The economic benefits of negative pressure wound therapy in community‐based wound care in the NHS

Abstract

The human and economic costs of wounds are of major concern within today's National Health Service. Advances in wound care technology have been shown to be beneficial both in healing and in relation to patient quality of life. Negative pressure has often been associated with high‐cost care and restricted to use in the secondary care setting. There is growing use of negative pressure within the community, and this has the potential to benefit the patient and the service by providing quality care in the patient's home setting. Three community sites were chosen to monitor their use of negative pressure wound therapy (NPWT) over a period of 2 years, and this paper presents some of the key findings of this work. The data generated has been used to help target resources and prevent misuse of therapy. Cost per patient episode has been calculated, and this can be compared to similar costs in secondary care, showing significant savings if patients are discharged earlier from secondary care. There is also an increased demand for more patients with complex wounds to be cared for in the community, and in the future, it is likely that community initiated NPWT may become more common. Early analysis of the data showed that the average cost of dressing complex wounds would be significantly less than using traditional dressings, where increased nursing visits could increase costs. There is a compelling argument for more negative pressure to be used and initiated in the community, based not only on improved quality of life for patients but also on the economic benefits of the therapy.

INTRODUCTION

This article discusses the use of negative pressure wound therapy (NPWT) in community health care, in the light of current National Health Service (NHS) priorities, incorporating resource use data from three primary health care provider organisations in the UK.

The human and economic costs of wounds

The NHS is faced with the biggest challenge in its history, as a recent White Paper explained (1). Increases in the prevalence of chronic disease, combined with extended life expectancy and increasing expectations, have led to a continuing escalation in demand for health care (2). At the same time, it is recognised that the quality of health care cannot be allowed to decline, and, therefore, must be subject to continuous improvement. The challenge faced by the health care system, and of course faced by practitioners within it, is to improve the quality of care in an environment where the available resources are unlikely to keep pace with increasing demand.

Within the UK, the human and economic costs of wounds are significant and impose a considerable burden on the NHS. Two point prevalence audits estimated that there were 3·55 and 3·7 patients with at least one wound per 1000 covered population 3, 4. Across the UK, the annual cost of managing and treating wounds is considerable – the cost of treating chronic wounds alone in the UK has been estimated to be £2·3–3·1 billion annually (5). This includes £168–198 million attributed to leg ulceration, £300 million for diabetic foot ulcers and £1760–2640 million for pressure ulcers. The cost per patient episode of treatment for chronic wounds can be substantial – for example, in 2004, Bennett et al. (6) estimated that the cost of an episode of Grade 4 pressure ulceration was approximately £10 500.

Typical drivers of cost in wound care include the necessity to change dressings on a regular basis, the duration of treatment required and the incidence of complications. Changing wound dressings involves both materials and labour cost, and especially if nursing staff have to change dressings in patients' homes, is an important component of the overall cost of wound care. The choice of dressings is important because although the cost of the dressing materials themselves may not be a high proportion of the total, their influence on subsequent healing and complications may be considerable. Clearly, the time a wound takes to heal has an impact on resource use, and wound complications such as infection can have serious consequences and may result in hospitalisation or surgical interventions such as debridement, grafting or limb amputation.

Over the last four decades, advances have been made in both wound care products and the practice of wound management. As a consequence, many wounds can be treated using fewer resources than was previously the case, at the same time providing a better quality of care. For example, the use of advanced wound care products with superior exudate management means that the frequency of dressings change can be reduced (7). Patients therefore experience less exposure to external contaminants and less disruption to the healing process. This reduction in the use of materials and labour leads to associated economic benefits. As a result, nursing time can be freed up to be spent on other activities, leading to increased productivity.

To complement advanced wound dressings, technologies such as NPWT have been developed to improve the quality of care for wounds that may be particularly difficult to manage. NPWT has become widely used for the treatment of many different wound types, and there is now a considerable body of literature published 8, 9, 10, 11, 12 to support its use in different wound types. Additionally, the development of different wound fillers has provided a variety of options that can be used according to the wound type and therapy goals. A best practice statement was produced to support the use of gauze‐based NPWT (13).

Some of the published work includes information about resource use and cost. For example, Vuerstaek et al. conducted a randomised controlled trial comparing NPWT with modern wound dressings for the treatment of chronic leg ulcers in hospitalised patients. The median time to complete healing was 29 days in the NPWT group, compared with 45 days in the control group (P = 0·0001), and the time to wound bed preparation was shorter for the NPWT group (7 versus 17 days, P = 0·005). The costs in the NPWT group were lower than for conventional wound care ($5452 versus $3881, P = 0·001).

The case for NPWT in community health care

NPWT systems have in the past found most use in the hospital setting. However, the technology has now developed to the point where smaller devices have become available, allowing patients to be discharged from hospital with the NPWT pump and managed in community care. This is a considerable step forward for NPWT for two reasons. First, and most importantly, it means that the quality of life of patients can be improved, since they can remain at home whilst still being on NPWT. Second, it has the potential to allow earlier discharge from hospital thus freeing up hospital beds and resulting in reduced treatment costs. The treatment of patients in the community rather than the acute setting, and the subsequent reduction in the use of resources, continues to be high on the priority list of the NHS (14).

Three distinct economic benefits can be envisaged when patients are treated using NPWT in community health care:

• •Earlier discharge of hospital inpatients that would otherwise have been treated with NPWT in hospital, as a result of growing confidence in the ability of community staff to manage complex wounds using NPWT. This provision of continuity from the acute care setting to community is likely to result in a considerable reduction in the cost of wound care compared with that of keeping a patient in hospital. The average cost of one day's inpatient stay was estimated to be £288 (4).
• •Reduced use of resources for wounds where the alternative to NPWT would require high levels of resource use. For example, some wounds produce copious quantities of exudate and may need very frequent dressing changes. A reduction in dressing change frequency may lead to a reduction in both nursing time and the quantities of consumables used. Initiation of NPWT in the community might be appropriate for these wounds.
• •The use of NPWT for wounds where there is a high risk of complications, which may lead to further high‐cost interventions such as emergency hospital admission for grafting or amputation. Again, initiation of NPWT in the community may help to prevent these interventions. For example, the incidence of minor and major amputations are reduced in patients with diabetic foot ulcers treated with NPWT (9).

In the early days of NPWT, the majority of its use was in hospital rather than community care, partly because of the limitations of the technology. Traditionally, the availability of funding for the use of NPWT in community care has tended to be a decision made by each individual community provider organisation, and as a result, it has been highly variable across the UK. Some community providers may have taken a cautious approach to the funding of NPWT, and in some cases, acute trusts have continued to fund NPWT for a period post‐discharge. Continuation of NPWT allows patients to regain mobility and resume usual activities of daily living more quickly, concomitantly reducing the cost to the NHS, since earlier discharge is facilitated. In this way, hospital beds can be made available so that other patients can be treated and waiting times reduced.

The practicalities of NPWT in community care

NPWT has the capability to be an effective tool for the treatment of wounds. However, alongside its practical implementation, there are a number of supporting processes and ways of working that will enable the potential of the technology to be realised:

• 1Clear clinical pathways for decision making: when to use NPWT and for the transfer of patients from secondary to primary care.
• 2Agreed funding or budget allocation if NPWT not sourced on FP10.
• 3Guidelines on how to use NPWT.
• 4Strategies for monitoring and evaluation by tissue viability teams to optimise usage and show quality of care.
• 5Appropriate competency‐based education and training.
• 6Interaction with and support from industry.
• 7Monitoring and tracking of NPWT to manage resource use.

In particular, monitoring of the use of NPWT is potentially very valuable. It enables clinical decision makers to understand how NPWT is being used, what patient groups most benefit from it, and it also allows resource use to be tracked. For example, the duration of treatment, the number of home visits and the quantities of consumables such as dressings and canisters all can be recorded. In addition, it provides an opportunity to track outcomes and check that the objectives of treatment are being achieved. The NHS Outcomes Framework requires a focus on delivering outcomes and all services will need to have mechanisms in place that report on tangible improvements to patients (1). Perhaps most importantly, it can be used in a trust‐specific setting to identify which groups of patients will gain most benefit from NPWT.

In three community trusts in England, a method of tracking the use of NPWT has been piloted for some time. The tracking tool uses a bespoke Access database with a user‐friendly front end, allowing rapid data entry into on‐screen forms, using controls such as drop down menus and check boxes. In this way, each episode of NPWT can be tracked, and summary analyses can be undertaken to provide data reports for senior management and commissioners.

Of the three community health care providers, two serve populations in both urban and rural communities, with some outlying rural areas. The third is based in a metropolitan area where the population density is high.

In these trusts, experienced tissue viability specialist nurses oversee the use of NPWT, advising on its use and monitoring outcomes. Increasingly, however, district nurses have become more familiar with the technology and been trained in its use. In many cases, they are now able to use it routinely, and consequently tissue viability specialist nurses are able to make efficient use of their time by directing their expertise to cases where their experience is most needed.

To be able to target educational programmes and assess the economic benefits of using NPWT in the community, some of the relevant resource use data are summarised below.

METHODS

Three community trusts tracked the use of NPWT resources over the period May 2009 to September 2010. For each episode of NPWT, data on duration of treatment and the types of consumables used were collected, alongside information about wound types and whether wounds originated in the community trust or came from the acute care setting. The numbers of dressing changes and canister changes per week were recorded and used to calculate the numbers of dressings and canisters used over the duration of NPWT, for each episode.

Costs were estimated by multiplying the resource use data by standardised unit costs (Table 1). For this analysis, a rental model was assumed. In cases where NPWT pumps are purchased as capital items, the unit cost will be a function of the initial purchase price, the length of time over which the pump depreciates in value and the level of utilisation. For all dressings and canisters, Renasys™ (Smith & Nephew, Hull) unit costs were obtained from the NHS Drug Tariff, and for pump rental, the contracted rental tariff was used from the Smith & Nephew UK price list. The cost of a district nurse visit was taken from Curtis 2010 (15).

Table 1.

Unit costs

Item	Unit cost * (£)
Small dressing (foam)	19.15
Medium dressing (foam)	22.25
Large dressing (foam)	26.39
Small dressing (gauze)	16.64
Medium dressing (gauze)	20.86
Large dressing (gauze)	26.48
Small canister	18.77
Large canister	25.88
Pump rental (per month)	365.00
District nurse visit	35.50 †

^*UK Drug Tariff May 2011 (16).

^†Assumes 30 minutes contact time at £68 per hour, plus travel costs of £1·50.

RESULTS

Summary of resource use data from the three trusts

For 255 episodes of NPWT over the period May 2009 to September 2010, Table 2 shows a summary of the wound types treated. These included 190 wounds from one organisation, 57 from a second and 8 from a third. The majority of the wounds were surgical.

Table 2.

Wound types treated

Wound type	Number of episodes	Percentage of episodes (%)
Surgical	172	68.8
Amputation	23	9.2
Pressure ulcer Grade 4	20	8.0
Diabetic foot ulcer	9	3.6
Pressure ulcer Grade 3	8	3.2
Other	7	2.8
Traumatic	6	2.4
Venous leg ulcer	3	1.2
Arterial leg/foot ulcer	1	0.4
Graft site	1	0.4
Subtotal	250	100.0
Not recorded	5
Total	255

Excluding two wounds where the origin was not recorded, 85·8% of wounds originated in the acute care setting. Of these 217 wounds, 204 included data on the speciality from which the wound had originated. As shown in Figure 1, the most common speciality was general surgery (54%) with orthopaedics 16% and the vascular department 10%.

Figure 1.

Speciality (wounds originating from acute setting).

The most common NPWT pump type was the Renasys Go™ system (Smith & Nephew). For some episodes, the pump type was changed part way through the episode, and in some cases, pumps other than Renasys were used throughout. Excluding four episodes where the duration of treatment was not clear, the mean duration of NPWT was 21·4 days (median 17 days). As Figure 2 shows, most episodes of NPWT lasted for 28 days or less.

Figure 2.

Duration of NPWT.

In the majority of cases, NPWT dressings were changed three times per week (Table 3), the mean number of changes per week being 2·73. Canisters were usually changed once or twice per week (Table 3).

Table 3.

Frequency of dressing/canister change

Changes per week	Dressings Number of episodes (%)	Canisters Number of episodes (%)
1	7 (2·9)	102 (44·9)
1.5	0 (0·0)	1 (0·4)
2	52 (21·8)	100 (44·1)
2.5	1 (0·4)	0 (0·0)
3	178 (74·5)	23 (10·1)
4	1 (0·4)	1 (0·4)
Subtotal	239 (100·0)	227 (100·0)
Not recorded	16	28
Total	255	255

There are several sizes of NPWT dressing available to allow treatment of various sizes of wound. The most common dressing size used was small, as shown in Table 4. The dressing type was recorded for 179 episodes, gauze being used for 57% of these episodes and foam for 43%. Table 5 shows the duration of NPWT by type of wound.

Table 4.

Dressing sizes used

Dressing size	Number of episodes	Percentage of episodes (%)
Small	120	53·8
Medium	76	34·1
Large	27	12·1
Subtotal	223	100.0
Not recorded	32
Total	255

Table 5.

Duration of NPWT by wound type

Wound type	Mean duration of NPWT (days)	Number of episodes
Pressure ulcer Grade 4	30.3	20
Pressure ulcer Grade 3	24.5	8
Venous leg ulcer	24.0	3
Other	23.3	7
Diabetic foot ulcer	22.4	9
Surgical	21.2	170
Amputation	18.3	21
Traumatic	12.8	6
Arterial leg/foot ulcer	5.0	1
Graft site	3.0	1

Cost analysis

Costs were calculated for the 251 episodes where the duration of treatment was known. The mean total cost per episode of NPWT was £818, and a breakdown of costs is shown in Table 6. The average materials cost per episode (including pump rental) was £522 whilst the cost of nursing time was £297 per episode. Table 6 also shows the mean cost per day; the mean cost of materials per day was £24·33, whilst the nursing costs were £13·83 per day. Table 7 shows the cost per episode by type of wound.

Table 6.

Cost breakdown

Item	Mean cost per episode (£)	Mean cost per day (£)
Dressings	168	7.86
Canisters	96	4.47
Pump rental	257	12.00
Nursing visits	297	13.83
Total	818	38.16

Table 7.

Cost per episode by wound type

Wound type	Mean cost per episode (£)	Number of episodes
Pressure ulcer Grade 4	1210	20
Pressure ulcer Grade 3	801	8
Venous leg ulcer	1055	3
Other	701	7
Diabetic foot ulcer	796	9
Surgical	811	170
Amputation	734	21
Traumatic	513	6
Arterial leg/foot ulcer	264	1
Graft site	148	1

Wounds that had originated in hospital but were now being treated in the community made up the majority of those treated. For these episodes of NPWT, the mean duration was 20·4 days, and the mean cost per episode was £784 (comprising £499 materials costs and £285 nurse visit costs). The mean cost per day was £38·50 (comprising £24·50 materials costs and £14·00 nurse visit costs).

For wounds where NPWT was initiated in community, the mean duration of NPWT was 28·8 days, and the mean cost per episode was £1059 (comprising £680 materials costs and £379 nurse visit costs). The mean cost per day was £36·80 (comprising £23·62 materials costs and £13·18 nurse visit costs).

DISCUSSION

Earlier discharge from hospital

Without the provision of NPWT in the community, hospital inpatients requiring NPWT would need to stay in hospital to receive the treatment. However, once NPWT is available, continuity of care from acute to community is possible, allowing patients to be discharged on NPWT earlier than would otherwise be the case. The process for making NPWT available for patients on discharge from hospital is similar in the three trusts. Community nurses and tissue viability teams liaise with hospital staff to arrange continuity of treatment. The mean cost per day of £38·50 is a relatively small cost compared to the daily cost of hospital stay, which was recently estimated to be £288 per day (4). The mean cost of an episode of NPWT in community for patients originating in the acute setting was £784 over an average duration of 20·4 days. An equivalent period of hospital stay would incur costs of approximately £5760. Hence, by treating the patient in the community, there is an estimated cost saving to the NHS of £4814 per patient.

This approach is aligned with the NHS commitment to treating more patients in community (14). It has the additional advantages of enabling more district nurses to become familiar with the NPWT technology, thus increasing their skills, under the direction of experienced tissue viability nurses (TVNs). By treating more patients in community and discharging earlier with NPWT, hospital beds can be freed up. On average by discharging from hospital on NPWT, each patient freed up 20·4 days, which would otherwise have been spent in hospital on NPWT.

For some trusts where NPWT pumps have been purchased, demand is high because the benefits of earlier discharge on NPWT have been recognised. In this case, additional rental contracts are being set up to allow for peaks in demand.

The initiation of NPWT in community for high‐resource wounds

Initiation of NPWT in community in the three trusts is overseen by tissue viability staff, liaising with community nurses. NPWT has traditionally been initiated in hospital, and this continues to be the case for the majority of wounds. However, there is a sub‐population of wounds for which NPWT may provide advantages by being initiated in community, for example, if:

• •resource use might otherwise be very high (e.g. frequent nursing visits)
• •the use of NPWT might prevent further complications which could result in admission to hospital.

NPWT may have clinical benefits over advanced wound dressings for certain wounds and could be successful if effectively targeted for a managed and controlled period. In addition, the cost of treatment with NPWT may turn out to be lower than advanced wound dressings, if the use of resources is very high. Unit costs of some advanced wound care products may in themselves be relatively high. For the three trusts described in this study, where NPWT was initiated in community, the mean duration of NPWT was 28·8 days, and the mean cost per episode was £1059. Often, wounds in this category might otherwise require multiple primary dressings covered with a secondary dressing, in many cases changed on a daily basis. For example, the use of four primary dressings (Aquacel™ Ribbon 1 × 45 cm, Convatec, at £1·76 per unit) with a foam dressing (Allevyn Adhesive™ 17·5 × 17·5 cm, Smith & Nephew at £5·07 per unit) changed daily would incur a cost of £47·61 per day (including the cost of nursing time at £35·50 per day), or £1333 over the 28‐day period. In addition, there is considerable inconvenience to the patient of daily dressing changes and potential leakage if exudate is not controlled. Changing dressings less frequently should reduce both exposure to external contaminants and disruption to the wound healing process.

Wounds at high risk of complications

Treatment of wounds at high risk of complications such as diabetic foot ulcers with NPWT may incur a relatively small cost compared with the cost incurred as a consequence of other interventions such as debridement and offloading.

For the three diabetic foot ulcers included in the data described above, the mean duration of NPWT was 22·4 days, at a mean cost per episode of £796. This represents less than the cost of 3 days' hospital stay. The consequences of complications in diabetic foot ulcers can be severe, both in terms of the human cost for the patient and in terms of the economic cost to the NHS. For example, the national average cost of an inpatient episode for an amputation with major complications is £12131, with 31 days length of stay. Foot procedures for diabetes or arterial disease are estimated to cost £4803, with 13 days length of stay (NHS National Reference Costs (17)). Evidence suggests that diabetic foot ulcers treated with NPWT are less likely to require secondary amputation (9) and are more likely to heal in a timely fashion (11). Additionally, by healing the diabetic foot ulcer earlier, long‐term use of antibiotics may be avoided.

Management of NPWT in community health care

The data show that in the three trusts, NPWT was used over a relatively short and controlled window of time for each episode of care. This targeted and managed approach to treatment is guided by clinical decision making by experienced nursing staff. In this way, wound care can be optimised by directing resources where they will provide the greatest clinical benefit. Additionally, there are potential cost savings for some provider organisations where NPWT has been commissioned through a block contract. Even though NPWT is a potentially valuable technology, there may be some patients for whom it may not be appropriate or practicable in community care. All patients should be assessed on an individual basis and have equality impact and risk assessments to ensure every patient has the opportunity to benefit from NPWT.

As the experience of using NPWT and the data both accumulate, the efficiency of the process should increase. The ability to track resource use is therefore a useful adjunct to clinical knowledge and experience, to aid decision making and optimise clinical and economic benefits. This is particularly useful where trusts have an agreed budget for the management of wounds using NPWT. For example, one trust has agreed with the commissioners an average number of days' use of NPWT per episode of care. Tracking enables this trust to monitor resources against this allocation.

Negative pressure has evolved from large devices using foam, which were relatively heavy and ideal for the acute setting but difficult to use in the community, to smaller, more portable devices, which can allow a smoother transition from hospital to community. The use of gauze as a filler is also a key evolutionary step in the delivery of negative pressure. As with most technologies, negative pressure therapy devices have now become even smaller with the advent of personal single patient use devices, which are not much bigger than a mobile phone.

Some of these devices also come with a dressing and can be used with a filler to deliver negative pressure to a variety of wound types. There are many benefits to this simpler form of negative pressure, for example, reduced need for staff training and easier access because of the off‐the‐shelf ordering process. Such devices and dressings are likely to have a significant impact on the community, reducing the fear of having an electrical device in the home and allowing the patient a greater degree of mobility. The true impact of these improvements in technology are difficult to predict, however, it would appear that negative pressure as a therapy is not standing still and with each development there is the potential for patients and clinicians to benefit.

CONCLUSIONS

There is a compelling case to fund NPWT in community care, to facilitate earlier discharge of inpatients who would otherwise have been treated with NPWT in hospital. Next, NPWT has the potential to reduce the use of resources for wounds where the alternative would require high levels of resource use. For wounds where there is a high risk of complications (such as diabetic foot ulcers), which may lead to further high‐cost interventions, the cost of NPWT may be relatively small compared with other interventions such as debridement and offloading.

Targeted use of NPWT, managed by experienced tissue viability staff, is likely to result in more efficient use of resources. However, it is essential to support NPWT through training and education and monitor its use in day‐to‐day clinical practice.

Limitations

It should be noted that the conclusions drawn in this article are subject to the limitation that the number of episodes of care is relatively small. In particular, the majority of wounds were surgical in origin, and consequently, wounds other than surgical represent a small proportion of the total.