Healthcare sustainability in cardiothoracic surgery

Introduction

The increasing reality of climate change poses an existential threat to human health.^1-3 Extreme weather events such as heatwaves, wildfires, droughts and floods that are directly and indirectly lethal are occurring with growing frequency globally.³ Despite political commitments like the Paris Agreement and United Nations Framework Convention on Climate Change, energy related carbon emissions are still escalating, reaching a record high in 2022.³ On the current trajectory, the global temperature rise seems imminent within the decade heralding even more natural disasters.^{1, 3} Healthcare as a sector is responsible for up to 5% of global greenhouse gas (GHG) emissions and we cannot continue ignoring our substantial environmental footprint.^4-6 In the burgeoning field of climate and health, we find on one hand that climate-sensitive health risks are increasing, and on the other, healthcare continues to contribute significantly to climate change.⁷ As a speciality, cardiothoracic surgery has a vested interest in this as our patients are among the most vulnerable to climate change.⁸ We hope to spotlight this pressing issue, take stock of the sustainability of our current practices and encourage fellow specialists to advocate for sustainable practice change.

The status quo

When one considers the amount of waste generated in our daily practice, especially with single use disposables, one can begin to appreciate the extent of our emissions. Through the course of the pandemic, the widespread adoption of disposable personal protective equipment, SARS-COV-2 vaccines and testing kits has further increased our waste produced.⁹ Models predict upwards of 8 million tonnes of pandemic-associated plastic waste being generated globally with the bulk of it being hospital waste.¹⁰ Still, this barely scratches the surface of the magnitude of healthcare's carbon footprint: waste production only accounts for 5% of the carbon footprint in health systems and recycling efforts address only a fraction of this waste.¹¹ Bulk of the emissions arise from supply chains and delivery of care.¹¹ Our job to save lives on the frontlines has thus far given us a free pass in global climate action efforts. Only in recent years have the concepts of sustainable healthcare and healthcare decarbonization come to the fore.¹² Without healthcare joining the cause, achieving ‘drawdown’ (i.e., the point at which GHGs plateau and decline to reverse global warming) would simply be a pipe dream.¹³

Our colleagues across the drapes have made great strides in leading the healthcare decarbonization movement,^{5, 14} going so far as to have the Royal College of Anaesthetists integrate environmental sustainability as part of their curriculum.¹⁵ Anaesthetists are the sole prescribers of anaesthetic gases which have a disproportionate global warming potential compared to carbon dioxide and are able to directly (i.e., Scope 1) decrease some of their GHG emissions by changing their clinical practice.¹⁶ As surgeons, our emissions incurred are mainly indirect (i.e., Scope 2 and 3) via use of electricity, water and further upstream embodied in our surgical instruments. These may appear to be less actionable than Scope 1 emissions but are actually within our control. For example, specialties like ophthalmology,^{17, 18} obstetrics and gynaecology,^{19, 20} plastic surgery²¹ and general surgery^{22, 23} have started quantifying the carbon footprint of their procedures so as to identify solutions for carbon hotspots.^{24, 25} Similar to clinical practice, the best intervention is contingent on arriving at the correct diagnosis. As a resource intensive specialty that prides itself in innovation and cares for patients directly affected by pollution,²⁶ we have but one eco-audit of conventional heart surgery procedures by Grinberg et al.²⁷ In Grinberg's life cycle assessments of 28 cardiac surgeries, he calculated a mean emission of 124.3 kg carbon dioxide equivalent (CO₂e) for each cardiac surgery, the equivalent of a 1080 km plane ride for a single passenger, of which 89% of these emissions came from disposable medical products. This revelation shows that much more can be done to drive our specialty towards sustainable practices.

It would be remiss to say that cardiothoracic as a whole has not attempted to address the broad issue of sustainability. Most previous studies reference the United Nations 2015 Sustainable Development Goals framework and focused on the third tenet of ‘Good health and Well-being’, emphasizing the need for availing cardiothoracic capabilities to countries with limited access.^28-30 What these studies potentially neglect is that good environmental stewardship can pre-emptively negate the need for provision of specialty access as a downstream consequence.^{7, 8} Air pollution has been proven to be associated with cardiovascular disease^{31, 32} and PM_2.5 exposure even labelled as a modifiable factor by the American Heart Association.³³ The causal relationship air pollution has with lung cancer is conclusively becoming more definite.^{34, 35} Hence, there is an ethical imperative to focus on environmental sustainability to better care for our patients. By preventing them from incurring these diseases in the first place and improving the general population's health, we mitigate the consequences that include grappling with the complex logistics of travelling to a remote part of the world to initiate a subspecialty service. As physicians who swore to ‘do no harm’, we can do more to avert our patients' suffering by doing our part for the environment.

Triple bottom line

How then do we begin this herculean task? A good parameter to operate on would be by addressing the ‘Triple Bottom Line’ as described by Mortimer et al.³⁶ In the article, Mortimer redefines value in healthcare (i.e., $\text{Value}=\frac{\text{Quality}}{\text{Cost}}$) by tweaking the commonly used denominator of financial costs only to include both environmental impact (i.e., carbon footprint) and social demands (i.e., resources like time of healthcare professionals, carers and patients). She expands the concept of cost beyond just the monetary realm to account for the ecological and social payoffs that quality is balanced against. (i.e., $\text{Value}=\frac{\text{Quality}}{\text{Cost}+\text{Carbon}+\text{Social}}$) This seeks to imbue a more holistic perspective of value driven healthcare that considers more than just the economic bottom line. Using these guiding principles, we can effect change in both our group and personal practices within and outside the confines of the operating theatre whilst maintaining patient safety and satisfaction.

In the operating theatre

Cardiothoracic surgery by nature is high end surgery due to its complexity. Our procedures consume more resources be it time, manpower, energy or equipment. Our dominant position in the operating theatre,³ a well-documented high carbon footprint area,^{37, 38} allows us to spearhead changes that can be practical and impactful. A simple gesture of judiciously catheterizing only patients that require it, readily meets the triple bottom line and can be implemented immediately.³⁹ Choosing to use reusable equipment over single use disposables produce significant carbon savings and can be applied to drapes, gowns and instruments.⁴⁰ A general reduction in usage of instruments not only decreases plastics use, water and energy required for sterilization, it also lightens the cognitive demands on assisting staff and creates a more efficient surgery. In essence, the pursuit of surgical mastery and environmental sustainability are aligned.

This journey will force us to confront traditional practices that may not be rooted in best evidence. For example, many surgeons still routinely insufflate the cardiac surgical field with carbon dioxide for cerebral protection despite a meta-analysis by Benedetto et al. disproving this.⁴¹ Volatile anaesthetics such as Sevoflurane and Desflurane are potent and environmentally harmful GHGs. Outcomes of their use in cardiac surgery have been shown to be comparable to the greener alternative of total intravenous anaesthetics such as Propofol.^{4, 8, 42, 43} Yet anaesthetists justify continued use citing evidence from older publications.^{44, 45} Desflurane, which has 2540 times the environmental impact of carbon dioxide, is still routinely used in some thoracic centres despite studies demonstrating no difference in pulmonary outcomes and minimal benefits in emergence time.^{46, 47} As evidence based surgeons, we should embrace best practices that improve outcomes for our patients and the environment.

As surgeon innovators constantly pushing the boundaries, there also exists a dissonance between the pursuit of sustainability and technological advancement. Modern techniques such as robotic and video assisted thoracoscopic surgery have shown to entail a higher carbon footprint than conventional open surgery, contributed mainly by the procurement of sophisticated instruments required.¹⁹ We must ensure that the post-operative trade off in reduction of pain, length of stay and morbidity makes up for the higher carbon costs incurred intra-operatively.^{48, 49} Minimally invasive surgery should consistently deliver shorter inpatient stays, reduced perioperative consumption such as blood transfusion and medications. Furthermore, improved long term prognosis and benefits that may prevent recurrent admissions and procedures can offset the one-time carbon costs incurred. There is potential here for life cycle assessment research to account and justify the impact of new versus current practices. If these advances are found to grate against the triple bottom line we should be careful in adopting them blindly. On the flip side, caution must be taken against a race to the bottom. Advocating for sustainability must not be used as an excuse to revert to traditional practices that compromise modern standards of patient care. Progress should not be curtailed by the green agenda for the sake of but instead embed accountability for its impact on climate.

Outside the operating theatre

Beyond the confines of the operating theatre, we can transform our practice to be more sustainable as well. As the saying goes ‘the greenest building is the one that you don't build’.⁵⁰ In the surgical context this means ensuring that every procedure or investigation we subject our patients to is truly indicated.⁵¹ Complex cardiothoracic patients are often subject to a battery of perioperative evaluations that may not impact clinical decision making. We should be more deliberate and prudent in prescribing treatments.⁴⁹ Pathways like enhanced recovery after surgery (ERAS) can help standardize processes and make current practices leaner and more efficient. It is encouraging that ERAS is gaining increasing traction within our specialty.^{52, 53} Given that there is embodied carbon in everything that we do especially that of an additional inpatient stay,⁵⁴ reducing length of stay not only improves service quality, it saves costs and carbon as well.^{55, 56} Apart from the inpatient admission, outpatient consultations can also be transitioned to telemedicine consults for significant carbon savings mainly derived from travel reduction.⁵⁷

On an institutional level, better resource optimization of operating theatres, clinic spaces, instruments and manpower are required. More can be done to share resources across surgeons, care teams and health systems. Those of us privileged to be placed in positions of authority in health systems can help effect these changes on a wider scale. Contextual nuances exist across individual practices, hence surgical leads will need to actively examine their processes and implement practical interventions that are within their own sphere of influence.

Whether in public or private institutions, the green agenda is fast gaining traction with patients, healthcare professionals, governments and shareholders.⁵⁸ Administrators should start reviewing their hospitals' carbon footprint and initiate work groups to pare down emissions. Up to 10% of healthcare's emissions is scope 2 from electricity and water usage.¹¹ Hospitals need to revisit their infrastructure, pivot to renewable energy sources and adopt current green building best practices such as the Leadership in Energy and Environmental Design rating system.⁵⁹ These interventions will require multidisciplinary collaborations with architects and engineers and can be timed to coincide with major renovation or refurbishment works to future proof the premises.

Beyond the hospital

Beyond the scope of the hospital, more research, innovation and education should be directed towards improving the environmental sustainability of our techniques and tools. Short of delving into environmental research ourselves, we can advocate for sustainable advancements in technology. As end-users we have a significant voice, our demands on suppliers drive their innovation agenda.⁶⁰ We should begin requesting for environmental accountability in pharmaceutical driven research and development. We can base procurement decisions off such matrices whilst being vigilant of the risks of greenwashing.⁶¹ It is not uncommon to encounter profit-driven companies that spend more resources marketing themselves as being environmentally friendly than minimizing its footprint. We need to be discerning as consumers to avoid being misled. This may entail equipping ourselves with basic carbon literacy.⁶² As healthcare professionals, we should undertake a greater role in advocating for policies that support the emission reductions. Climate change is as much a health issue as it is an existential one.¹

Conclusion

Healthcare sustainability as an agenda has been nascent in the cardiothoracic fraternity. Being major stakeholders of complex surgeries with a high carbon footprint, we should pioneer efforts in reducing carbon emissions yet maintain quality care delivery in our practices. (Table 1) Addressing the triple bottom line both within and outside the operating theatre starts from awareness and education that will result in action. Akin to medical conventions in treating a disease, we first need to diagnose the problem with carbon audits and life cycle assessments, then move on to extinguish the identified hotspots. As the world rapidly wakes up to the threat of climate change, let us take charge both as advocates for our patients who directly suffer from the consequences of poor planetary health^{3, 7, 8, 12} and follow in the footsteps of our intrepid predecessors who dared challenge the norm and engender a culture of sustainability in cardiothoracic surgery.⁶³

Author contributions

Lowell Leow: Conceptualization; investigation; methodology; writing – original draft. John Kit Chung Tam: Conceptualization; supervision; writing – review and editing. Pei Kee Poh: Writing – review and editing. Amanda Zain: Supervision; writing – review and editing.

Conflict of interest

None declared.