Archived Comments for:
Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial
Re: Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial
Pascal Steenvoorde, Rijnland Hospital Leiderdorp, The Netherlands
20 October 2006
Pascal Steenvoorde
psteenvoorde@zonnet.nl
Rijnland Hospital Leiderdorp, the Netherlands
P. Steenvoorde MD MSc(1,2), L.P. van Doorn MA(2), C.E. Jacobi PhD(3), A.A. Kaptein PhD(4), Oskam MD PhD(1,2)
From the department of Surgery(1) Rijnland Hospital Leiderdorp, the Rijnland Wound Clinic(2) Rijnland Hospital Leiderdorp, The Department of Medical Decision Making(3), Leiden University Medical Center and the Unit of Psychology(4), Leiden University Medical Center, The Netherlands.
We would like to congratulate Petherick and co-authors on their recently published work on acceptability on larval therapy [1]. In the article they present a method on how to measure patient acceptability for larval therapy. The method they are using, however, is a biomedical approach, which does not leave room for emotions and considerations from patients. These aspects seem to be at least equally important in patient acceptability of larval therapy.
We were surprised by the high number of refusals the authors found in their study: approximately 25% (8/35) of participants would not even consider the use of larval therapy. We believe this is quite high percentage. In our own experience this refusal rate is indeed below the stated 10% (in our series from August 2002 until 1 January 2006, only 1 out of 102 patients refused, i.e. only 1%) [2]. In our experience some patients are terrified after the initial proposal of maggot therapy, but after adequate information most of them agreed. This information does not only mean written information, but also includes oral information. In our clinic, the family is always allowed and also encouraged to see the actual maggots being placed in the wound. We have made a photo-album of one of our patients who was given maggot therapy; nowadays we show the pictures that were taken during this treatment to new patients, in order to make maggot therapy less frightening. In the study by Petherick et al. the patients were asked if they would consider larval therapy; 8/35 stated they would never. These participants were not asked any further questions about the use of larval therapy, which we believe to be a gap in their study. We believe a large percentage of these patients would consider undergoing maggot therapy if they had the proper information regarding the therapy [3]. Do these patients know what they object to? Perhaps they only object to the idea of maggot therapy. For if the only information the patients has are his own feelings, these are certainly becoming facts for the patient. Here the emotions and considerations of the patients should have a place in the research. We would like to suggest further studies should be done on the refusal group. Another factor might be the aetiology of the wound, in the study by Petherick et al. only venous leg ulcer patients where included. For example in other patient categories like diabetic foot problems, the risk of a major amputation is higher; this feared outcome might influence diabetic patients undergoing maggot therapy earlier. However this is speculative, further studies regarding this statement are needed.
Furthermore the authors make the presumption that the bagged technique is more acceptable to the patient since there is less chance of the larvae to escape from the wound. We would like to debate this, escape rates (11-12%) were virtually the same for the bagged and the loose technique in an earlier published study [3]. In the same publication (85% of patients treated with the loose technique), we showed about 90% of patients would agree on a second maggot treatment if necessary; also, the patients would suggest this therapy to others as well, irrespective of their own result with maggot therapy. In a phenomenological study the experience of larval therapy was not as scary as imagined [4].
We believe that patient acceptability is an important factor in any treatment, especially in maggot therapy. Based on a reduced effectively if contained [5, 6], our standard application is the loose technique. Patient preference [7] and the use of oral anti-coagulation therapy [8] are among the factors to consider when using the contained technique. We believe, however, that the patient should be advised the best technique, suitable for their wound. It would be an interesting study if the patients are well informed about all three treatment modalities (loose, contained and hydrogel), if they were informed about effectiveness, complications and adverse effects and then ask them which method of treatment they would prefer. That study would, in our opinion, answer the question of which technique is the preferred one in this patient category, and would answer the question of patient acceptability of maggot therapy.
References
1. Petherick ES, O'Meara S, Spilsbury K, Iglesias CP, Nelson EA, Torgerson DJ. Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial. BMC Med Res Methodol 2006;1:43.
2. Steenvoorde P, Jacobi CE, Doorn Lv, Oskam J. Maggot Debridement Therapy of infected ulcers: patient and wound factors influencing outcome. Ann Royal Coll Surg Eng accepted for publication. 2006.
3. Steenvoorde P, Budding TJ, Engeland Av, Oskam J. Maggot therapy and the 'YUK factor'; an issue for the patient? Wound Repair Regen. 2005;13:350-352.
4. Kitching M. Patient's perceptions and experiences of larval therapy. J Wound Care. 2004;13:25-29.
5. Thomas S, Wynn K, Fowler T, Jones M. The effect of containment on the properties of sterile maggots. Br J Nurs, Tissue Viability Supplement. 2002;11:S21-S28.
6. Steenvoorde P, Jacobi CE, Oskam J. Maggot Debridement Therapy: Free-range or contained? An In-vivo study. Adv Skin Wound Care. 2005;18:430-435.
7. Steenvoorde P, Oskam J. Use of larval therapy to combat infection after breast-conserving surgery. J Wound Care. 2005;14:212-213.
8. Steenvoorde P, Oskam J. Bleeding complications in patients treated with Maggot Debridement Therapy (MDT). Letter to the editor. IJLEW. 2005;4:57-58.
Competing interests
I declare that I have no competing interests
Response to comments from Steenvorde and Colleagues
Emily Petherick, Department of Health Sciences, University of York.
7 November 2006
We thank Steenvorde and colleagues for their comments on our recently published work(1). Our study was undertaken to examine what preconceptions leg ulcer patients had concerning the use of larval therapy, contained using two different methods. This was then used to inform the sample size calculation of a randomised trial. Steenvorde raises an interesting point regarding whether patients do actually know what they are objecting to when they refuse the idea of larval therapy (2). In future work adjunct to the VenUS II trial we will be specifically interviewing patients who refused to and those that did take part in the trial of larval therapy to qualitatively explore their reasons for this. In addition we will also be interviewing staff to explore their experiences of using larval therapy and their influence on the attitudes of patients towards the therapy.
We also concur with Steenvorde and colleagues that patients should be advised of the potential risk and benefits of the different methods of larval therapy application. We think that our trial (3) will provide much needed evidence to help inform both patient and practitioner decision making using larval therapy for the treatment of venous leg ulcers.
1. Petherick ES, O'Meara S, Spilsbury K, Iglesias CP, Nelson EA, Torgerson DJ. Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial. BMC Med Res Methodol 2006;1:43.
2. Steenvoorde P, van Doorn LP, Jacobi CE, Kaptein AA, Oskam. Re: Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial BMC Med Res Methodol 2006;1:43.
3. Raynor P, Dumville J, Cullum N: A new clinical trial of the effect
of larval therapy. J Tissue Viability 2004, 14:104-5.
Re: Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial
20 October 2006
Pascal Steenvoorde
psteenvoorde@zonnet.nl
Rijnland Hospital Leiderdorp, the Netherlands
P. Steenvoorde MD MSc(1,2), L.P. van Doorn MA(2), C.E. Jacobi PhD(3), A.A. Kaptein PhD(4), Oskam MD PhD(1,2)
From the department of Surgery(1) Rijnland Hospital Leiderdorp, the Rijnland Wound Clinic(2) Rijnland Hospital Leiderdorp, The Department of Medical Decision Making(3), Leiden University Medical Center and the Unit of Psychology(4), Leiden University Medical Center, The Netherlands.
We would like to congratulate Petherick and co-authors on their recently published work on acceptability on larval therapy [1]. In the article they present a method on how to measure patient acceptability for larval therapy. The method they are using, however, is a biomedical approach, which does not leave room for emotions and considerations from patients. These aspects seem to be at least equally important in patient acceptability of larval therapy.
We were surprised by the high number of refusals the authors found in their study: approximately 25% (8/35) of participants would not even consider the use of larval therapy. We believe this is quite high percentage. In our own experience this refusal rate is indeed below the stated 10% (in our series from August 2002 until 1 January 2006, only 1 out of 102 patients refused, i.e. only 1%) [2]. In our experience some patients are terrified after the initial proposal of maggot therapy, but after adequate information most of them agreed. This information does not only mean written information, but also includes oral information. In our clinic, the family is always allowed and also encouraged to see the actual maggots being placed in the wound. We have made a photo-album of one of our patients who was given maggot therapy; nowadays we show the pictures that were taken during this treatment to new patients, in order to make maggot therapy less frightening. In the study by Petherick et al. the patients were asked if they would consider larval therapy; 8/35 stated they would never. These participants were not asked any further questions about the use of larval therapy, which we believe to be a gap in their study. We believe a large percentage of these patients would consider undergoing maggot therapy if they had the proper information regarding the therapy [3]. Do these patients know what they object to? Perhaps they only object to the idea of maggot therapy. For if the only information the patients has are his own feelings, these are certainly becoming facts for the patient. Here the emotions and considerations of the patients should have a place in the research. We would like to suggest further studies should be done on the refusal group. Another factor might be the aetiology of the wound, in the study by Petherick et al. only venous leg ulcer patients where included. For example in other patient categories like diabetic foot problems, the risk of a major amputation is higher; this feared outcome might influence diabetic patients undergoing maggot therapy earlier. However this is speculative, further studies regarding this statement are needed.
Furthermore the authors make the presumption that the bagged technique is more acceptable to the patient since there is less chance of the larvae to escape from the wound. We would like to debate this, escape rates (11-12%) were virtually the same for the bagged and the loose technique in an earlier published study [3]. In the same publication (85% of patients treated with the loose technique), we showed about 90% of patients would agree on a second maggot treatment if necessary; also, the patients would suggest this therapy to others as well, irrespective of their own result with maggot therapy. In a phenomenological study the experience of larval therapy was not as scary as imagined [4].
We believe that patient acceptability is an important factor in any treatment, especially in maggot therapy. Based on a reduced effectively if contained [5, 6], our standard application is the loose technique. Patient preference [7] and the use of oral anti-coagulation therapy [8] are among the factors to consider when using the contained technique. We believe, however, that the patient should be advised the best technique, suitable for their wound. It would be an interesting study if the patients are well informed about all three treatment modalities (loose, contained and hydrogel), if they were informed about effectiveness, complications and adverse effects and then ask them which method of treatment they would prefer. That study would, in our opinion, answer the question of which technique is the preferred one in this patient category, and would answer the question of patient acceptability of maggot therapy.
References
1. Petherick ES, O'Meara S, Spilsbury K, Iglesias CP, Nelson EA, Torgerson DJ. Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial. BMC Med Res Methodol 2006;1:43.
2. Steenvoorde P, Jacobi CE, Doorn Lv, Oskam J. Maggot Debridement Therapy of infected ulcers: patient and wound factors influencing outcome. Ann Royal Coll Surg Eng accepted for publication. 2006.
3. Steenvoorde P, Budding TJ, Engeland Av, Oskam J. Maggot therapy and the 'YUK factor'; an issue for the patient? Wound Repair Regen. 2005;13:350-352.
4. Kitching M. Patient's perceptions and experiences of larval therapy. J Wound Care. 2004;13:25-29.
5. Thomas S, Wynn K, Fowler T, Jones M. The effect of containment on the properties of sterile maggots. Br J Nurs, Tissue Viability Supplement. 2002;11:S21-S28.
6. Steenvoorde P, Jacobi CE, Oskam J. Maggot Debridement Therapy: Free-range or contained? An In-vivo study. Adv Skin Wound Care. 2005;18:430-435.
7. Steenvoorde P, Oskam J. Use of larval therapy to combat infection after breast-conserving surgery. J Wound Care. 2005;14:212-213.
8. Steenvoorde P, Oskam J. Bleeding complications in patients treated with Maggot Debridement Therapy (MDT). Letter to the editor. IJLEW. 2005;4:57-58.
Competing interests
I declare that I have no competing interests
Response to comments from Steenvorde and Colleagues
7 November 2006
We thank Steenvorde and colleagues for their comments on our recently published work(1). Our study was undertaken to examine what preconceptions leg ulcer patients had concerning the use of larval therapy, contained using two different methods. This was then used to inform the sample size calculation of a randomised trial. Steenvorde raises an interesting point regarding whether patients do actually know what they are objecting to when they refuse the idea of larval therapy (2). In future work adjunct to the VenUS II trial we will be specifically interviewing patients who refused to and those that did take part in the trial of larval therapy to qualitatively explore their reasons for this. In addition we will also be interviewing staff to explore their experiences of using larval therapy and their influence on the attitudes of patients towards the therapy.
We also concur with Steenvorde and colleagues that patients should be advised of the potential risk and benefits of the different methods of larval therapy application. We think that our trial (3) will provide much needed evidence to help inform both patient and practitioner decision making using larval therapy for the treatment of venous leg ulcers.
1. Petherick ES, O'Meara S, Spilsbury K, Iglesias CP, Nelson EA, Torgerson DJ. Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial. BMC Med Res Methodol 2006;1:43.
2. Steenvoorde P, van Doorn LP, Jacobi CE, Kaptein AA, Oskam. Re: Patient acceptability of larval therapy for leg ulcer treatment: a randomised survey to inform the sample size calculation of a randomised trial BMC Med Res Methodol 2006;1:43.
3. Raynor P, Dumville J, Cullum N: A new clinical trial of the effect
of larval therapy. J Tissue Viability 2004, 14:104-5.
Competing interests
None to declare.