4 Committee discussion

Clinical effectiveness overview

Prontosan shows promise but there is not enough evidence of its clinical benefit

4.1 The committee noted that much of the evidence comparing Prontosan and saline in treating chronic wounds had some concerns or was at high risk of bias. The committee noted that there was very limited evidence for acute wounds. The committee agreed that the technology showed promise based on clinical expert advice, but that this was not supported by the evidence. The committee concluded that there was not enough good quality evidence to make a clear judgement about the benefits of Prontosan compared with saline or water.

The evidence is heterogeneous in terms of wound type

4.2 The committee noted that the patient populations in the evidence were heterogeneous, including different wound types such as venous leg ulcers, chronic wounds of mixed aetiology, burns and surgical site wounds. The clinical experts agreed that Prontosan could be used for a broad patient population. Some experts suggested that chronic wound management approaches are likely to be similar in the basic principles of dressing management, despite differences in the underlying causes and treatment. Nevertheless, the committee understood that there is a diversity of wound types in the chronic wound population and that it is difficult to generalise the evidence from the trials to the total population with chronic wounds. Ideally, further evidence is needed to detect clinically meaningful results in specific wound types (for example, pressure ulcers or venous leg ulcers).

How Prontosan products are used in the studies varies but this is likely to reflect NHS practice

4.3 The committee noted that how Prontosan products were used ranged across the studies. Prontosan solution was used alone, with the gel or gel X, or the gel or gel X were used alone. The clinical experts agreed that the choice of Prontosan product used depends on the wound and the person's situation. The clinical experts said that the Prontosan solution is used as a soak for chronic wounds. Soak times can vary between 5 and 15 minutes depending on the wound condition and size. Guidelines recommend using cleansing solutions such as Prontosan during dressing changes. For example, during consultation, the committee was made aware of the National Association of Tissue Viability Nurse Specialists (Scotland) wound cleansing pathway which recommends: 'if the wound is chronic, infected, have debris or residual dressing in place OR if the patient is at high risk of wound infection, consider using a biofilm disrupting cleansing solution'. The committee also noted that the National Wound Care Strategy Programme's lower limb recommendations recommend cleansing the wound bed at each dressing change. The clinical experts noted that the gel is used less often, and almost always in combination with the solution to support and maintain the soak process. The clinical experts said the gel is most often used for more complex and chronic wounds and for people with a history of recurrent infections. The clinical experts agreed that both the solution and gel have the same ingredients and should be considered the same product. The committee recognised the heterogeneity in the way the Prontosan products were used but concluded there may also be differing approaches used in the NHS.

Prontosan has plausible benefits

4.4 The clinical experts noted that, in their experience, using Prontosan on static (non-healing) chronic wounds with a dull brown colour causes the wound bed to change to vibrant red granulated tissue (tissue in the process of healing). No adverse events or allergic or instant reactions to Prontosan were observed by the clinical experts. The clinical experts said that Prontosan is easy to use, soothing and does not sting. The committee recognised that patient reported outcomes such as pain and odour are important considerations when treating chronic and acute wounds and concluded that Prontosan has plausible benefits.

Outcome measures

Complete wound healing is the preferred outcome

4.5 The clinical experts said that they would use Prontosan when clinically indicated, typically until the wound bed was completely clean and looking healthy and epithelised (when a layer of new tissue forms over the wound). The clinical experts clarified that wounds can epithelialise and close, but this does not mean the wound is healed. For people with a history of recurrent infection, the wound can break down again if treatment is stopped before the wound is healed. Some types of chronic wounds, specifically leg ulcers, often deteriorate and recur. To measure Prontosan's effectiveness compared with saline, the committee concluded that evidence is needed that follows wounds until they are completely healed. This evidence should also measure the time it takes for complete healing to happen.

Improved wound bed condition is an important outcome

4.6 Chronic wounds can be complex and may become static or have high levels of recurrence. The clinical experts noted that some people have wounds for several years and some may never heal. The experts agreed that improved wound bed condition is an important outcome. Wounds move through different stages of healing. Unless the wound bed is prepared through debridement, removing slough and clearing biofilm, the wound becomes stagnant and cannot heal. Improving wound bed condition has the potential to improve quality of life because it may reduce odour, exudate, pain or result in fewer dressing changes. The clinical experts noted that it is difficult to robustly measure wound improvement. However, validated quality of life tools should capture aspects of wound improvement. The committee considered that improved wound bed condition has an important place in wound care, particularly for some people who have long-term chronic wounds that do not heal within 12 months.

Uncertainties in the reporting of the BWAT score from Bellingeri 2016

4.7 The most robust evidence (a randomised controlled trial by Bellingeri 2016) was at low risk of bias but underpowered based on the statistical analysis plan. It showed a significant reduction in Bates-Jensen wound assessment tool (BWAT) score for Prontosan compared with saline. The external assessment centre noted that it is unclear from the study whether all 13 dimensions of the tool were used. It was not confident that a reported BWAT score of 13 or 14 in this paper can be interpreted as wounds that have healed, or that are approaching healing.

Relevance to the NHS

The evidence from Bellingeri 2016 may be generalisable to NHS practice

4.8 The clinical experts said that they had not used the BWAT score in NHS practice. However, they agreed that it is a comprehensive wound assessment tool. They said most of the factors in the BWAT, including state of wound bed, wound size, sign of infection, pain, exudate and type of dressing, are part of wound assessment tools used in the NHS. However, clinical experts also noted that there are no universally agreed wound assessment tools. The committee concluded that the BWAT is likely to reflect clinical assessments of wounds and may be generalisable to other wound assessment tools used in the NHS.

NHS considerations overview

Prontosan does not add to the appointment time if the soak is applied at the start of the appointment

4.9 The clinical experts told the committee that Prontosan solution is often applied as a soak (for 10 to 15 minutes) for chronic wounds. The experts noted that this can lead to an increase in appointment times in some cases (primarily wound clinics) but that if the tasks are switched around and the soak is applied at the start of the appointment this should not extend the appointment time. The committee concluded that some education and training may be needed to ensure healthcare professionals know to soak with Prontosan solution at the start of an appointment.

Prontosan is part of a wound care package, so the treatment effect is hard to establish

4.10 The committee noted that Prontosan is part of a wound care package and almost uniformly not used on its own. This means it is difficult to isolate the treatment effect of Prontosan on chronic wounds. The clinical experts stressed the importance of using a locally agreed wound care pathway and explained that treatments are selected using a holistic approach and clinician experience. People with chronic wounds do not necessarily see the same clinician, and use of products and dressings can vary between visits based on what is available. One clinical expert said it would be easier to use one solution consistently rather than decide between multiple solutions (water, saline or Prontosan). Examples of local wound care pathways where Prontosan had been implemented were provided during consultation. The committee concluded that it is hard to isolate the direct effect of Prontosan and recognised the need for an appropriate wound care pathway for chronic wounds.

Cost modelling overview

The cost models are acceptable but any cost modelling using the available evidence is likely to be flawed

4.11 The committee agreed that the clinical and cost case were dependent on each other. Prontosan would result in cost savings even if there was only a small benefit in healing rate or reduction in infection rate. The clinical inputs in the model had some concerns or were at high risk of bias. They were also subject to the same uncertainty as discussed in the clinical evidence section. The committee concluded that more research was needed to establish the clinical and cost benefits of using Prontosan in the NHS. Until then, any cost modelling is likely to be flawed.

Further research

Randomised controlled trials comparing Prontosan with saline or water in the NHS are needed

4.12 The committee concluded that further research is needed to address the uncertainties about the clinical effectiveness of Prontosan compared with saline or water. It recommended that randomised controlled trials should be done in the NHS. These should compare Prontosan with saline or water in different types of chronic wounds. The randomised controlled trial needs to be well designed to detect clinically meaningful results in subgroups (for example, pressure ulcers or venous leg ulcers). The committee agreed that a key outcome should be time to complete wound healing. The number of dressing changes should also be recorded for each wound included in the study. Other important outcomes should include pain and wound odour, measured using patient-reported outcome measures (PROMs).