Sensor-based monitoring paying off at St George’s

Located in Tooting, St George’s Hospital dates back over 200 years. It opened its doors as a 60-bed hospital at Hyde Park Corner in 1733, and was rebuilt in 1820, offering over 300 beds. To help meet a growing demand, a new convalescent hospital was eventually built in Wimbledon, and a new medical school, now known as St George’s, University of London, was established on the St George’s Hospital site in 1868.¹ The University moved to its current site in Tooting in 1976, and was followed by the hospital, which finally closed its Hyde Park Corner site in 1980.

Each year, over 130,000 operations are performed at St George’s Hospital on patients from across the South of England in its state-of-the-art operating theatres. It has 31 theatres, including seven cardiac and neurosurgery theatres in its Atkinson Morley Wing. Here, over 4,000 of the most complex neurosurgical and cardiothoracic procedures are undertaken each year.²

The need for monitoring

Operating theatres are large energy consumers, accounting for a high proportion of hospitals’ carbon footprint. According to the UK Health Alliance on Climate Change (UKHACC), they are three to six times more energy-intensive than clinical wards.3 Most theatre energy consumption relates to maintenance, such as of heating, ventilation, and air-conditioning (HVAC). Meanwhile, lighting and medical equipment such as anaesthetic gas scavenging systems (AGSSs) are also high sources of consumption.

An operating theatre’s environmental conditions can influence the clinical process and a hospital’s environmental, social, and governance (ESG) performance. For example, temperature, humidity, CO2, and occupancy, are all influential factors.

In recent years, the NHS has begun to embrace the expertise available from small- and medium-sized enterprises (SMEs), particularly when implementing strategies to digitally enable its estate. This includes seeking the specialist services needed to safely extract data sources from legacy systems.

St George’s competed with several organisations for sustainability funding from its local authority. Eventually, it won the entire allocation after submitting a project based on its ‘smart’ theatres. The team wanted to capture all the available data from 31 operating theatres across St George’s, and augment any missing data sets by adding control and monitoring devices where required. Although the scheme was largely supported by SW London ICB green funding, it was driven by NHS Estates and supported by NHS England.

Meanwhile, IAconnects had been chosen by a team working on behalf of the NHS, led by academics from Loughborough University, to provide condition monitoring and digital advisory services to a research programme looking at hospitals affected by reinforced autoclaved aerated concrete (RAAC). As well as supplying and testing automated condition monitoring device options, we needed to understand how existing data sources could be collected, aggregated, and channelled, into academic research programmes. After an 18-month engagement, our involvement with the programme was complete, having contributed significantly to stakeholders’ understanding of the risks associated with RAAC and possible management tools.

The NHS followed this successful project delivery, which was achieved thanks to a specialist partner eco-system. Subsequently, it chose us to provide data capture, aggregation, and dissemination services to St George’s as part of its recently-funded smart theatres project.

Getting started

Having been recruited for the smart theatres project, we started by spreading the project across several domain experts, which included Siemsatech, a BMS specialist, and a consultancy called SRO Innovation, which it had collaborated with for several years. This ecosystem also included BIM and digital modelling specialists who would offer their expertise.

We then carried out 6-12 months of investigative works, identifying areas where we thought optimisation could be achieved, and that we could monitor. This step was crucial for understanding the parameters that would influence the workings of the theatre environment. We started by looking at the BMS and unpacking a range of things: what metering was in place, what air quality metrics the hospital used, how the BMS operated, how it monitors air pressure and filtering, and more. This deep dive was important, and, once we’d identified the gaps, we could start looking at what sensor technology we could deploy to fill these. As expected, not much data was available from the BMS, and what we did have was unreliable, so the list of sensor technologies required increased immensely.

Varying degrees of connectivity

There are 31 operating theatres inside St George’s, which have been delivered and grown over 30+ years with various types of technology. These all have varying degrees of connectivity and data, so even if we could access it, this information probably wouldn’t have been all that useful.

Phase one of the project was about establishing connectivity with the existing BMS, to establish a collaborative network, with the new technology acting as a digital overlay. This meant that any actions from what the sensors were monitoring would trigger a change in 
the BMS, ideally without human intervention. Consequently, establishing safe connectivity meant engaging with the Trust’s IT team and identifying a suitable network. We then looked at wireless technologies, eventually providing over 500 wired and wireless sensing devices that ran using a Long Range Wide Area Network (LoRaWAN) protocol. Again, this required approval from ‘IT’, and proof that the technology wouldn’t interfere with anything clinical on site. We also had to establish network points, ensuring connectivity via a virtual local area network (VLAN).

From the start, the project enjoyed clinical engagement, which was crucial. As well as project managers and other built environment stakeholders, we had regular input from clinicians, surgeons, nursing leads, infection control, and anaesthesia — the list is almost endless.

Their insights were key when looking at what metrics to capture using the wireless sensor technology. For example, we didn’t realise that some procedures, like hip replacements, are optimised for certain temperatures and conditions. Naturally, this would cause an inconsistency in readings across the hospital, so we needed to be aware.

Trusted advisors

“The team at IAconnects Technology have become trusted advisors and suppliers in support of the St George’s Hospital Digital Roadmap,” said David Roskams, Building Your Future Hospitals lead for Digital Transformation, Estates and Facilities Division, at St George’s Hospital. “IAconnects’ approach is always pragmatic, and — at every step – it considers the bigger picture. It operates comfortably in all aspects of what is a highly complex business model, considering not only digital and asset management challenges, but adding value to clinical, EFM, and business intelligence working groups.”

With the LoRaWAN sensors installed, the hospital’s team now had over 250 data points from the BMS, providing the user interface and analytics for eleven Trust stakeholders. Captured datasets included temperature, humidity, CO2, TVOC (Total Volatile Organic Compounds), illuminance (Lux), air pressure, and air change rates. Data was also collected on occupancy, which was a trigger for the BMS Set Back and Ramp Up. Meanwhile, power was monitored using a combination of wireless current transformers and BMS-derived data.

Our team ensured that any data captured would be available to the NHS and the Academic Industry Partnership (AIP) at Loughborough University. This meant that the University’s Data Science team could take any or all of the sensor data and analyse the information from the operating theatres. We achieved this accessibility by running a middleware platform, MobiusFlow, that collects, normalises, and aggregates data sets. The platform effectively made the data flow bi-directional with the existing BMS, with wireless data coming from the new sensors, energy consumption data from metering, and BMS data from the HVAC.

Now monitoring around 1,500 data points across the hospital, we needed a way of visualising this information, so we built a platform that would offer different user personas for the various stakeholders. This meant, for instance, that Sustainability managers would have one view of the data, and ESG managers another. Meanwhile, the Estates team would have multiple views, since the department may be interested in a range of parameters. To further improve visibility, automated links were also added, meaning that when a fault appears on the system, it will auto-generate, and appear on stakeholders’ computer-aided facility management (CAFM) system.

Energy and asset optimisation

With the new system now in place across the 31 operating theatres, the hospital is already seeing the benefits of having the wireless sensors and a more sophisticated process for data aggregation. The cumulative project value for us was circa £150,000 and, in total, it had a value of around £850,000 for the Trust.

Based on spend, an ROI is expected in less than two years — and that’s just for the project’s first phase works that have been completed so far. It is also estimated that, in year one, the project will save the hospital over £350,000 in energy savings alone — a significant benefit for an NHS hospital under pressure to improve efficiency and cut costs.

As well as lowering costs, optimisation has had a positive effect on asset health. The motors, drives, inverters, and control equipment in the BMS are now under far less stress, because we’re pushing setback modes into the theatres.

Based on our sensors’ understanding of occupancy, and what they classify as occupational time, we’re changing the mode for the systems that supply the theatres with air, heating, and cooling. Over time, this will help extend the asset lifecycles, as they’re being used less frequently, and only when needed.

The next phase

The team at St George’s recently secured additional funding from the New Hospital Programme (NHP) for Phase Two works. These will involve expanding the network of sensors into the feeder rooms for the main operating theatre, primarily anaesthesia. As part of this process, we are investigating nitrous oxide monitoring in these rooms, along with the function of the AGSSs. Scavenger gas systems can be inefficient, and will sometimes be running 24/7 if staff forget to switch them off. These machines are big energy consumers, because they constantly run pumps, compressors, and motors, meaning that a system optimisation process could deliver significant benefits.

Meanwhile, the hospital is running some projects to help it understand how it could use AI for things like predictive failure and optimisation. It is also identifying how it can overlay environmental and patient data for retrospective analysis. This means that if something were to go wrong, the hospital could track the patient’s journey before they entered the theatre. This goes back to them leaving the house, and includes the many stages before returning home.

The NHP is very engaged in the project, and is using the information from the optimisation to help shape the new hospital model. In theory, all the tools we’re retrofitting, and the connections we’re establishing, should be baked into the new hospital model — and this will help the NHS on its digitisation journey.

References

1 St George’s Hospital [Internet]. St George’s University Hospitals NHS Foundation Trust, 2024. https://tinyurl.com/bdfrfxh7

2 Theatre nursing and operating department practitioner jobs at St George’s [Internet] 2024. St George’s University Hospitals NHS Foundation Trust. https://tinyurl.com/3pfksn2s

3 UK Health Alliance on Climate Change. Sustainable healthcare: Green surgery — Reducing the environmental impact of surgical care. Report [Internet]. UK Health Alliance on Climate Change, 2024. https://tinyurl.com/bdya87n4