Diabetic foot disease is a severe complication involving deep tissue lesions, and it is associated with current or previously diagnosed diabetes. Among the complications that may manifest are peripheral neuropathy, peripheral artery disease, infection, ulcer(s), neuro‑osteoarthropathy, gangrene and amputation. Foot ulceration is among the most serious complications of diabetes, which can lead to a reduced quality of life and incur financial costs for the person affected. Moreover, it places a considerable burden not only on the person's family, but also on health professionals and services, as well as society in general (Zhang et al, 2017; Fu et al, 2019; International Working Group on the Diabetic Foot (IWGDF), 2023). According to the IWGDF:
‘The vast majority of persons with a diabetes-related foot ulcer will have neuropathy. Peripheral artery disease (PAD), generally caused by atherosclerosis, is present in up to 50% of these patients and is an important risk factor for impaired wound healing, gangrene and lower-extremity amputation. A small percentage of foot ulcers in patients with severe PAD are purely ischaemic … the majority of foot ulcers, however, are either purely neuropathic or neuro-ischaemic ….’
Diabetic foot ulcers (DFUs) have a major impact on patients’ quality of life – mainly due to pain, mobility problems, and having to limit social activities and relationships– as well as on health system resources (Prompers et al, 2008; Monteiro‑Soares et al, 2021). As the disease progresses, the care of the individuals affected incurs major economic costs. There is therefore a need to identify costreduction strategies, applying more focused research and more robust methods to estimate costs (Graz et al, 2018;Tchero et al, 2018). The management of DFUs remains a challenge, with continued uncertainty regarding optimal approaches to wound healing (Vas et al, 2020).
Worldwide, DFUs are among the most frequent causes of amputation, hospitalisation and disability (Jeffcoate et al, 2018; Lazzarini et al, 2020). They are estimated as preceding about 80% of amputations (Graz et al, 2018), with, globally, a lower limb amputation potentially occurring every 30 seconds due to diabetes (Boulton et al, 2005; Fu et al, 2019). There are two levels of amputations: major amputation above the ankle and minor amputation below the ankle (Wrobel et al, 2001).
‘Diabetic foot attack’, a relatively new term, has been used to describe an acute, severe presentation that places the preservation of the affected limb at risk and, in some cases, it can even pose a threat to the patient's life (Vas et al, 2018; Carro et al, 2020). The term has arisen due to a need to identify patients requiring urgent intervention, which invokes the same sense of urgency and severity as that required to manage heart attack and stroke, reinforcing the concept that ‘time is tissue’ (Vas et al, 2018; Carro et al, 2020).
Three groups of complications have been identified as requiring urgent appropriate intervention (Vas et al, 2018; Carro et al, 2020):
- Infected ‘diabetic foot attack’, requiring rapid debridement of devitalised tissue, drainage of collections and antibiotic treatment
- Ischaemic ‘diabetic foot attack’ involving progressive ischemia, which requires urgent revascularisation
- Charcot neuro‑arthropathy in the acute phase.
In Andalusia, Spain's most populated region, the public Andalusia Health Service (Servicio Andaluz de Salud) has established an integral diabetic foot pathway (Martínez Brocca, 2018), which outlines a number of indicators that facilitate the early identification of severe diabetic foot disease. This promotes effective management using a multidisciplinary approach, thereby helping to reduce lower limb amputations in people with diabetes. Analysis of health outcomes related to diabetes for the Andalusia's Ministry of Health (Consejería de Salud) (Martínez Brocca and Mayoral Sánchez, 2016) has identified this as one of the main areas for improvement in the management of diabetic foot disease in the region.
In 2015, in response to specific patient population needs, the role of the advanced practice nurse (APN) in complex chronic wounds was piloted in four of the 36 districts of Andalusia, including Poniente de Almería Health District (Distrito Sanitario Poniente de Almería); it has subsequently been extended to all 36 districts. Following the initial introduction of the role, the authors undertook a study in the four pilot districts to determine the following:
- The characteristics of patients referred to the specialist APN in complex chronic wounds who, in addition to diabetes, have neuropathic and neuro‑ischaemic lesions
- The effects on practice of implementing a training strategy, to facilitate modification of individual patient care plans and to ensure better continuity of care. The course is aimed at nurses working with patients with diabetic foot disease who attend primary care centres and those living in nursing homes
- Whether, following the introduction of training, there were positive changes in the follow‑up and evaluation of diabetic foot in patients with both neuropathic ulcers and neuro‑ischaemic ulcers referred to the APN.
Method
This was a retrospective descriptive study of patients with diabetic foot disease referred to the APN in complex chronic wounds. Patients had neuropathic and neuro‑ischaemic ulcers, as identified by the protocols and algorithms set out in Andalusia's care strategy. The data of all patients referred to the APN from the introduction of the role in 2015 were analysed over a period of 6.5 years. Over this period one nurse was employed in the role of APN in complex chronic wounds in the four pilot areas, who followed patients through until either discharge or death.
The study population comprised all patients with diabetic foot ulcers referred to the APN by nurses and doctors from the various specialist clinical hubs within the district.
Inclusion criteria
All patients who met the previously established criteria for referral to the APN, namely:
- Individuals with particularly hard‑to‑heal ulcers – that is, wounds that have had adequate management of bacterial load for at least 2–4 weeks – but whose wounds had either:
- Had a score of 25‑26 on the RESVECH scale for a consecutive 6 weeks (see Box 1)
- Showed no clear signs of improvement after 12 weeks of treatment
- Any other situation that necessitates a consultation with the APN, for example if it is considered that the patient cannot be assessed on an outpatient basis.
Box 1.
RESVECH 2.0 assessment scale for hard-to-heal wounds
| Dimension | Score range |
|---|---|
| Wound area | 0–6 |
| Depth | 0–4 |
| Edges | 0–4 |
| Tissue type | 0–4 |
| Exudate | 0–3 |
| Infection/inflammation | 0–14 |
| Total score: 0 (healed injury) to 35 (worst injury) |
Source: Restrepo Medrano, 2010
Exclusion criteria
Patients who were transferred to another health district within the 6.5‑year period of the study, which meant that follow‑up was not possible.
Sampling and sample size
Non‑random convenience sampling was used to select patients for inclusion in the study, with the data collected by the APN between 1 June 2015 and 31 December 2021 reviewed retrospectively as part of the study. All patients who met the inclusion criteria for chronic wound type were included.
Study variables
The specialist APN developed a training course,‘Nursing care in the management of diabetic foot disease’, which was accredited by the Andalusia Health Service. The course was run before the start of the period under review for the study, and was attended by primary care nurses, nursing home nurses, and by hospital nurses. The course covered the following points:
- How to examine the diabetic foot
- Frequency of examinations
- Most frequently occurring types of DFUs
- How to prevent and manage the ulcers in the initial phases
- The process of referring patients to the specialist APN.
The training included theoretical and practical components. The 7‑hour course took place in June 2019 and was run seven times (a total of 49 hours), with 168 nurses attending.
To evaluate whether the training had resulted in positive changes in the performance of the professionals (and helped improve individual patient care plans and continuity of care), participants completed a pre‑ and post‑training questionnaire.
These were aimed at assessing the nurses’ new knowledge, as well as their understanding of referral protocols in the case of patients with complex wounds and poor healing times, and the correct management of bacterial load for at least 2 to 4 weeks.
In addition, and in order to meet the third objective, the following variables were identified for analysis:
- Percentages of patients referred to the specialist APN with neuropathic and neuro‑ischaemic ulcers
- Annual healing rates and cumulative rates over the 6.5 years
- Proportion of patients who were referred by the APN to hospital specialists, with the number of these ulcers per year
- Proportion of patients with DFUs who underwent some type of surgical intervention, such as minor and major amputations and numbers per year
- Proportion of affected patients who died per year over the course of the period analysed.
Data sources
The data were collected and retrospectively analysed by the specialist APN using the data collection tool developed for this purpose (the Diraya wound registry). The patient records were subsequently cross‑referenced to ensure that there were no errors in the data. The data were then presented, analysed and verified by the management of Distrito Sanitario Poniente de Almería.
In addition, data from each patient's record, referral reports to hospital specialists, admissions and the information entered on Andalusia's electronic registry system (Diraya) skin assessment tool were used to calculate and analyse the data collected over the 6.5 years.
From the information available from the wound registry, the specialist APN selected variables that would support the objectives of this project: for example, time to healing, duration of non‑healing ulcers, risk of deterioration without amputation and time to death.
Data analysis
A descriptive sequential analysis was performed, calculating frequency measures and percentages for qualitative variables; means and standard deviations were calculated for quantitative variables. The analysis identified normal distributions, medians and ranges for each variable. Excel PivotTables were used for analysis, in conjunction with the statistical software package SPSS v21.0.
Ethical considerations
This study was commissioned by the management of Distrito Sanitario Poniente de Almería as part of quality improvement initiative. It was part of a larger project to evaluate the clinical work of the specialist APN in Andalusia, which aims to measure the impact of the APN on the outcomes of patients with wounds of various aetiologies: pressure ulcers, lower limb extremity injuries, diabetic foot injuries, as well as costeffectiveness and improved management outcomes.
The study received approval from the Research Ethics Committee of Centro Almería in 2016 (Protocol code 48/2016) in accordance with the ethical principles in research studies with human beings, standards of good clinical practice, and the order of the Ministry of Health and Consumption 256/2007. The protocol also complied with the ethical principles of the 2013 Declaration of Helsinki and other international codes.
Results
Over the study period, a total of 103 patients with diabetes with ulcers of both neuropathic and neuro‑ischaemic origin were referred to the specialist APN for assessment, follow‑up, and subsequent review of their DFUs.
Demographics
Of the 103 referrals, 78 were men (76%) and 25 (24%) were women, and the mean age was 69.44 years (SD 5.17) (Figure 1).
There were 50 patients (48.54%) with a DFU of neuropathic aetiology and 53 (51.45%) with a DFU of neuro‑ischaemic origin (Figure 2). Diabetic foot lesions were found to be more common in men, with a ratio of 3:1 men to women, which was more apparent between the ages of 65 and 80 years. There was no predominance of DFU type across each year.
Healing rates
More than half of the patients referred to the APN (61/103; 59%) achieved complete healing of their ulcers (RESVECH score 0); 24/63 (39%) DFUs were of neuro‑ischaemic origin and 37/103 (61%) of neuropathic origin. In addition, the authors wanted to establish the time to healing for the ulcers of patients referred to the specialist APN and to evaluate ulcer complexity and difficulty in healing.
Average healing time for DFUs of both neuropathic and neuro‑ischaemic aetiology was 13.1 months (CI 95% 5,0‑20,2) (time to healing of more than 1 year) (Figure 3). It is worth examining the data for the year 2020: it is evident that the COVID‑19 pandemic affected follow‑up routines for these chronically ill patients and the care of these wounds in the primary care system, with the result that time to healing increased significantly than would have been expected based on experience.
Complications and surgery
As a result of complications, comorbidities and triggering factors a number of patients received urgent referrals to the Hospital Universitario Poniente to undergo surgery, in many cases requiring minor or major amputations. Over the study period, the specialist APN referred 24 patients (Table 1) to the hospital immediately after initial diagnosis. Of these early referrals made by the APN to the hospital, 16/24 (67%) had DFUs of a neuro‑ischaemic aetiology and 8 (33%) of neuropathic origin. The established protocols were used to assess these patients against the data in the Diraya registry, which identified that 100% of the 24 referrals were appropriate, and had resulted in hospital admission for the majority of patients.
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | Cumulative total | |
|---|---|---|---|---|---|---|---|
| Neuro-ischaemic ulcers | 2 | 3 | 4 | 1 | 3 | 3 | 16 |
| Neuropathic ulcers | 0 | 1 | 0 | 3 | 1 | 3 | 8 |
| Total | 2 | 4 | 4 | 4 | 4 | 6 | 24 |
Of the 16 patients referred with neuro‑ischaemic ulcers, 9/16 (56%) underwent minor amputation (below the knee) following admission and 2/16 (13%) a major amputation (above the knee) following admission. Of the 8 patients referred who had neuropathic ulcers, 5 (63%) underwent minor amputation following admission.
The 9 patients with neuro‑ischaemic ulcers referred by the APN to hospital who underwent major amputation equate to 9% of the total number of referrals (n=103) to the APN. Major amputations occurred only in patients referred to Hospital Universitario Poniente by the APN as urgent cases.
A breakdown of the figures shows that total numbers of major and minor amputations (n=50) (Figure 4 and Figure 5) performed with reference to DFU type were as follows:
Total, minor and major number of amputations over the study period
Number of amputations by ulcer type (of 50 total amputations)
- 32 of 50 (64%) total amputations occurred in patients with neuro‑ischaemic ulcers (Figure 5), accounting for 31% of referrals with both types of DFU (32/103) to the specialist APN
- 18 of 50 (36%) total amputations occurred in patients with neuropathic ulcers (Figure 5), accounting for 17% (18/103) of total referrals to the APN
- 32 of 53 (60%) patients with neuro‑ischaemic lesions underwent amputation and 18 of 50 (36%) (Figure 5) patients with neuropathic ulcers underwent amputation, accounting for 17% (18/103) of total referrals to the APN. The number of deaths per year from initial DFU diagnosis and the cumulative totals over the 6.5 years of the study are presented in Table 2. The data show that 36% of patients died, with half of deaths occurring in the same year as the patient was diagnosed with a DFU, regardless of aetiology. Table 2 shows that, for both 2020 and 2021, patients died in the year of diagnosis or the following year.
| Deaths | Year 1* | Year 2 | Year 3 | Year 4 | Year 5 | Year 6† | Cumulative total |
|---|---|---|---|---|---|---|---|
| 2016 | 1 | 5 | 1 | 2 | 0 | 1 | 10 |
| 2017 | 3 | 1 | 1 | 5 | |||
| 2018 | 3 | 2 | 1 | 6 | |||
| 2019 | 4 | 1 | 1 | 1 | 7 | ||
| 2020 | 3 | 1 | 4 | ||||
| 2021 | 5 | 5 | |||||
| Total (%) | 19 (51) | 10 (27) | 4 (11) | 3 8 | 0 (0) | 1 (3) | 37 (100) |
Incomplete year, 6 months’ data reviewed
As mentioned above it is necessary to take into account the COVID‑19 pandemic, which disrupted the normal course of patient treatment. In the authors’ opinion, the restrictions in place and consequent difficulties in contacting patients throughout the pandemic prevented early identification of those at high risk of developing DFUs, and timely treatment. This led to late diagnoses and an ensuing increase in amputations during 2020 and 2021 due to infections and serious complications, with resulting patient deaths.
Discussion
This article has provided insights into the diagnosis, treatment and outcomes for patients with diabetes over a period of 6.5 years in Poniente de Almería Health District. It includes an overview of the role played by the specialist APN in managing and following up patients with neuropathic and/or neuro‑ischaemic wounds referred by other health professionals, and the number of patients then referred on as urgent cases by the APN for hospital treatment. Analysis of the APN role and the patient outcomes reviewed intend to facilitate improvement of the care journey for the patient, and the strategies implemented by Distrito Sanitario Poniente de Almería and the Andalusia Health Service more widely, in particular by undertaking more thorough and more frequent risk assessments to ensure early identification of possible foot injuries and implementation of earlier, more comprehensive preventive measures.
With reference to the training provided to nurses who attended the 7‑hour course, which was run seven times, the authors would like to highlight the emphasis placed on early diagnosis of DFUs. This was considered essential in order to ensure prompt action on the cause and avoid prolonged time to healing. In addition, triggering factors, such as hyperglycaemia, neuropathy, smoking and trauma, had to be taken into account along with local barriers. These included:
- Difficulties in accessing specialist foot health care
- Lack of knowledge about prevention and treatment
- High costs
- Difficulties in accessing appropriate therapeutic shoes and insoles
- Lack of adequate patient education and information.
The training course was attended by a total of 168 nurses and the study identified improvement in knowledge following participation. This was identified by the administration of a pre‑ and a post‑course knowledge test, with a comparison of the test scores showing that nurses’ level of knowledge had increased. Audits were subsequently carried out to assess nurses’ correct use of products: these identified a decrease in the use of inappropriate or incorrect products by an average of more than 10% across all participants.
It is clear that onward referral to hospital care is one of the key functions of the specialist APN, a role that encompasses the co‑ordination of urgent and effective action as quickly as possible, to ensure that patients receive prompt treatment. This may include referral to secondary care, resulting in hospital admission, which may include undergoing surgery the same day. The actions taken will depend on the characteristics and complexity of each patient.
It is important to highlight the following: three out of four patients referred to the specialist APN were men and that the average age for all patients was 69 years. Furthermore, it should be noted that, along with poor general health, DFUs not only affect quality of life by limiting mobility and causing pain and discomfort, but they also reduce life expectancy. They also have considerable economic consequences for patients, their families, and the healthcare system and society as a whole (Fu et al, 2019; Mairghani et al, 2019; Crawford et al, 2020).
The findings for the numbers of patients with neuropathic or neuro‑ischaemic ulcers referred to the specialist APN are similar to those reported previously (van Netten et al, 2016).
The findings of the current study highlight several key points that primary care nurses should consider when managing patients with DFUs. First, it is vital to identify a patient's risk factors by carrying out a comprehensive assessment. Second, it is vital to diagnose the aetiological origin of the ulcer as early as possible. Knowledge of the risk factors is crucial for developing protocols for early diagnosis, management, treatment of infection, and for prevention of amputation.
Timely recognition of DFU presentations is essential to initiate appropriate treatment and improve patient outcomes, with time a crucial factor: ‘time is tissue’ (Vas et al, 2018; Carro et al, 2020; Sen et al, 2019; Lin et al, 2020; Peters et al, 2016).
According to current evidence from systematic reviews, meta‑analyses and clinical practice guidelines on the training of health professionals in preventive measures, a number of key elements should be considered to determine a patient's risk of DFUs, specifically:
- Identification of the foot at risk
- Regular inspection and examination of the foot
- Education of the patient, family and caregivers
- Routine use of appropriate footwear
- Foot temperature: inflammation can be an indicator of the risk of ulceration
- Undertaking debridement, in collaboration with the multidisciplinary team (Crawford et al, 2020; Schaper et al, 2020; Ena et al, 2021;Vas et al, 2020).
Even with the availability of guidelines (IWGDF, 2023) and the findings of systematic reviews (Zhang et al, 2017; Fu et al, 2019; Monteiro‑Suarez et al, 2021), major challenges remain in preventing DFUs. The IWGDF guidelines (2023) make a number of recommendations – the use of therapeutic footwear (shoes, insoles, orthoses), debridement, implementation of a foot self‑care strategy for patients – these approaches are essential for reducing both the prevalence and incidence of DFUs. It is important that these measures are more widely promoted in both primary care and hospital settings.
The high number of amputations linked to DFUs, and the number of deaths in this patient group found in this study, are consistent with the findings of previous work (Moulik et al, 2003; Andrews et al, 2015; Narres et al, 2017;Vas et al, 2018). These studies reported outcomes that compare negatively with outcomes for many common cancers and heart disease.
Studies generally report data on mean survival and mortality at 5 years but they do not usually record the data for the total percentage of patients who die in the year of diagnosis, and each year subsequently. It is worth noting that the percentages of deaths at 5 years published in other studies are similar to those found in this study, with the highest percentage of amputations occurring among patients with neuro‑ischaemic ulcers compared with those with neuropathic ulcers (Moulik et al, 2003;Vas et al, 2018). Similarly, the findings of the study reported in this article are similar to those for developed countries published in the Atlas report on Diabetes Foot-Related Complications (International Diabetes Federation, 2022).
The findings reported in this article indicate an urgent need to implement a series of practical measures, underpinned by the health policies of the Andalusia Health Service, with the collaboration of primary care and hospital managements. It is vital to emphasise that following the same strategy as currently and failing to change the approach to managing DFUs will not lead to improving outcomes, no matter how much professionals at an individual level strive to do so.
Conclusion
The characteristics of a typical patient with DFUs referred to the specialist APN was that of a man aged 69 years. This knowledge allows for better understanding of the type of training health professionals need, as well as the preventive measures to be adopted, to help identify and target patients who require healthcare input.
The findings show that patients with neuro‑ischaemic ulcers have a higher risk of amputation and a higher mortality rate than those with neuropathic ulcers. Time to healing and improvement for these types of ulcers was poor, with the proportion of amputations and deaths remaining high. From the data reviewed, it is clear that, once a DFU has been diagnosed, it is difficult to prevent amputation and death.
The strategy implemented in Distrito Sanitario Poniente de Almería, which included the introduction of the specialist APN role, resulted in only a slight improvement in outcomes. The authors are therefore considering the development and implementation of a rapid, agile and practical clinical pathway between primary care and secondary care, so that all patients who have been identified as having a foot at risk of developing DFU will promptly receive appropriate preventive and health promotion measures. Co‑ordination between primary and secondary care is key to improving continuity of care, with the specialist APN playing a vital clinical role.
It is also imperative to provide education programmes for nurses working with populations at risk of DFUs, to ensure that they are able to recognise the risk factors and have an understanding of when there is a need for referral to specialist nursing or hospital services.
Key Points
- Early diagnosis of diabetic foot ulcers (DFUs) is essential to ensure prompt action and avoid prolonged healing times, highlighting the need for specialist care and co-ordination with hospital services
- Patients with neuro-ischaemic ulcers have a higher risk of amputation and mortality compared to those with neuropathic ulcers, highlighting the importance of personalised interventions and close monitoring
- The implementation of practical measures and collaborative care between primary care and hospital services is essential for improving outcomes for this patient group
- Educational programmes for nurses are vital to enable them to recognise risk factors, facilitate early referral and provide appropriate care to patients at risk of developing DFUs
CPD reflective questions
- How can healthcare systems improve co-ordination to enhance the treatment of diabetic foot ulcers and reduce the risk of amputations and mortality?
- What role can advanced practice nurses play in the early detection, treatment and prevention of diabetic foot ulcers?
- How can patient education and self-care strategies be improved to empower people with diabetes to better manage their foot health and prevent complications such as ulcers and amputations?