Sustainable solutions to replace anaesthetic gases in the NHS

2nd March 2022

Recognising climate change’s threat to health, the NHS has become the world’s first healthcare system to commit to reaching carbon net zero by 2040. As a result, the Academic Health Science Network for the North East and North Cumbria (AHSN NENC) is working with partners across a range of disciplines to support the delivery of innovative sustainability solutions.

In this blog, Dr Sean Gill reflects on programmes of work the AHSN NENC is supporting to reduce the impact of anaesthetic-generated emissions, which are responsible for over 2% of all NHS emissions.

Since joining the AHSN NENC a year ago, I’ve been very fortunate to be involved with an exciting and growing programme of work supporting environmental sustainability in healthcare, including the impact of anaesthetic gases.

Background to anaesthetic gases

Anaesthetic gases are commonly used as a part of everyday surgeries across the NHS. However, following use, they are expelled into the atmosphere, where they contribute to climate change.

To help combat this problem, the NHS Long Term Plan has committed to lowering the NHS’ carbon footprint from anaesthetic gases by 40%. This requires efforts to shift from desflurane to lower carbon alternatives such as sevoflurane, which in turn has a number of benefits including: effective capture, destruction or reuse of these gases; and reduction in the atmospheric release from leftover nitrous gas canisters.

For example, anaesthetic gases used in surgery, such as desflurane, have a particularly high carbon footprint, with the emissions from one bottle equivalent to those from burning 440 kg of coal. However, low carbon alternatives exist, and are clinically appropriate in a wide variety of settings. Engagement with anaesthetists has seen a significant cut in some anaesthetic gas use since 2018, with monthly volumes of some volatiles falling by nearly 50%, saving 17 kilotonnes of carbon dioxide equivalent (ktCO2e) per year. With further clinical engagement, it could be feasible to reduce the use of desflurane to as little as 5% by volume, saving a further 23 ktCO2e per year.

Further, the capture and destruction of nitrous oxide could cut over one-third of NHS anaesthetic emissions. This technology has been readily deployed in Sweden for some 16 years and could save an estimated 90 ktCO2e emissions if implemented across 132 high impact trusts in the NHS. Scaled across the entire health service, this could deliver up to a 75% reduction in nitrous emissions. Similar technologies for anaesthetic gases went to market in 2020, following successful trials in UK hospitals, with funding from Innovate UK.

Finally, significant carbon savings are available by decreasing nitrous oxide wastage, with the College of Paramedics estimating that 30% of nitrous oxide is left in canisters after use. Recycling or reusing this is technically difficult, with new methods required to address the residual nitrous oxide.

Below, I’m sharing two real life examples of how we’re striving to make local care services more sustainable by fostering collaborations between industry and healthcare.

Climate-friendly pain relief during childbirth

With support from the AHSN NENC, The Newcastle upon Tyne Hospitals NHS Foundation Trust has been working with innovators at MedClair, to trial their climate-friendly technology at Newcastle Birthing Centre.

MedClair is a Swedish research and development company with leading edge expertise in the measurement, collection and destruction of nitrous oxide. They have developed the Central Destruction Unit (CDU) and Mobile Destruction Unit (MDU), which purifies over 99% of the nitrous oxide entering the unit. This facilitates a safe working environment for doctors, nurses, midwifes and other professionals.

Using this technology, one mum from Newcastle, Kaja Gerinska, became the first person in the UK to use climate-friendly pain relief during labour at the Newcastle Birthing Centre. Kaja breathed the gas and air into a Mobile Destruction Unit (MDU) – a machine designed to collect and destroy residual nitrous oxide from exhaled gas and air. The technology, developed by MedClair collects the exhaled nitrous oxide, a potent greenhouse gas and ‘cracks’ it into nitrogen and oxygen which are harmless. Read about this innovative pilot project in more detail.

Environmentally friendly anaesthetic face masks

The AHSN NENC are working with SageTech Medical to develop a patient mask to be used in hospital recovery suites that supports the reduction of carbon footprint in the NHS and protects staff.

The mask is connected by a breathing tube to a capture rig which incorporates SageTech’s canister-based capture technology. The system aims to capture all the drug exhaled once the patient has been disconnected from the anaesthetic machine. Through innovative design, the device will monitor the canister capacity and feedback to the clinician, providing alerts when the capacity is reached. The mask solution offers further protection to staff by reducing the transmission of infectious respiratory diseases.

The waste anaesthetic collects into SageTech’s reusable capture canisters which when full, are transported to an extraction facility hub. At the hub, the gases collected are extracted from the capture canisters and bulked up for shipment to SageTech’s purification facility. SageTech has developed technology to recycle the collected waste anaesthetic gas ready for re-use by the NHS and other healthcare providers, saving both money and reducing the harmful effects of volatile anaesthesia on the environment.