Compression therapy of leg ulcers with PAOD
Phlebology 2014, Vol. 29(1S) 7–12 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0268355514529507 phl.sagepub.com
Andrea Ladwig1, Hermann Haase1, Jens Bichel2, Jan Schuren2 and Michael Ju¨nger1
Abstract Objectives: To assess the clinical safety of a new short-stretch 2-layer compression system (3Mtm Cobantm 2 Lite) in patients with peripheral arterial occlusive disease (PAOD). This system combines a low resting pressure with a high working pressure. Methods: A pilot study was performed in 15 subjects with moderate PAOD, i.e. an ABPI of 0.5-0.8. Co-existing chronic venous insufficiency or leg ulcer was not mandatory. All subjects received the compression system which was reapplied at each study visit (days 1, 2, 3, 4, 7, 10, 14). The safety parameters were: sub-bandage pressure immediately after application, pressure-related skin damage, hypoxia-related pain, and adverse events. A product comfort questionnaire was completed at the last visit. Results: The average sub-bandage pressure of 30 mmHg defined by the protocol was achieved. No pressure-related skin damage or hypoxia-related pain was found. The reported adverse device effects were as expected for compression therapies, including dry skin and pruritus. The product comfort questionnaire completed by the subjects showed a good tolerability profile. Conclusion: The short-stretch 2-layer compression system (3Mtm Cobantm 2 Lite) was safe and well tolerated in subjects with moderate PAOD.
Keywords Leg ulcer with moderate PAOD, 2-layer short-stretch compression therapy, pressure-related skin damage, hypoxiarelated pain
Introduction In Western societies, the prevalence of ﬂorid or resolved leg ulcer is estimated around 0.7 %.1 The most frequent aetiologies include venous disease followed by arterial insuﬃciency, diabetes and rheumatoid arthritis. Chronic venous insuﬃciency (CVI) is found in about one third of the Western population and its prevalence increases with age.1 As elderly people often suﬀer from peripheral arterial occlusive disease (PAOD), a coincidence of both peripheral vascular diseases is a common ﬁnding.3 Compression therapy is the principal mode of treatment for leg ulcer. Numerous beneﬁts of this therapy have been described, including decrease in oedema, acceleration of venous backﬂow, decrease in venous volume, reduction in venous reﬂux, and lymph-drainage.4 Hence, the use of compression therapy is an agreed standard in leg ulcer caused by CVI. On the other hand, the use of compression therapy in patients with PAOD is still debated in the scientiﬁc
community, as the application of external compression is assumed to potentially reduce the local perfusion of the leg. To avoid the risk of under-perfusion, a variety of treatment recommendations were oﬀered which mainly referred to the applied level of compression.5,6,7,8,9 In recent studies in patients with moderate PAOD, indicated by an Ankle Brachial Pressure Index (ABPI) between 0.5 and 0.8, an average pressure of 30 to 32 mmHg measured at the B1 location was reported to be safe and well tolerated.10,11
1 University of Greifswald, Fleischmannstrasse 42/43, Greifswald, Germany 2 3M Deutschland GmbH, Neuss, Germany
Corresponding author: Michael Ju¨nger, University Greifswald, Fleischmannstrasse 42/43, Greifswald, Germany. Email: [email protected]
Clinicaltrials.gov Identifier: NCT00854516
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Regarding the eﬀectiveness of compression therapy, it was shown in a recent clinical study that the stiﬀness of the compression system plays a central role. The ejection volume and ejection fraction from the peripheral venous system following muscle activity were much higher if inelastic systems were used.12 The authors assumed that inelastic compression systems lead to pressure peaks during walking, comparable to a pneumatic pressure pump. Moreover, the muscle systoles during walking with an inelastic compression system in situ may block venous reﬂux intermittently and thus imitate competent venous valves. To diﬀerentiate between elastic and inelastic systems, the static stiﬀness index (SSI) is used. The SSI is determined by the diﬀerence in pressure under the compression system when comparing supine position to standing position. A diﬀerence of more than 10 mmHg classiﬁes a compression system as stiﬀ bandage.13 Because of a signiﬁcant correlation between the quotient working pressure to resting pressure, compression bandages with a higher quotient improve venous drainage best.14 In the present article, we are reporting about a pilot study that was conducted with a new inelastic, shortstretch system, 3MTM CobanTM Lite Compression System (hereafter Coban 2 Lite), which was developed for the use in leg ulcer and concomitant PAOD. This safety trial was performed to gain data about the tolerance with regard to clinical symptoms and acral arterial perfusion in patients with impaired peripheral arterial blood supply. The new bandage provides a thin, conforming inelastic sleeve, which combines a reduced resting pressure with the required stiﬀness in standing position. This combination was expected to be associated with a high rate of tolerability, which is mainly dependent on the reduced resting pressure.15
Methods This open-label, single-centre, prospective pilot study was conducted at the UNIVERSITY HOSPITAL in Greifswald, Germany. Prior to study start, nurses at the study site in Greifswald were trained to apply compression, providing sub-bandage pressure values around 30 mmHg at the B1 position. The protocol was approved by the Ethics Committee of the Ernst-Moritz-Arndt-University. Study participants granted written informed consent prior to inclusion into the study. Subjects were included to the study if they were 18 years or older, suﬀering from PAOD with an ABPI at the investigational leg between 0.5 and 0.8, able to walk and being co-operative, willing to give written informed
consent prior to study entry and willing to comply with the study protocol. Exclusion criteria were: general conditions which in the opinion of the investigator did not allow for compression therapy, paralysis of the study leg, mood altering substances if started or signiﬁcantly changed within two weeks prior to enrolment, signiﬁcant unstable coagulopathy, participation in any other prospective clinical study that could potentially interfere with this study, and known allergies against Coban 2 Lite. The study started with visit 0 (screening and treatment initiation) on day 0 and ended with visit 7 on day 14. All subjects received treatment with Coban 2 Lite which includes a comfort layer bandage and a compression layer bandage. The protocol contained detailed instructions on how to apply the 2 bandages. For the compression layer, the instructions asked for ‘full stretch’ to be reached by maintaining consistent full stretch throughout the wrapping process and by winding with 50% overlap. Wounds were to be covered with a primary dressing before applying the comfort layer. For precautions, the protocol speciﬁed that the compression system should be changed when the wrap was not conforming to the leg circumference. Subjects were advised to notify the study site if they experienced severe pain, numbness, tingling and swelling or blue/ pale colour of toes. The system stayed in place for 1 up to 4 days according to scheduled study visits. The system was reapplied by the study personnel at 6 interval treatment visits (days 1, 2, 3, 4, 7, and 10). On study day 14, the study was ﬁnished with an end of study visit. At each clinical visit safety assessments were performed. Parameters to evaluate safety included: 1. clinical signs of early skin damage, eventually substantiated by measuring the transepidermal water loss (TEWL); 2. photodocumentation in case of skin damage; 3. documentation of painful sensations as potential signs of tissue under perfusion; 4. Sub-bandage pressure measurements and 5. collection of adverse events. In addition volume evaluations of the lower legs were performed at the ﬁrst and last study visit and a product comfort questionnaire was completed at the end of the study. TEWL as an early symptom of skin damage was to be measured with the Tewameter (Courage & Khazaka, Cologne, Germany) only if skin damage was clinically visible. The TEWL was to serve as a diagnostic tool to substantiate these potential early clinical signs. Typically, TEWL is increased in areas of irritated skin. Digital photodocumentation was planned in case of clinically visible skin damage. Immediately after each bandage application the subbandage pressure was measured at B1 which is the proximal end of the tendon of the calf muscle where the muscle interlocks with the Achilles tendon13 with
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Ladwig et al.
the PicoPress Compression Measurement System (Microlab Elettronica, Ponte S Nicolo`, Italy). The circumferences and the volume of the leg were determined by Image 3D (Bauerfeind Phlebologie, Zeulenroda, Germany). The statistical method was deﬁned as follows: Aggregate data were collected using an Access database. This included all measurements and the product comfort questionnaire with 8 criteria. The product comfort questionnaire data was evaluated using a frequency table. Statistical calculations and graphic generation were done with Excel using Access queries. Exploratory testing for diﬀerence was done at a 5% level of signiﬁcance. All adverse events were summarised according to severity and relation to study.
Results 15 subjects with PAOD were included in the study of which 7 were female and 8 were male. At the time of inclusion into the study, women had a mean age of 74.1 10.1 (average standard deviation) years while men were 71.4 10.5 years old. 6 of the 15 enrolled subjects suﬀered from coincident chronic venous insuﬃciency. Among these 6 subjects, 2 were female and 4 were male. 3 subjects had an active leg ulcer at the study start. However, this study with a maximum observation period of 14 days was not expected to provide relevant information about the clinical course of these ulcers. The ABPI was 0.5 and