Driving improvements through harm reduction

To help Great Western Hospitals NHS Foundation Trust (GWH) achieve its vision, the senior management team has set out the four ‘strategic pillars’ detailed in Figure 1, with the goal of driving improvements across the Trust. 

Figure 1. The four strategic pillars for Great Western Hospitals NHS Foundation Trust.

A key metric within the ‘outstanding patient care and quality improvement’ pillar is Total Harms, and the Trust target is to achieve zero avoidable harm within 5-10 years. The Trust’s calculation for ‘total avoidable harms’ aggregates monthly incidences of; pressure ulcers/harms; Falls; Hospital acquired infections (including COVID-19); Medication incidents; Serious incidents; Never Events.

Within ‘Total Harms’, pressure ulcers/harms acquired either as an inpatient or in the community at GWH, have been identified as the top contributor due to frequency and level of harm, therefore pressure ulcer/harms have been developed as one of three Breakthrough Objectives for the Trust in 2022/23. These Breakthrough Objectives are closely monitored by the Trust board and progress on these objectives is analysed at monthly board meetings. 

Effective pressure ulcer (PU) prevention and driving down PU incidence is therefore a top priority within the Trust and represents a key focus for all staff at every level within the organisation from ‘board to ward’.

Reducing PU incidence (harm) in a Critical Care Unit

In 2021, the team at GWH identified a persistent issue with patients developing pressure ulcers during their stay on the twelve bedded Critical Care Unit (CCU).

A review of the CCU pressure ulcer prevention and management care bundle highlighted that the standard mattress in use on the unit was a pressure redistributing foam mattress, however where necessary, the highest risk, most dependent patients would be provided with an alternating pressure air mattress (APAM).

Root-cause analysis by Tissue Viability and the CCU team identified that upon admission to the unit the delivery of urgent, life preserving patient care was prioritised over the provision of an appropriate pressure area care (PAC) support surface. This prioritisation of care could ultimately delay patients at the very highest risk of pressure ulcers from receiving the correct support surface by up to seventy-two hours.



The aim for Tissue Viability and CCU was to reduce pressure ulcer incidence (harm) by implementing a change in practice on the unit. 

The goal was to eliminate delays in support surface provision by adopting a single support surface strategy, where a single mattress could deliver optimal pressure area care for all patients from the point of CCU admission, irrespective of PU risk level and any urgent, life preserving care required. 



In early 2022, a new mattress system was evaluated on the CCU to ensure it met the pressure area care needs of the highest risk, most dependent critical care patients.

March 2022 saw adoption and implementation of eleven state-of-the-art powered hybrid support surfaces into the CCU pressure ulcer prevention and management care bundle. These new support surfaces, the OSKA Series6 OneSurfaceTM mattress (see Figure 2), replaced the previous high specification foams and APAMs used on the unit.

Figure 2. The OSKA Series6 OneSurfaceTM powered hybrid mattress.

Since March 2022, CCU admissions have been placed directly onto the Series6 OneSurfaceTM  mattresses and there has been no requirement for any additional APAMs within the unit.

To determine the impact of this change on patient outcomes, Tissue Viability and CCU teams compared the unit’s pressure ulcer incidence (harm) pre- and post-adoption of the new single support surface strategy.


Pressure ulcer incidence reduction

Between January and December 2021 thirty-one patients in the twelve-bedded CCU developed pressure ulcers during their stay on the unit and pressure ulcers (harms) were reported in nine of the twelve months during this time (see Figure 3).

In the nine months since adopting the new mattress into the CCU pressure ulcer care bundle, the CCU has reported eight harm-free months of zero pressure ulcers, with two patients (0.3%) developing Category 2 pressure ulcers in October 2022 (see Figure 3).

During this time, the eleven new mattresses have been used for more than 2950 CCU bed days, covering 575 patient admissions (311 male; 264 female). The primary diagnoses for patients admitted into CCU since March 2022 is varied and includes trauma; cancer; cardiac, surgical; spinal; stroke; and orthopaedic patients.

Pressure ulcer management

Since March 2022, 23/575, CCU admissions presented with existing PU (see Table 1). All twenty-three patients were successfully nursed on the mattress and no pressure ulcers deteriorated during the patients’ CCU stay.

Table 1. Patients admitted into the CCU with existing pressure ulcers since March 2022.

Staff views / product feedback 

Structured questionnaires were used to capture feedback on the Series6 OneSurfaceTM mattress, with CCU staff happy to use the mattress for:

• pressure ulcer prevention in patients at the highest PU risk-level.

• management/healing for all pressure ulcer categories.

Mattress performance was rated as 8.9/10 and mattress safety as 9/10. The mattress also received an ‘excellent/good’ rating for; shear management; microclimate management; patient comfort; product quality, reliability, and ease of use.



It is essential for all GWH staff to work together to identify areas of greatest concern and implement effective change to improve outcomes in line with the Trust’s vision. Where Total Harms are concerned, it is driving towards zero avoidable harms, and specifically a reduction in PU incidence (harm) which has been identified as one of the Trust’s three Breakthrough Objectives for 2022/23.

Identifying and implementing changes to improve patient outcomes can affect policy, process, products, or a combination of these. 

Identifying the underlying issues behind the high level of PU incidence reported on the CCU resulted in changing both process (eliminating protracted delays in APAM provision for the highest risk patients) and product, to effectively drive down CCU acquired pressure ulcer harm to the lowest practical level.

Adopting a single support surface capable of meeting the PAC needs of all CCU patients has eliminated any delays in mattress provision and thereby addressed the root cause of the high level of PU incidence reported on the CCU. Utilising a single mattress throughout the CCU ensures that optimal pressure area care and the immediate delivery of urgent, life preserving patient care within the CCU are no longer mutually exclusive and, where necessary, can occur simultaneously upon admission to the unit. 

As illustrated in Figure 3, this change in practice, to deliver optimal pressure area care immediately and without delay, to one of the highest risk, most dependent patient cohorts has resulted in a significant reduction in pressure ulcer (harm) incidence within the CCU.

In addition to supporting the reduction in PU incidence within the CCU, the mattress was also effective in managing patients admitted into the CCU with existing pressure ulcers. It also evaluated well with the staff who have used it.



By working together, Tissue Viability and the CCU team uncovered the problem, identified the root cause, and proposed and implemented a viable solution which resulted in reducing PU incidence (harm reduction) towards zero, thereby supporting one of the Trust’s three Breakthrough Objectives.

Whilst it is important to acknowledge that this work focused on a relatively small, highly specialised clinical area and may not be applicable to all areas of GWH, it clearly demonstrates what can be achieved from a quality improvement perspective when working collaboratively to improve patient outcomes in one of the highest risk, most dependent patient cohorts anywhere in the Trust.