A virtual ward bed uses 4 times less carbon than a traditional inpatient bed, so helping the NHS achieve its net zero target by 2045, finds the first study of its kind, published in the open access journal BMJ Innovations.
And they are a promising way to care for more patients effectively, with the potential to reduce the need to build more high-carbon impact hospitals, suggest the researchers.
A virtual ward, also known as "hospital at home," provides hospital-level care to patients in the comfort of their own homes, leveraging digital technology and remote monitoring.
In recent years, particularly in the wake of the COVID-19 pandemic, virtual wards have been widely adopted throughout England to ease pressures on hospital bed capacity and streamline patient flow, say the researchers.
But while existing research has primarily focused on the care outcomes and cost effectiveness of virtual wards, few studies have looked at their environmental impact and carbon footprint.
To plug this knowledge gap, the researchers compared the carbon cost of virtual ward care with that of traditional inpatient care between May 2022 and May 2023 in a large acute hospital trust.
They quantified the avoided carbon emissions for 1260 virtual ward patients, 728 of whom were frail and 532 of whom had an acute respiratory infection.
The researchers used the Greener Care at Home toolkit to calculate the carbon emissions of a care pathway, including carbon activity points, such as accident and emergency (A&E) attendance, travel to hospital in an ambulance/car, and diagnostics.
All inpatient bed days, virtual ward bed days, home energy and community/general practice (GP) call-outs were calculated initially for a random sample of 30 patients, using a manual audit and then for the entire group of 1260 patients, using an internal data collection system.
The researchers used a previously created method to calculate 'predicted stay' in hospital for the virtual ward and traditional inpatient care pathways.
The results show that there was a significant difference between the carbon costs of a virtual ward and an inpatient stay, with virtual wards emitting significantly less carbon when evaluated across the entire episode of care.
On average, an inpatient bed emits 4 times more carbon at 37.9 kg CO2 than a virtual ward bed day at 8.8 kg CO2. And avoided carbon emissions added up to 285 tonnes of CO2 between May 2022 and May 2023.
This doesn't represent a carbon reduction for the hospital, emphasise the researchers, as hospital beds were still in use by other patients, but it does represent increased capacity.
And the reduced carbon footprint of virtual wards is particularly important as the NHS aims to deliver 40–50 virtual ward beds per 100,000 of the population, say the researchers.
"Having a [virtual ward] in place will not decrease overall carbon emissions for the hospital but enable more patients to be cared for in the most efficient and lowest carbon way possible, enabling the hospital's capacity to increase and for teams to manage more patients with the same number of inpatient beds," they write.
Carbon costs were higher, using the manual audit, largely due to the addition of external factors that internal hospital data systems don't capture, note the researchers.
The researchers acknowledge that they didn't have any data on carbon emissions from typical home use, and relied instead on government calculations, which estimate average home carbon emissions of 7.4 kg CO2/day. Nor do patients always fit into a neat box of a mapped pathway, which highlights the complexity of carbon mapping care pathways, they point out.
Nevertheless, they conclude: "[Virtual wards] look like a promising way for hospitals to increase capacity in a model of sustainable healthcare that aligns with the triple bottom line analysis of high-quality care, value for money, and low associated carbon emissions."
They add: "We know that a traditional inpatient bed is a very high carbon/resource intensive method of treating patients. As our population increases, we will need to create more effective, less resource-intensive ways to treat our local population, without having to build more hospitals as this is extremely high cost, high carbon, and will require additional workforce."
