The Glasgow declaration on sustainability in Anaesthesiology and Intensive Care

Efficiency of CONTRAfluran™ in reducing sevoflurane pollution from maintenance anaesthesia in minimal flow end-tidal control mode for laparoscopic surgery: Efficiency of CONTRAfluran™

BACKGROUND

Recommendations exist that aim to mitigate the substantial ecological impact of anaesthesia. One option is to use anaesthetic gas capturing technology at anaesthesia workstation exhausts to harvest and recycle volatile agents. However, the efficiency of such technology is mainly unverified in vivo.

METHODS

The efficiency of CONTRAfluran™ in capturing sevoflurane from an anaesthesia workstation exhaust (when set to minimal flow and end-tidal control mode) was evaluated in 70 adult patients scheduled for general or bariatric laparoscopic surgery. The weight of the sevoflurane vaporiser and CONTRAfluran canister was measured before and after each case, to calculate total sevoflurane consumption and retention. Retention was measured after the minimal flow maintenance phase and after the high flow washout phase. The total retention efficiency was the fraction of all consumed sevoflurane captured by the CONTRAfluran canister. The primary objective was to examine the retention efficiency of CONTRAfluran in a clinical surgical setting, where all feasible strategies to minimise sevoflurane consumption and optimise the efficacy of CONTRAfluran were utilised. The secondary objective was to analyse the correlation between mass transfer and the duration of the case.

RESULTS

Mean (SD) volume of sevoflurane captured using CONTRAfluran was 4.82 (1.41) ml, representing 45% (95%CI 42-48%) of all sevoflurane administered. The highest amount of retention was found during the washout phase. Retention efficiency did not correlate with the duration of the case.

CONCLUSIONS

Over half of the sevoflurane administered was not captured by the CONTRAfluran canister when minimal flow techniques were used, likely due to residual accumulation of sevoflurane in the patient after tracheal extubation or, to a lesser extent, due to ventilation system leakage. However, as every prevented emission is commendable, CONTRAfluran may be a potentially valuable tool for reducing the environmental footprint of sevoflurane-based anaesthesia.

Environmental impact of anesthetic drugs

PURPOSE OF REVIEW

The environmental impact of anesthesia far exceeds that of other medical specialties due to our use of inhaled anesthetic agents (which are potent greenhouse gases) and many intravenous medications.

RECENT FINDINGS

Calls for reducing the carbon footprint of anesthesia are ubiquitous in the anesthesia societies of developed nations and are appearing in proposed changes for hospital accreditation and funding in the United States. The body of research on atmospheric, land and water impacts of anesthetic pharmaceuticals is growing and generally reinforces existing recommendations to reduce the greenhouse gas emissions of anesthesia care.

SUMMARY

The environmental impact of anesthesia care should factor into our clinical decisions. The onus is on clinicians to safely care for our patients in ways that contribute the least harm to the environment. Intravenous anesthesia and regional techniques have less environmental impact than the use of inhaled agents; efforts to reduce and properly dispose of pharmaceutical waste are central to reducing environmental burden; desflurane should not be used; nitrous oxide should be avoided except where clinically necessary; central nitrous pipelines should be abandoned; low fresh gas flows should be utilized whenever inhaled agents are used.

Haemodynamic monitoring during noncardiac surgery: past, present, and future

During surgery, various haemodynamic variables are monitored and optimised to maintain organ perfusion pressure and oxygen delivery - and to eventually improve outcomes. Important haemodynamic variables that provide an understanding of most pathophysiologic haemodynamic conditions during surgery include heart rate, arterial pressure, central venous pressure, pulse pressure variation/stroke volume variation, stroke volume, and cardiac output. A basic physiologic and pathophysiologic understanding of these haemodynamic variables and the corresponding monitoring methods is essential. We therefore revisit the pathophysiologic rationale for intraoperative monitoring of haemodynamic variables, describe the history, current use, and future technological developments of monitoring methods, and finally briefly summarise the evidence that haemodynamic management can improve patient-centred outcomes.

Teleconsultation for Preoperative Anesthesia Evaluation: Identifying Environmental Potentials by Life Cycle Assessment

Introduction: Teleconsultations for preoperative evaluation in anesthesiology proved to be feasible during the COVID-19 pandemic. However, widespread implementation of teleconsultations has not yet occurred. Besides time savings and economic benefits, teleconsultations in anesthesia may have the potential to reduce CO2 emissions. Methods: We conducted a life cycle assessment based on prospective surveys to assess the potential environmental benefits of preoperative anesthesia teleconsultations in comparison to the status-quo in-person consultations. Within 1 month, all patients presenting at the preoperative anesthesia clinic at RWTH Aachen University Hospital were asked about the distance traveled and mode of transportation to the hospital. The main outcome measure was the potential environmental benefit resulting from the implementation of teleconsultations. Results: In total, 821 out of 981 patients presenting at the anesthesia clinic participated in the survey. Most patients visited on an outpatient basis (62.9%) and traveled by car (81.7%). The median travel distance was 25 km [interquartile range 12-40]. If patients who came to the hospital solely for the anesthesia appointment had scheduled virtual appointments, the emissions of 3.03-ton CO2 equivalents (CO2-eq) could be avoided in the first month after implementation. The environmental impact associated with the production of teleconsultation equipment is outweighed by the reduction in patient travel. If all outpatient appointments were performed virtually, these savings would triple. Within 10 years, more than 1,300 tons CO2-eq could be avoided. Conclusion: Teleconsultations can mitigate the environmental impact of in-person anesthesia consultations. Further research is essential to leverage teleconsultations for preoperative evaluation also across other medical specialties.

Comparison of automated and manual control methods in minimal flow anesthesia

PURPOSE

New-generation anesthesia machines administer inhalation anesthetics and automatically control the fresh gas flow (FGF) rate. This study compared the administration of minimal flow anesthesia (MFA) using the automatically controlled anesthesia (ACA) module of the Mindray A9 (Shenzhen, China) anesthesia machine versus manual control by an anesthesiologist.

METHODS

We randomly divided 76 patients undergoing gynecological surgery into an ACA group (Group ACA) and a manually controlled anesthesia group (Group MCA). In Group MCA, induction was performed with a mixture of 40-60% O2 and air with a 4 L/min FGF until the minimum alveolar concentration (MAC) reached 1. Next, MFA was initiated with 0.5 L/min FGF. The target fraction of inspired oxygen (FiO2) value was 35-40%. In Group ACA, the MAC was defined as 1, and the FiO2 was adjusted to 35%. Depth of anesthesia, anesthetic agent (AA) consumption, time to achieve target end-tidal AA concentration, awakening times, and number of ventilator adjustments were analyzed.

RESULTS

The two groups showed no statistically significant differences in depth of anesthesia or AA consumption (Group ACA: 19.1 ± 4.9 ml; Group MCA: 17.2 ± 4.5; p-value = 0.076). The ACA mode achieved the MAC target of 1 significantly faster (Group ACA: 218 ± 51 s; Group MCA: 314 ± 169 s). The number of vaporizer adjustments was 15 in the ACA group and 217 in the MCA group.

CONCLUSION

The ACA mode was more advantageous than the MCA mode, reaching target AA concentrations faster and requiring fewer adjustments to achieve a constant depth of anesthesia.

Healthcare in the era of climate change and the need for environmental sustainability

ABSTRACT

Climate change is an existential threat to humanity. While the healthcare sector must manage the health-related consequences of climate change, it is a significant contributor to greenhouse gas emissions, responsible for up to 4.6% of global emission, aggravating global warming. Within the hospital environment, the three largest contributors to greenhouse gas emissions are the operating theatre, intensive care unit and gastrointestinal endoscopy. Knowledge of the health-related burden of climate change and the potential transformative health benefits of climate action is important to all health professionals, as they play crucial roles in effecting change. This article summarises the available literature on the impact of healthcare on climate change and efforts in mitigation, focusing on the intrinsic differences and similarities across the operating theatre complex, intensive care unit and gastrointestinal endoscopy unit. It also discusses strategies to reduce carbon footprint.

European Society of Anaesthesiology and Intensive Care consensus document on sustainability: 4 scopes to achieve a more sustainable practice

Climate change is a defining issue for our generation. The carbon footprint of clinical practice accounts for 4.7% of European greenhouse gas emissions, with the European Union ranking as the third largest contributor to the global healthcare industry's carbon footprint, after the United States and China. Recognising the importance of urgent action, the European Society of Anaesthesiology and Intensive Care (ESAIC) adopted the Glasgow Declaration on Environmental Sustainability in June 2023. Building on this initiative, the ESAIC Sustainability Committee now presents a consensus document in perioperative sustainability. Acknowledging wider dimensions of sustainability, beyond the environmental one, the document recognizes healthcare professionals as cornerstones for sustainable care, and puts forward recommendations in four main areas: direct emissions, energy, supply chain and waste management, and psychological and self-care of healthcare professionals. Given the urgent need to cut global carbon emissions, and the scarcity of evidence-based literature on perioperative sustainability, our methodology is based on expert opinion recommendations. A total of 90 recommendations were drafted by 13 sustainability experts in anaesthesia in March 2023, then validated by 36 experts from 24 different countries in a two-step Delphi validation process in May and June 2023. To accommodate different possibilities for action in high- versus middle-income countries, an 80% agreement threshold was set to ease implementation of the recommendations Europe-wide. All recommendations surpassed the 80% agreement threshold in the first Delphi round, and 88 recommendations achieved an agreement >90% in the second round. Recommendations include the use of very low fresh gas flow, choice of anaesthetic drug, energy and water preserving measures, "5R" policies including choice of plastics and their disposal, and recommendations to keep a healthy work environment or on the importance of fatigue in clinical practice. Executive summaries of recommendations in areas 1, 2 and 3 are available as cognitive aids that can be made available for quick reference in the operating room.

A Survey on Environmental Sustainability Among Anesthesiologists: An Opportunity for Changing Behaviors

Introduction  Environmental sustainability (ES) is a current issue related to natural resource scarcity, pollution and climate change. Although operating rooms (ORs) comprise a small proportion of the entire hospital infrastructure, they significantly impact the environment. Anesthesiologists are ideally positioned to assume leadership, mitigating this negative impact regarding OR waste in the environment. We created a Green Team, comprising multidisciplinary professionals from different areas of a tertiary Portuguese medical center, and conducted a survey that was sent to all the institution's anesthesiologists to assess the current state of ES. Results  From the sample of 133 participants, 101 responses were obtained. Concerning knowledge and training on ES, a significant portion of the respondents (66.7%) seem to attribute "great importance" to the subject. As to the greatest barrier to waste separation in the OR, several respondents highlighted the issues of "inadequate information/education/training" (62.6%) and "lack of support from hospital/OR in-chief/administration" (26.3%). Finally, among seven methods to raise awareness of ES, "training during residency" was the top choice for these professionals, with 52.5% of the votes. Discussion  Most anesthesiologists who responded to the survey recognize the utmost importance of ES and have perceived the environmental impact of their anesthetic practices in the OR. Overall, this tendency is consistent with other international studies. Moreover, most of those surveyed separate waste at home and want to extend this practice -in a more structured approach- to their workplace, with an effective separation of anesthetic and general waste in the OR. Conclusion Professionals perceive barriers to performing green practices, whether the lack of environmental education and awareness, the absence of recycling containers or waste separation bags, or the lack of protocols and guidelines implementing these circuits. With the publication of this work, we aim to encourage other institutions to implement ES projects in their hospitals and ORs.

Environmental and economic impact of sustainable anaesthesia interventions: a single-centre retrospective observational study

BACKGROUND

Anaesthesia contributes substantially to the environmental impact of healthcare. To reduce the ecological footprint of anaesthesia, a set of sustainability interventions was implemented in the University Hospital Zurich, Switzerland. This study evaluates the environmental and economic implications of these interventions.

METHODS

This was a single-centre retrospective observational study. We analysed the environmental impact and financial implications of changes in sevoflurane, desflurane, propofol, and plastic consumption over 2 yr (April 2021 to March 2023). The study included pre-implementation, implementation, and post-implementation phases.

RESULTS

After implementation of sustainability measures, desflurane use was eliminated, there was a decrease in the consumption of sevoflurane from a median (inter-quartile range) of 25 (14-39) ml per case to 11 (6-22) ml per case (P<0.0001). Propofol consumption increased from 250 (150-721) mg per case to 743 (370-1284) mg per case (P<0.0001). Use of plastics changed: in the first quarter analysed, two or more infusion syringes were used in 62% of cases, compared with 74% of cases in the last quarter (P<0.0001). Two or more infusion lines were used in 58% of cases in the first quarter analysed, compared with 68% of cases in the last quarter (P<0.0001). This resulted in an 81% reduction in overall environmental impact from 3 (0-7) to 1 (0-3) CO2 equivalents in kg per case (P<0.0001). The costs during the final study phase were 11% lower compared with those in the initial phase: from 25 (13-41) to 21 (14-31) CHF (Swiss francs) per case (P<0.0001).

CONCLUSIONS

Implementing sustainable anaesthesia interventions can significantly reduce the environmental impact and cost of anaesthesia.