What would happen if you installed a button in the operating theatre that allowed the surgical team to determine for themselves, at the touch of a button, how much air is supplied to the operating theatre during a specific operation? A little more air during infection-sensitive procedures, a little less during all other operations.

Would the person performing the operation, and therefore responsible for the medical treatment, be inclined to choose the maximum amount of air to rule out any possible risk to the patient? Or has the standard way of working in the Netherlands become so strict over time that the air treatment system could really be turned down a notch without putting the patient at risk in any way?

This button is not fiction but is already in use in some Dutch operating theatres and is being considered in other hospitals. More on this later, but first an outline of the impact of healthcare on the environment and climate and the conclusions of the recently published report by the Groene OK.

Goody two shoes

Air treatment expert Jos Lans and physician-researcher Egid van Bree, two of the seven authors of the report, hope that their research will contribute to measuring and reducing the environmental impact of healthcare. And that impact is enormous: worldwide, 6% of total energy consumption in buildings takes place in medical centres. Within these centres, operating theatres consume a lot of energy, with more than 90% of that energy being used for air treatment. In short, energy savings on air treatment in operating complexes can result in significant CO2 reductions.

Remarkably, the air treatment systems in many Dutch hospitals appear to be set considerably higher than the standards prescribe. The amount of fresh outside air that is blown in is also much higher than in many other European countries.

Jos cautiously states: ‘You could say that it seems as if the Netherlands is clinging to outdated guidelines for too long. The amount of fresh outside air that must be blown into an operating theatre is around 800 m³ per hour in Switzerland, for example, while the study shows that this is currently around 2700 m³ per hour on average in the Netherlands. The temperature and relative humidity of this air must always be brought within the required target values.

In addition, the majority of Dutch hospitals use what is known as ‘laminar flow’: a column of relatively cold air that descends directly above the operating table and keeps the air there as clean as possible. Egid: ‘These are energy-intensive systems, while the WHO guidelines question their added value. This has not been investigated for most operations.’ That is why, according to him, critics argue that the current way of working is partly the result of years of blindly adopting technical innovations.

Scientific basis

Rather than discussing a possible explanation for why air treatment in Dutch operating theatres has been ramped up so much, Jos and Egid talk about the change that needs to be made.

Not only about how to get doctors, technicians and hospital administrators on board, but also about how much scientific evidence is needed to convince everyone.

Egid: ‘It's largely about preventing wound infections. That's very difficult to investigate because many other factors influence this, such as the patient's condition, whether they are obese, for example, and the behaviour of the staff in the operating theatre.

Above each operating theatre is a floor with enormous installations. These ensure that recirculated indoor air and fresh outdoor air are filtered, heated, cooled, humidified or dehumidified and blown into the operating theatres by fans. The more often the air in the operating theatre is changed per hour, the fewer dust and bacteria particles in the room, the faster the air quality in the operating theatre recovers after a disturbance.

In addition to preventing wound infections, cooling the operating theatre and diluting the surgical smoke released during an operation are also determining factors for the amount of air that needs to be blown into an operating theatre. Still, according to the researchers, the latter can be achieved more effectively by ‘spot extraction at source’.

Savings of up to 50%

In its new report, De Groene OK concludes that in Dutch practice, almost all operating theatres meet the strictest possible requirements, even though this is by no means always necessary for most operations. In the Netherlands, air humidity is also often kept within too narrow a margin, while previous research has shown that it can be more generous.

Dutch hospitals are already taking measures to reduce the energy consumption of air treatment systems in operating theatres. For example, they use heat recovery systems and 80% of the hospitals participating in the study set the air treatment to a lower setting at night and at weekends. However, De Groene OK concludes that in almost all hospitals, a lot of energy and therefore money is still being wasted.

Egid finds the possibility of saving up to 50% energy by bringing in proportionally less outside air to be the most surprising finding. However, this can only be adjusted if the hospital has a system that can regulate this separately. In some cases, this requires reducing the total amount of air, which means that the operating theatres will no longer meet the strictest requirements for joint replacement surgery.

Financial incentives

According to Egid, one of the elements of a successful formula for energy saving in hospitals is multidisciplinarity: ‘The picture emerging from my PhD research is that the hospitals that are achieving results have a fixed consultation structure between the heads of technology, operating theatre management and infection prevention. They must consult with each other regularly so that they can better understand each other's perspectives. Relevant knowledge and expertise are needed, as well as the will to change.'

He also believes that linking financial incentives to the initiative can help. Egid: ’Some sustainability initiatives generate money, but if they are somewhat unpleasant for people on the work floor because they have to give something up or make more effort, they often want to see something in return. The money saved should not disappear into the hospital's coffers.' In some hospitals, the money saved on energy is therefore used to fund other sustainability initiatives.

Elles Tukker

Button or no button?

Back to the climate button. The success of something like this naturally depends on the willingness of employees to use it. Frenk van Harreveld, professor of Social Psychology at the University of Amsterdam: ‘Whether that is the case depends, among other things, on how important people consider sustainability to be. In the context of healthcare, that is not yet self-evident. We often hear that in the context of life and death, sustainability is considered secondary.

According to Frenk, ease of use is also an important factor: ‘Pressing a button is an extra action. The easier it is to use, the more people will be willing to accept this extra action. Research into the behavioural component can provide insight into factors determining the success of something like a “climate button”.

Amsterdam UMC makes a different choice

One of the hospitals that has been working for some time to make the air treatment in the operating theatre complex more sustainable is Amsterdam UMC. Physician-microbiologist and Circularity Programme Manager Ingrid Spijkerman: ‘We have already saved a lot of energy by reducing the air treatment in the evenings, at night and weekends. We have also broadened the humidity range. The multidisciplinary project group is currently investigating the extent to which we could reduce the fresh air supply and how we could adjust the air treatment in the system for each procedure.

Ingrid explains why Amsterdam UMC is not in favour of a button in the operating theatre: ‘We must avoid individual healthcare providers making this decision for each operating theatre, as this could lead to human error. We are now investigating a link whereby the air treatment is automatically adjusted to the operation taking place. And every step we take in this process is first submitted to all stakeholders involved in the operating theatre.'

Elles Tukker