Michael Clark

Analysis of Skin Wound Images Using Digital Color Image Processing: A Preliminary Communication

This article presents the use of digital image processing using hue, saturation, and intensity measurements as a technique for the color analysis of chronic wounds on the skin. An adaptive spline technique was used to segment the wound boundary in the images of venous leg ulcers. This technique was further used to approximate the position of venous leg ulcers. The amount of slough within the wound site was quantified using the software developed and was compared with a grading system based on visual inspection by an experienced clinician, and the results were compared by deriving Kappa (K) statistic. There was moderate agreement over all grades between the computer and clinician. At lower grades 1 and 2, there was excellent agreement. The results from this preliminary study suggest that this analytical technique has the potential to image process chronic skin wounds.

Improving the accuracy of pressure ulcer risk calculators: some preliminary evidence

This study presents data from a prospective cohort study of 213 in-patient admissions of people over 65. Logit analysis was used to investigate the relative contribution of a range of risk factors to the risk of pressure ulcer occurrence, as a basis for development of improved risk assessment tools. It was found that for this population, a model containing the Waterlow risk factors appetite, continence, skin condition and age, plus diagnosis, performed better than one based on the complete set of Waterlow factors. Gender was not significant. A diagnosis of cancer was positively associated with pressure ulcer occurrence but presence of Parkinsons disease had the opposite effect.

Barriers to the implementation of clinical guidelines

Clinical guidelines in wound care have recently been formulated at the national and international level, reflecting a shift from locally derived guidelines common during the 1990s. There remains considerable uncertainty regarding the extent of implementation and monitoring of these new guidelines. This paper presents the results of a survey of members of the Tissue Viability Society that sought their views upon the guidelines in place within their workplace--how were these guidelines developed, was the impact of guidelines monitored and how and finally what barriers limited their full implementation. Of the 1500 members, 476 returned completed questionnaires (34.0% response rate). Most (n = 422, 88.4%) worked within environments that implemented clinical guidelines in some aspect of wound care, with guidance upon pressure ulcer prevention being most commonly reported (n = 351). The use of national guidelines (either in their original format or locally modified to reflect local circumstances) was relatively common--reported by 307 of the 476 respondents. Few reported that guidelines were fully implemented (n = 77; 18.3%) with lack of resources, lack of awareness of the content of the guidelines and, when aware, lack of acceptance of their recommendations being the most commonly cited reasons for the failure to implement. However, it should be noted that only 34.0% of the surveyed population responded--this may question how far the results can be considered to reflect the current status of guideline implementation in the UK given the unreported views of 66% of all those surveyed.

REMOVING THE 'ESTIMATES AND GUESSES' FROM PRACTICE -EVIDENCE BASED TISSUE VIABILITY.

The development of evidence based tissue viability is reviewed using the prevention and management of pressure sores as a specific example. Although data is limited, pressure sores may be more common at the end of the 1990s than they were fifteen years ago, despite changes in clinical practice. If evidence based tissue viability is to grow and mature, then two key obstacles must be overcome; changes in patient populations must be reflected within prevalence or incidence data (case-mix adjustment) so allowing interpretation of longitudinal changes in the occurrence of sores. Secondly, the efficacy and effectiveness of interventions such as pressure-redistributing beds and mattresses must be identified through rigorous and appropriate methodologies. Only through such steps can clinical skill be blended with research evidence to fully realise evidence based practice.

The Effect of A Dynamic Pressure-Redistributing Bed Support Surface upon Systemic Lymph Flow and Composition

INTRODUCTIONnIt has been postulated that lymphatic insufficiency may have a key role in pressure ulcer development. Our hypothesis is that the particular dynamic action of the Airwave mattress directly improves lymphatic circulation compared to conventional hospital mattresses.nnnMETHODSnSeven anesthetized sheep (40-48 kg) prepared with chronic prefemoral lymph fistulas and vascular catheters were first placed on a standard hospital mattress. Following 30 minutes of equilibration, a 2 hr control period was started measuring lymph flow and vascular pressures. The standard mattress was then exchanged for an active Airwave mattress (Pegasus Egerton, Ltd.) and after 30 minutes of equilibration monitored as above. After 2.5 hr, the support surface was then switched back to the standard mattress and monitored as before. Data are mean +/- sem.nnnRESULTSnInitially, on the standard mattress, lymph flow was 1.0 +/- 0.2 ml/30 min and increased significantly more than 3 fold on the Aireave mattress to 3.7 +/- 0.7 ml/30 min. Upon return to the standard mattress, lymph flow decreased to 1.2 +/- 0.2 ml/30 min. Hemodynamic variables and arterial blood gases were constant. Lymphatic protein transport increased significantly from 1.3 +/- 0.3 micrograms/min to 4.3 +/- 1.0 micrograms/min when placed on the test mattress and decreased when returned to the standard mattress to 1.3 +/- 0.2 micrograms/min. Similar rates of lymph flow were seen upon a variant of the Airwave mattress (Cairwave Therapy System).nnnCONCLUSIONSnResults support the hypothesis that the Airwaves action increased the lymph flow compared to a standard hospital mattress. The dynamic cycle may act to aid the pumping action of lymphatics by reducing pressure which would otherwise collapse and compress lymphatics leading to local edema and tissue swelling.

Re‐positioning for pressure ulcer prevention

This is the protocol for a review and there is no abstract. The objectives are as follows: n nTo conduct a systematic review of research evidence to answer the following questions: n n nDoes manual repositioning of patients reduce the incidence of pressure ulcers compared with no repositioning with or without specialised support surface provision n n nDo schedules for manual repositioning reduce pressure ulcer incidence compared with repositioning on an ad hoc basis? n n nAre 2 hourly changes of position more effective in reducing pressure ulcer incidence than other frequencies of position change? n n nAre particular patient positions associated with lower pressure ulcer incidence than others?

The Development, Dissemination, and Use of Pressure Ulcer Guidelines

Clinical guidelines have been defined as “systematically developed statement(s) to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances.” In this definition the use of “assist” clearly indicates that a successful guideline does not seek to compel practitioners to practice in a rigid, inflexible manner but rather that evidence-based or evidence-linked recommendations are offered to help reduce inequities in healthcare provision. While clinical guidelines are a relatively recent phenomenon, there are now a wide range of national and international clinical guidelines that address pressure ulcer prevention and/or management beginning with the consensus guidelines developed in the Netherlands in 1985, through the US Agency for Health Care Policy and Research guidance issued in the early 1990s (on prevention and treatment) to European guidelines developed by the European Pressure Ulcer Advisory Panel (EPUAP). Recently the wheel has turned full circle with the development of new national guidelines in both the Netherlands and the UK under the respective auspices of the Dutch Institute for Healthcare Improvement (CBO), and the National Institute for Clinical Excellence (NICE). The CBO is an independent, not-for-profit organization advising on clinical guideline development across the whole spectrum of healthcare, while NICE was established as a Special Health Authority within England and Wales in April 1999. Working within the UK National Health Service, NICE seeks to deliver “authoritative, robust and reliable guidance” (www.nice.org.uk) regarding what constitutes best practice, with this information available to all consumers, be they patients, the public, or the health professionals. The wealth of pressure ulcer guidelines has been developed using a variety of methods that seek to synthesize the available scientific and clinical knowledge available during each guideline’s development. Early national guidelines, for example the Dutch guidelines of 1985 (prevention) and 1986 (treatment), were developed using informal consensus techniques. Later guidelines such as those of the US Agency for Health Care Policy and Research (AHCPR) were based on formal consensus techniques, with more recent guidelines seeking to be based solely upon the best practices of evidence-based medicine. This chapter discusses the evolution of pressure ulcer guideline development using the new Dutch guidelines as examples of evidence-based national guidelines. Beyond guideline evolution aspects of their dissemination, implementation, and appraisal will also be considered.

Innovation in Pressure Ulcer Prevention and Treatment

‘Innovation’ is one of the most over used words in recent years, almost every advertisement appears to promote products and services not simply as being ‘new’ but more importantly as being ‘innovative’. In this chapter we define innovation to involve new activities (be these products, services or systems for delivering care) that create value (improved health both for individual patients and for our wider society). The chapter focuses upon several aspects of pressure ulcer prevention and treatment that have benefited, or would benefit from recent innovation including; n n nInnovation in guideline development. n n nNew perspectives on pressure ulcer aetiology. n n nInnovation in public health systems. n n nInnovation in clinical services. n n nInnovation in emerging therapies, and n n nNext steps for new innovations in pressure area care.

The Stop Pressure Ulcer Day and Other Initiatives by EPUAP

Pressure ulcers are not only a cost-driver for health care systems around the world, but can also result in significant morbidity and even death. The prevalence of pressure ulcers ranges between 8.8 and 29.9% in nursing homes and between 7.3 and 23% in hospitals throughout Europe and North America. These wounds are associated with major problems for patients, their relatives and for care-givers. Reductions in quality of life including pain, changed body image, increased immobility, discomfort, loss of independence and self-control have been reported. The general consensus is that most pressure ulcers could have been prevented. Despite the potential for health gains and reduced costs through effective pressure ulcer prevention there is still an overall lack of awareness of this condition among policy makers and the public. One example of this lack of awareness lies in the continued general use of ‘bedsore’ to describe these wounds rather than ‘pressure ulcer’. This chapter sets out how the EPUAP has contributed to raising the awareness of pressure ulcers throughout Europe.

Innovation in Pressure Ulcer Prevention and Management

For many practitioners achieving successful pressure ulcer prevention and management has long been regarded as a straightforward task albeit one that is often not achieved. This view was succinctly described in the first paper presented at the first UK pressure ulcer conference back in 1975 when Roaf commented that “we know how to avoid bed sores and tissue necrosis—maintain the circulation, avoid long continued pressure, abrasions, extremes of heat and cold, maintain a favourable micro-climate, avoid irritating fluids and infection. The problem is the logistics of this programme.” So now, thirty years after this seminal meeting on pressure ulcers, does such a statement still hold true and have we really achieved significant innovations in our research and practice which have helped resolve the logistical challenges in service delivery? There are four key dimensions where pressure ulcer innovations might be encountered—in clinical practice, research, the organization and logistics of service delivery, and finally in society’s views on the significance of pressure ulceration. Each dimension clearly overlaps with its neighbors but will be treated separately in this chapter both to tease out advances and to identify the challenges that remain.