Clinical Effectiveness of a Larval Therapy Dressing with a Standard Debridement Technique Using a Hydrogel to Debridement of Leg Ulcers - Case Study Example

Larval Therapy, Document Review Aims and Purpose. The purpose of this document is stated as an investigation of the use of larval application, sometimes known as using maggots, to heal certain wounds in order to bring about the successful debridement of necrotic tissue. Although the use of this method is very long established, its efficacy remains a topic of debate and therefore should be investigated. The authors define their aims as :- This study aims to compare the clinical effectiveness of a larval therapy dressing (BioFOAM, BioMonde Ltd, Bridgend, United Kingdom) with a standard debridement technique using a hydrogel (Purilon, Coloplast A/S, Peterborough, United Kingdom) in terms of time to debridement of venous (VLU) or mixed arterial/venous (MLU) leg ulcers, as part of standard practice. The Implications of this study This study has obvious implications for both nurses and those patients with long standing wounds and ulcers. Nurses need to know whether or not the treatments they are offering are effective , and also any problems with this type of treatment. Patients in their turn need to know whether a method used is safe, effective and fit for purpose. For a nurse to say ‘They’ve been doing this for hundreds of years’, is not a totally adequate answer with regard to a treatment which has not been scientifically tested , and may be unacceptable to patients. This is especially so as this form of treatment is often only used in cases where other methods have failed, and where there are possible alternatives such as surgical debridement and the use of ultrasound (Leak, 2012) . It is a method which is distasteful to some patients, but which requires less expertise and specialist equipment than some of the other possible methods . Despite lack of lots of research evidence as to whether or not this method is more or less effective than hydrogel (Gray, 2008) it can be used when surgery is not a feasible option because other comorbid conditions are present, or because of other considerations. Debridement of dead tissue from any wound is a long established principle of wound care, because the presence of dead tissue can lead to invasion by bacteria which then acts as a barrier to good healing. Debridement allows living tissue to fill the space. The aim to achieve wound healing, especially of hard to heal wounds, and to prevent further necrosis. Although the results do show the effective ness of the method, and the fact that wounds required a lesser number of dressings changes than in the Purilon group, nurses also need to take into account the findings that the larval therapy group reported more ulcer pain than the other group, although there was a statistically significant difference in wound healing speed and quality . Justification for this study. There have already been a number of studies on this topic. These however could be concentrating on slightly different methods. According to Parnes and Largan ( 2007) there is an increase in the incidence of chronic wounds, perhaps as a result in the rise of Type 2 diabetes and the increase in the average age of the population. These wounds, as well as being unpleasant for the patients, bringing poor quality of life, and also bring with them a number of socioeconomic consequences, what Pownell refers to as ‘the silent epidemic’ ( 2007) and this, together with a desire to bring about the best possible outcomes for patients, can perhaps justify this extensive study, which lists some 32 other studies in its bibliography. Study Design This Welsh study was a comparison between two forms of treatment, the use of BIOfoam, a larval therapy wound treatment, and the use of Purilon gel. It was a randomised cohort study in that all the patients who participated had long standing wounds which needed debridement, and once chosen as part of the study , and full consent obtained, they were allocated randomly to one of the two treatment groups. It was a qualitative study, in that wound healing could be compared between the two groups and quantitative in that careful measurements were taken. There was no control group, that is a group who received no treatment at all: but this can be justified, as all these patients needed to have an improvement in their condition, and the quality of their lives, and both these methods have some degree of efficacy. It was also a longitudinal study in that the wounds took several weeks to heal. There would be need for follow up, as this type of wound, often caused by poor blood circulation and nervous system problems , as a direct result of long standing diabetes, can break down again, as the cause is still present. 64 subjects completed the full course of the study. It is acknowledged by the authors that other methods, such as surgical debridement, might have resulted in quicker wound healings, but it was also pointed out that the use of that method was limited both by the availability of suitably trained personnel, and by the fitness of these particular patients for anaesthesia. Was the design appropriate for the study question? Before beginning the authors considered other studies very carefully. They were then able to calculate the optimum number of patients (31) in each group in order to give each method a really fair trial. This proved to be appropriate, in that the methods used produced good evidence which showed that larval therapy, in this case in the form of a BioFOAM dressing, debrided leg ulcers caused both by venous stasis ( VLU) and those caused by a combination of venous and arterial problems ( MLU), more speedily than if hydrogel was used on very similar wounds. We are not told how long standing these wounds were, how large they were or the general state of the patient’s health. The authors stress that there results should be only taken as showing trends Wounds treated were those which had at least 25% of dead tissue in them at the start of the trial. Every effort was made to avoid bias in that blind assessors, that is those who did not know what treatment was being used, saw the wounds each time dressings were changed and assessed them for healing, and also when they felt that full debridement had taken place. Photographs for later confirmation were also taken. Full debridement, the endpoint, was defined as when there was a “clean wound bed that no longer required a debriding agent.” Sample The study was carried out by researchers from the Cardiff Medical School’s Wound Healing Research Unit. Recruitment proved to be difficult and the initial desired sample size was not met (Munch et al, page 50, 2013). The researchers analysed the data of 88 possible subjects who had leg ulcers and 64 of these completed the study. Of these, of those treated with larval therapy, all but on reached a state of total debridement, whereas only 34.4 % of those where the hydrogel had as good a result. We are not told the ages or sexes of the patients, or their more general state of health, and any diagnosis or reason for the ulcers forming. The patients were recruited from a number of sources, both from inpatients and out patients, from community leg ulcer clinics, and from the cases treated by district nurses. Ethics. Participation in this study was voluntary and fully informed written consent was obtained from each participant. All the required permissions were obtained from Oxfordshire Independent Research Ethics Committee, as well as from local research and development departments. Patients were assured that their care would not be adversely affected by their decision as to whether or not to participate. The study was carried out according to:- Declaration of Helsinki Ethical Principles for Medical Research Involving Human Subjects (52nd WMA General Assembly, Edinburgh, Scotland, October 2000), the Good Clinical Practice Consolidated Guideline approved by ICH and SIs 1031 (2004), 1928 (2006) and any applicable national and local laws and regulations. ( Mudge et al,page 45, 2013). Frequency of Outcome Measurement. Wounds were assessed before the trial began, and then every time they required clean dressings over a 21 day period, or until full debridement was achieved, or until the patient left the trial for whatever reason. Those receiving hydrogel treatment were found to require clean dressings more often than those undergoing larval treatment. They were assessed every three or four days. There was a final decision that debridement had, or had not, taken place. Follow-up was also required, as the underlying causes of these ulcers were still present. These outcomes were relatively easy to measure and valid according to the aims of this study. The amount of slough present was assessed, as were the size of ulcers, and the final debridement would show a clean wound bed, ready for healing. Was the Intervention Used Described in Detail? The procedures followed are explained in detail ( Mudge et al, 2013, page 43). The chosen treatment was applied and the wounds were then checked each time the wounds were dressed, every 3 or 4 days, and assessed for size and the amount of debridement which had taken place. Both the skin surrounding the ulcers and the wound beds were included in these assessments. Once full debridement was achieved, or after 21 days, a further assessment was made after two weeks. Further infection is not described. Co-interventions are not described, but if these did occur it is possible that these could have had an effect upon the results. These would most likely be diabetic patients though, and presumably would be receiving some treatment for that condition. These ulcers tend to occur in older people, and many such people have concurrent conditions, each of which may require treatment, including such things as antibiotics , which could make a difference in healing rates. Could this intervention be carried out as part of normal nursing practice? Both methods were used by ordinary nurses in a variety of situations, both in and out of hospital, so have been proved to be useful in normal; nursing practice . Also these are well established methods of treatment. BioFoam was developed in 2010 ( Synbra, undated), but relies on ideas which go back many hundreds of years. Purilon can be applied easily, even using only one hand ( Purilon Gel, undated) Hydrogel products similar to Purilon were developed in the 1960s, (Lay-Flurrie, 2004) . Thomas and Leigh describe its use in wound treatment (1998). The majority of the nurses in this study rated us of both types of dressing as either ‘easy’ or ‘very easy ( Mudge et al page 49, 2013). What were the results? Were they statistically significant? At the beginning of the trial data was checked to ensure that the groups were as equal as possible in order to ensure fairness. Statistically there was no difference between the two groups. When it comes to differences in the appearance or condition of the ulcers there were no statistically significant differences in the ulcers by intervention groups at the time of the final assessment. Pain differences were statistically significant, with the BioFoam group stating higher pain levels on average. It was later found, after a further fortnight, that those wounds treated by using BioFoam were statistically significantly more likely to have broken down once more. The use of larvae ( Biofoam) did remove necrotic tissue in a statistically significant lesser period than when hydrogel was used. It was felt that these results show the method to be effective, and that if pain control is correctly used and patients are correctly educated , the method’s use would be further enhanced. Clinical Significance of Results. These results show that these seemingly intractable ulcers can be treated successfully using larval treatment more quickly than if another method is used. Also dressings required changing less often. This means both that nurses need to spend less time, but also that patient’s wounds are returned to a state of full debridement more quickly, thus enhancing the individual quality of life. The other group had less successful outcomes, though they generally experienced less pain. They also needed more frequent attention and the patient’s would not have felt themselves to be so encouraged towards better health. Conclusion The main findings were that larval therapy is successful in bringing about full debridement in almost every case, in a shorter period than when hydrogel was used, and is easy to carry out. The implications are that this should be a method of choice , providing pain issue scan be dealt with. Quality of Research. This was carefully planned medical research into an increasingly important topic, because of rising numbers of these wounds. The processes and results are laid out in an orderly fashion, so that they can be followed in practice, problems encountered are discussed, and the results are easy to understand. How the appraisal process has broadened my understanding of assessing the quality of published research This exercise has shown clearly that any appraisal needs to be done in a systematic way such as that outlined in the McMasters Critical Review forms. This however was aimed at Quantitative studies, and this one mixes quality and quantity. References Lay-Flurrie, The properties of hydrogel dressings and their impact on wound healing Leak, K., How to... Ten top tips for wound debridement, Wounds International , 22nd February 2012, http://www.woundsinternational.com/practice-development/how-to-ten-top-tips-for-wound-debridement Mudge,E., Price, P., Walkley,N., Keith,H., A randomized controlled trial of larval therapy for the debridement of leg ulcers: Results of a multicenter, randomized, controlled, open, observer blind, parallel group study, Wound Repair and Regeneration Volume 22, pages 43- 51, 2013 for the Wound Healing Society Parnes,A., and Largan, K., Larval Therapy in Wound Management: A Review, International Journal of Clinical Practice, MedScape Multispeciality http://www.medscape.com/viewarticle/554795_1 Pownall M, editor. Skin breakdown: the silent epidemic. Hull, UK: Smith & Nephew Healthcare Ltd., 2007. Purilon Gel, undated, http://www.medplast.lt/pdf/CP_Purilon_Gel.pdf Synbra, BioFoam, undated, http://www.biofoam.nl/uploads/Press%20release%20BioFoam%20C2C%202009-12.pdf Thomas,S. and Leigh, I., Wound dressings. In: Leaper, D. and Harding, K. (eds) Wounds: Biology and management. Oxford: Oxford University Press 1998. Read More