analysis included separating performance for the wash-in (0-15 min) and maintenance phase (15-60 min). For the FLOW-i, MDPE, MDAPE and divergence were 1% [- 6, 8], 7% [3, 15] and - 0.96%/h [- 1.14, - 0.88], respectively. During the first 15 min, MDPE and MDAPE were 18% [1, 51] and 21% [8, 51], respectively, and during the last 45 min 0% [- 7, 5] and 6% [2, 10], respectively. For the Zeus, MDPE, MDAPE and divergence were 0% [- 5, 8], 6% [3, 12] and - 0.57%/h [- 0.85, - 0.16], respectively. During the first 15 min, MDPE and MDAPE were 7% [- 6, 28] and 13% [6, 32], respectively, and during the last 45 min - 1% [- 5, 5] and 5% [2, 9], respectively. In conclusion, Gas Man® predicts F_ETsevo in O₂/air in adults over a wide range of FGF and vaporizer settings using different workstations with both MDPE and MDAPE < 10% during the first hour of anesthesia, with better relative performance for simulating maintenance than wash-in. In the authors' opinion, this degree of performance suffices for Gas Man® to be used to quantify the environmental impact of FGF reduction in real life practice of the wash-in and maintenance period combined.

[Environmentally friendly absorption of anesthetic gases : First experiences with a commercial anesthetic gas capture system]

Anesthetic gases are potent greenhouse gases, which are currently released into the atmosphere where they remain for many years. Strategies to reduce the carbon footprint in anesthesiology without compromising patient safety are urgently needed. Since 2020 several departments of anesthesiology have installed anesthetic gas capture systems with which anesthetic gases can be collected. This article aims to describe the anesthetic gas capture system CONTRAfluran™ and to give an overview of the first experiences in four departments of anesthesiology working with the new device in the daily clinical routine. The CONTRAfluran™ system presents a new concept in the surgical setting that has the potential to reduce the carbon footprint in anesthesiology; however, in order to accurately estimate CO₂ equivalent savings, more information concerning the reprocessing and data on the pharmacokinetics of anesthetic gases are needed. Application of the CONTRAfluran™ system in daily clinical routine is feasible when anesthesiologists are aware of specific issues. In order to minimize the carbon footprint, it remains essential to implement the specific recommendations in the position paper of the German Society of Anaesthesiology and Intensive Care medicine (DGAI) and the Professional Association of German Anaesthesiologists (BDA) on ecological sustainability in anesthesiology and intensive care medicine and to support further research.

The science behind banning desflurane: A narrative review

Potent inhaled anaesthetics are halogenated hydrocarbons with a large global warming effect. The use of fluorinated hydrocarbons (most are not anaesthetics) are being restricted but volatile anaesthetics have been exempted from legislation, until now: the EU has formulated a proposal to ban or at least severely restrict the use of desflurane starting January 2026. This narrative review addresses the implications of a politics-driven decision - without prior consultation with major stakeholders, such as the European Society of Anaesthesiology and Intensive Care (ESAIC) - on daily anaesthesia practice and reviews the potential scientific arguments that would support stopping the routine use of desflurane in anaesthetic practice. Of note, banning or severely restricting the use of one anaesthetic agent should not distract the user from sensible interventions like reducing fresh gas flows and developing technology to capture and recycle or destroy the wasted potent inhaled anaesthetics that we will continue to use. We call to join efforts to minimise our professional environmental footprint.

Reducing the environmental footprint of gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) Position Statement

Climate change and the destruction of ecosystems by human activities are among the greatest challenges of the 21st century and require urgent action. Health care activities significantly contribute to the emission of greenhouse gases and waste production, with gastrointestinal (GI) endoscopy being one of the largest contributors. This Position Statement aims to raise awareness of the ecological footprint of GI endoscopy and provides guidance to reduce its environmental impact. The European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) outline suggestions and recommendations for health care providers, patients, governments, and industry. MAIN STATEMENTS 1: GI endoscopy is a resource-intensive activity with a significant yet poorly assessed environmental impact. 2: ESGE-ESGENA recommend adopting immediate actions to reduce the environmental impact of GI endoscopy. 3: ESGE-ESGENA recommend adherence to guidelines and implementation of audit strategies on the appropriateness of GI endoscopy to avoid the environmental impact of unnecessary procedures. 4: ESGE-ESGENA recommend the embedding of reduce, reuse, and recycle programs in the GI endoscopy unit. 5: ESGE-ESGENA suggest that there is an urgent need to reassess and reduce the environmental and economic impact of single-use GI endoscopic devices. 6: ESGE-ESGENA suggest against routine use of single-use GI endoscopes. However, their use could be considered in highly selected patients on a case-by-case basis. 7: ESGE-ESGENA recommend inclusion of sustainability in the training curricula of GI endoscopy and as a quality domain. 8: ESGE-ESGENA recommend conducting high quality research to quantify and minimize the environmental impact of GI endoscopy. 9: ESGE-ESGENA recommend that GI endoscopy companies assess, disclose, and audit the environmental impact of their value chain. 10:  ESGE-ESGENA recommend that GI endoscopy should become a net-zero greenhouse gas emissions practice by 2050.

Carbon footprint of inhalational and total intravenous anaesthesia for paediatric anaesthesia: a modelling study

BACKGROUND

Tackling the climate emergency is now a key target for the healthcare sector. Avoiding inhalational anaesthesia is often cited as an important element of reducing anaesthesia-related emissions. However, evidence supporting this is based on adult practice. The aim of this study was to identify the difference in carbon footprint of inhalational and i.v. anaesthesia when used in children.

METHODS

We used mathematical simulation models to compare general anaesthetic techniques in children weighing 5-50 kg for TIVA, i.v. induction then inhalational maintenance, inhalational induction then i.v. maintenance, and inhalational induction and maintenance. We simulated inhalational induction with sevoflurane alone, and co-induction with sevoflurane and nitrous oxide, and both remifentanil-propofol and propofol-only i.v. anaesthesia. For each technique, we drew on previously published life-cycle data to calculate carbon dioxide equivalents for anaesthetic durations up to 480 min.

RESULTS

TIVA with propofol and remifentanil had a smaller carbon footprint over a typical anaesthetic duration of 60 min (1.26 kg carbon dioxide equivalents [CO₂e] for a 20 kg child) than i.v. induction followed by inhalational maintenance (2.58 kg CO₂e) or inhalational induction and maintenance (2.98 kg CO₂e). Inhalational induction followed by i.v. maintenance only had a lower carbon footprint than inhalational induction and maintenance when used in longer procedures (>77 min for children 5-20 kg; >105 min for children 30-50 kg).

CONCLUSIONS

In a simulation study, i.v. anaesthesia had climate benefits in paediatric anaesthesia. However, when used after inhalational induction, benefits were only achieved in longer procedures. These findings provide evidence-based guidance for reducing the environmental impact of paediatric anaesthesia, but these will require confirmation using real-world data.

Greenhouse gas reduction in anaesthesia practice: a departmental environmental strategy

Sustainability interventions were implemented at the Royal Brisbane and Women’s Hospital (RBWH) following identification of inhaled anaesthetic gases as a target for reducing medical carbon emissions. This quality improvement study assessed and evaluated the impact of sustainability interventions on the environmental and financial cost of inhaled anaesthetic gas use in order to guide future initiatives and research in reducing carbon emissions from healthcare practice.

Ethical exemption was granted from the RBWH Research Ethics Committee (EX/2021/QRBW/76078). Usage (bottles) and expenditure for desflurane and sevoflurane from January 2016 to December 2021 were obtained. Global warming potential and carbon dioxide equivalent (CO₂e) were used to report environmental impact of volatile agents. Methods to estimate this were performed in Excel based on Campbell and Pierce methodology. An Environmental Protection Agency greenhouse gas equivalency calculator was used to convert CO₂e to equivalent petrol carbon emissions and kilometres travelled by a typical passenger vehicle.

The total number of bottles of sevoflurane and desflurane purchased between January 2016 and December 2021 decreased by 34.76% from 1991 to 1299. The number of desflurane bottles purchased decreased by 95.63% from 800 to 35 bottles. The number of sevoflurane bottles purchased increased by 6.13% from 1191 bottles to 1264 bottles. This was achieved by implementing quality improvement interventions such as staff education of desflurane-sparing practices, distribution of posters and progressive removal of desflurane from operating theatres. Total carbon emission from volatile anaesthetics equalled 2326 tonnes CO₂e. Combined desflurane and sevoflurane emissions decreased by 87.88%. In 2016, desflurane made up 92.39% of the annual CO₂e, which steadily decreased to 33.36% in 2021. Combined sevoflurane and desflurane usage costs decreased by 58.33%.

Substantial reductions in carbon emissions from volatile anaesthetics demonstrate the significant degree to which environmentally sustainable practices have been implemented. Applying desflurane-sparing practice can heavily limit anaesthetic drug expenditure and contribution to environmental waste. This is important given the global health sector’s challenge to optimise patient outcomes in the face of global climate change crisis.

The Effects of Switching from Sevoflurane to Short-Term Desflurane prior to the End of General Anesthesia on Patient Emergence and Recovery: A Randomized Controlled Trial

While sevoflurane and desflurane have been regarded as inhalation agents providing rapid induction and emergence, previous studies demonstrated the superiority of desflurane-anesthesia compared to sevoflurane-anesthesia in the postoperative recovery in obese and geriatric patients. We investigated whether a short-term switch of sevoflurane to desflurane at the end of sevoflurane-anesthesia enhances patient postoperative recovery profile in non-obese patients. We randomly divide patients undergoing elective surgery (n = 60) into two groups: sevoflurane-anesthesia group (Group-S, n = 30) and sevoflurane-desflurane group (Group-SD, n = 30). In Group-S, patients received only sevoflurane-anesthesia until the end of surgery (for >2 hours). In Group-SD, sevoflurane was stopped and switched to desflurane-anesthesia before the completion of sevoflurane-anesthesia (for approximately 30 minutes). We assessed the intergroup differences in the times to get eye-opening, extubation, and a bispectral index of 80 (BIS-80). Group-SD showed significantly shorter times to get eye-opening (438 ± 101 vs. 295 ± 45 s; mean difference, 143 s; 95% confidence interval [CI], 101–183; p < 0.001), extubation (476 ± 108 vs. 312 ± 42 s; mean difference, 164 s; 95% CI, 116–220; p < 0.001), and BIS-80 (378 ± 124 vs. 265 ± 49 minutes; mean difference, 113 s; 95% CI, 58–168 p < 0.001) compared to Group-S. There was no between-group difference in postoperative nausea, vomiting, and hypoxia incidences. Our results suggested that the short-term (approximately 30 minutes) switch of sevoflurane to desflurane at the end of sevoflurane-anesthesia can facilitate the speed of postoperative patient recovery.

Assessing the Environmental Carbon Footprint of Spinal versus General Anesthesia in Single-Level Transforaminal Lumbar Interbody Fusions

BACKGROUND

The U.S. health care sector produces approximately 10% of national greenhouse gas emissions, paradoxically harming human health. Neurosurgery is a resource-intensive specialty that likely contributes significantly, yet literature assessing this impact is absent. We investigate the difference in carbon emissions between spinal versus general anesthesia in lumbar spine surgery.

METHODS

A total of 100 patients underwent a single-level transforaminal lumbar interbody fusion (TLIF) from a single surgeon; 50 received spinal anesthesia and 50 received general anesthesia. Data were extracted from patient records. Amounts of anesthetics were calculated from intraoperative records and converted to carbon dioxide equivalents (CO₂e).

RESULTS

The median CO₂e for general anesthesia was 4725 g versus 70 g for spinal anesthesia (P = 7.07e-18). The mean CO₂e for general anesthesia was 22,707 g versus 63 g for spinal anesthesia. Desflurane use led to outsized carbon emissions. Carbon footprint comparisons are made with familiar units such as miles driven by a car, and are provided for a single TLIF, 50 TLIFs (single surgeon's cases in a year), and 488,000 TLIFs (annual spinal fusions in the United States).

CONCLUSION

This is one of the first known comparative carbon footprint studies performed in neurosurgical literature. We highlight the dramatic carbon footprint reduction associated with using spinal anesthesia and reflect a single neurosurgeon's change in practice from using only general anesthesia to incorporating the use of spinal anesthesia. Within general anesthesia patients, desflurane use was particularly harmful to the environment. We hope that our study will pave the way toward future research aimed at uncovering and reducing neurosurgery's environmental impact.

Action guidance for addressing pollution from inhalational anaesthetics

Climate change is a real and accelerating existential danger. Urgent action is required to halt its progression, and everyone can contribute. Pollution mitigation represents an important opportunity for much needed leadership from the health community, addressing a threat that will directly and seriously impact the health and well‐being of current and future generations. Inhalational anaesthetics are a significant contributor to healthcare‐related greenhouse gas emissions and minimising their climate impact represents a meaningful and achievable intervention. A challenge exists in translating well‐established knowledge about inhalational anaesthetic pollution into practical action. CODA is a medical education and health promotion charity that aims to deliver climate action‐oriented recommendations, supported by useful resources and success stories. The CODA‐hosted platform is designed to maximise engagement of the global healthcare community and draws upon diverse experiences to develop global solutions and accelerate action. The action guidance for addressing pollution from inhalational anaesthetics is the subject of this article. These are practical, evidence‐based actions that can be undertaken to reduce the impact of pollution from inhalational anaesthetics, without compromising patient care and include: removal of desflurane from drug formularies; decommissioning central nitrous oxide piping; avoidance of nitrous oxide use; minimising fresh gas flows during anaesthesia; and prioritising total intravenous anaesthesia and regional anaesthesia when clinically safe to do so. Guidance on how to educate, implement, measure and review progress on these mitigation actions is provided, along with means to share successes and contribute to the essential, global transition towards environmentally sustainable anaesthesia.

Reduction of greenhouse gases emission through the use of tiletamine and zolazepam

Isoflurane is an anaesthetic gas widely used in both human and veterinary medicine. All currently used volatile anaesthetics are ozone-depleting halogenated compounds. The use of total intravenous anaesthesia (TIVA) allows to induce the effect of general anaesthesia by administering drugs only intravenously without the use of anaesthetic gases. This allows you to create a protocol that is safe not only for the patient, but also for doctors and the environment. However, so far, no anaesthetic protocol based on induction of anaesthesia with tiletamine-zolazepam without the need to maintain anaesthesia with anaesthetic gas has been developed. Our study showed that the use of this combination of drugs for induction does not require the use of additional isoflurane to maintain anaesthesia. Thanks to Dixon's up-and-down method we proved that with the induction of anaesthesia with tiletamine-zolazepam at a dose of 5 mg/kg the use of isoflurane is not needed to maintain anaesthesia in minimally invasive surgical procedures. Until now, this dose has been recommended by the producer for more diagnostic than surgical procedures or for induction of general anaesthesia. The maintenance was required with anaesthetic gas or administration of another dose of the tiletamine-zolazepam. The results obtained in this study will allow for a significant reduction in the consumption of isoflurane, a gas co-responsible for the deepening of the greenhouse effect, having a negative impact on patients and surgeons. These results are certainly the first step to achieving a well-balanced and safe TIVA-based anaesthetic protocol using tiletamine-zolazepam, the obvious goal of which will be to maximize both the safety of the patient, people involved in surgical procedures, and the environment itself. Being aware of the problem of the greenhouse effect, we are committed to reducing the consumption of anaesthetic gases by replacing them with infusion agents.

Dataset for carbon footprints of transforaminal lumbar interbody fusions performed under spinal or general anesthesia

The datasets presented here quantify and compare the relative carbon footprints emitted by general versus spinal anesthesia in patients undergoing single-level transforaminal lumbar interbody fusions (TLIFs). Data were retrospectively collected from electronic medical records of 100 consecutive patients who underwent a single-level TLIF from a single neurosurgeon at a U.S. academic center. 50 patients were under general anesthesia, and another 50 patients were under spinal anesthesia. Clinic and operative notes were used to extract demographic and surgical information, whereas anesthesia records were used to extract anesthetic information. Using the anesthetic information, carbon dioxide equivalents (CO2e) were calculated for each type of anesthetic and summed together to compute the total carbon footprint for each patient. Our article entitled "Assessing the environmental carbon footprint of spinal versus general anesthesia in single-level transforaminal lumbar interbody fusions" is based on this data [1]. Raw datasets of the primary data collection as well as cleaned and analyzed datasets are presented. These datasets highlight the first known environmental impact calculation from medical records of a spine procedure, serving as a model for other interested investigators to explore and emulate. This data brief may help to pave the way towards future environmental research and practice changes within neurosurgical and orthopedic literature, an issue critical to the sustainability of our modern society.