Textile Composition, Not Number of Layers, Impacts Interphase Pressure and Static Stiffness Index: A Pragmatic, Comparative Analysis of the In Vivo Interphase Pressure of 7 Different 2-Layer Cohesive Bandage Kits in Healthy Volunteers

Compression is the cornerstone in the conventional management of chronic venous disease (CVD), venous leg ulcers (VLU), and edema of any origin. The benefits of compression, including both physiological and biochemical effects on the circulatory systems (arterial, venous, and lymphatic) and the integument system, are well documented in the literature. With proper application, a compression bandage has been documented to reduce edema,^1-4 normalize venous function,^2,4,5 improve arterial pulse width,^6,7 optimize healing of VLUs,^1,8-10 reduce presence of inflammatory mediators and symptoms,^2,11-15 reduce episodes of recurrent cellulitis,^16-18 promote resolution of trophic changes,^13,19 and reduce pain.^2,19,20

Although there is a plethora of evidence touting the benefits of compression,^{3,8,9,14,16,20-27} a universal dosage or a specific textile combination that is superior has yet to be identified.²⁰ Despite the ambiguity regarding the exact ‘therapeutic dosage’,²⁰ it persists as the singularly most referenced criteria for compression prescription.^{3,4,8,19,22,24,27-32} The dogma of dosage as the sole determinate of efficacy of a compression application disregards cited hemodynamically relevant compression textile characteristics including static stiffness^{3,4,9,22,27,30,32-39} and containment.^{4,27,32,36-38} Additionally, recent research has highlighted a third characteristic of compression—distribution of compression pressure across the limb and/or wound—which may also impact the efficacy of a compression application.^32,38,40,41

The use of compression, in the form of disposable, pre-packaged, compression bandages kits is a standard of care in the management of CVD, VLUs, and edema of any origin in the United States (US). These compression bandage kits are readily available, utilized by both skilled and untrained clinical providers alike, across the continuum of care. In the literature and amongst clinicians in their day-to-day practice and documentation, these compression applications continue to be speciously categorized in 1 of 3 ways: the number of layers applied, the elasticity (short stretch vs. long stretch) of either one component or the system as a whole, and/or the adhesive nature (cohesive, adhesive, non-adherent) of one of the textile components included. As detailed in Table 1 and 2, there are numerous overlaps and voids in these specific nomenclatures confounding the interpretation and practical utilization of clinical studies, Cochrane reviews, and clinical practice guidelines.^{8,20-22,42-44} 

Despite the omnipresence of these kits, review of the current literature offers the inquiring clinician little specific guidance for selection of a specific compression bandage kit beyond generic descriptive terms referencing the number of layers or type of textile contained within the wrap. To clarify, a ‘2-layer’ system should rightfully be referenced as a ‘2-component’ system, as technically when 2 components are applied with any overlap, as is the case with the standard spiral application, it is no longer 2-layer but rather 4 layers of textiles applied across the surface of tissue in the areas of overlap. In some areas, such as the ankle where often a figure 8 is applied, there may be 6 layers, comprised of 2 different textiles.

Furthermore, referencing a product as 2-layer disregards the unique characteristics of each individual layer alone, as well as how the 2 layers interact as a unit. The reader will recall that although an individual component may be technically elastic in nature, when applied in layers, or in combination with other textiles, the individual characteristics of a textile can no longer be assumed.^20,45 As an example, the generically referenced 4-layer bandage system that contains an elastic textile as one of the layers, should not be referred entirely as elastic. When used in combination with other textiles, layered one on top of the other, the friction that develops between the layers produces a compression profile that is analogous to a short stretch or ‘inelastic’ textile.^20,35,45-47

A second hinderance for clinicians seeking guidance for the evidence-based selection and utilization of boxed compression sets is the inconsistent and incomplete availability of the compression profile, both the resting interface pressure (IP) and static stiffness index (SSI), provided by the manufactures for each individual product as well as the system as a whole. The IP, commonly referenced as the dosage is the pressure (mmHg) between the compression system and the limb.^20,48 The SSI is the difference between the working (standing) and resting (supine) pressures.^20,48 If SSI >10, the compression system has a high stiffness and is referenced as inelastic in nature. When SSI <10 the system is considered to be elastic.⁴⁸ This information is not universally provided in pamphlets packaged with the kits, nor is it easily found on the internet. Furthermore, in vivo assessment of IP and SSI is rarely documented during clinical trials evaluating the compression boxed sets currently available for use in the US. The omission of this data significantly limits the interpretation of comparative research between similarly referenced compression systems. As such, review of the literature for specific evidence to differentiate between compression bandage kits leaves clinicians and consumers perplexed as to how to discriminate between the multiple compression bandage kits, or bandage alternatives, which are marketed as equivalent according to the referenced terminology as outlined in Table 1^20,45,49 and Table 2.^8,20,49

A final hinderance to an evidence-based approach to clinical compression selection amongst these compression bandage kits is the lack of control over product choice. Across the continuum of care, it is cost and formulary that often dictate product availability and utilization. Clinicians are forced to use a product based on price and/or formulary contract. Alternatively, the clinician may even resort to using individually packaged textiles to fabricate their own layered system to save money. Relative to the latter, it needs to be acknowledged that these creative liberties, albeit viewed as cost-efficient, and when applied by a skilled practitioner even effective, do not guarantee a prescriptive dosage based on number of layers.^45,46,50 Clinicians should be aware that bandage sets that are similar in appearance, or even in the number of layers, (applied in a similar pattern), as is the case with multiple box compression applications, does not guarantee a set dosage delivered; and more importantly, the comprehensive compression profile (IP, SSI, and distribution) may not be the same between any 2 products even if the components appear similar
in construction.

The absence of evidence demonstrating objective differences between boxed compression bandage kits beyond those provided by the manufacturers was the impetus for this independent study. Clinically, the author has observed subjective differences with regards to efficacy and patient subject feedback regarding comfort with different 2-layer compression box applications. Nevertheless, commercially available 2-layer cohesive compression bandage kits are viewed as the same based on a generic description of the product by number of layers. This is despite overt differences in textile construction, indications for use, application techniques, and marketed therapeutic dosage provided by the manufacturers via package inserts. The unique characteristics of the 7, 2-layer cohesive compression bandage sets commercially available in the US assessed in the study are detailed in Table 3. The aim of this research project was to document the in vivo IP and SSI measured, immediately upon application, in 2 locations on the leg, in 2 positions. The null hypothesis was that there will be no difference in the measured IP or SSI between the 7, 2-layer cohesive compression box sets.

This study was approved by the Atrium Health Internal Review Board and Nova Southeastern University Internal Review Board. A sample of convenience was utilized for this study. Ten healthy subjects (6 male, 4 female) participated in this study after signing the informed consent form. Demographics for the study sample are detailed in Table 4. The ankle brachial pressure index (ABPI) of all study subjects was measured prior to initiation of the study to ensure an ABPI >0.8, indicating a healthy arterial system to support the use of external compression.

A single clinician with 20 years of experience working daily in the management of lymphedema and chronic non-healing wounds applied the compression bandage kits. Compression bandage kits were applied in random order on non-consecutive days over a 4 -week period. The application technique described by the manufacturer’s recommendations referenced from the written information supplied in the compression bandage kits was followed. In addition, prior to initiation of the study, the clinician reviewed each manufacturer’s bandage application instructional video online. In-person training was not an option due to ongoing COVID restrictions.

Study Protocol: After signing informed consent, the subject was placed in the supine position for 5 minutes. While the subject rested, the PicoPress(Microlab)sensor was positioned on the right leg. The sensor is a flat, flexible, air-filled transducer, and was attached to the medial side of the right lower leg as recommend by Partsch et al,^30,45 at locations B1 and C. On the lower leg, B1 is noted to be 10 to 15cm above the medial malleoli, where the tendinous part of the gastrocnemius muscle turns into the muscular part. Point C is located on medial side of the leg, at the calf’s greatest circumference. The circumference and distance from the medial malleoli were measured and documented to ensure that with each application on subsequent days placement of the pressure senor would be the same.

A compression bandage kit was selected at random and applied with the subject in supine position. IP measurements were documented in 2 successive positions: supine with heel resting on a towel roll to prevent the calf from touching the table, and standing, feet apart at pelvis width with weight equally distributed. Measurement of IP was documented when the value stabilized for 2 minutes in supine and after performance of 5 toe raises in standing. After the measurement in the standing position was recorded, the subject returned to the supine position, the bandage was removed, and the subject remained in the supine position resting for 2 minutes. The procedure was repeated for the same bandage system, on the same subject (20 sets of measurements for each wrap). Assessment of each compression system was completed on all subjects prior to initiating assessment of the next compression bandage system.
 

Data Analysis: Statistical analysis of the outcome data was performed utilizing a repeated measures analysis of variance (ANOVA) to determine the effects of the bandage type on IP and SSI for each of the measurement points, and according to the subject’s position. The SSI was calculated by subtracting the standing pressure from the supine pressure for both the B1 and C locations (SSI = IP standing – IP supine). Post hoc analyses were performed by Tukey and Bonferroni test to identify significant differences. A regression model, including the main effect of the wrap and the subject, was performed for the supine measurements at B1 and C. The dispersion of the recorded pressures within the study population (dispersion between subjects) was assessed by the coefficient of variations.

The individual in vivo IP measured at B1 and C in both supine and standing position for the 7, 2-component boxed compression sets are detailed in Table 5. The in vivo IP measured at B1 in the supine position varied from 50.1 mmHg (±5.33) to 73.7 mmHg (±13.44). The in vivo IP measured at C in the supine position varied from 53.2 mmHg (±7.6) to 69.3 mmHg (±10.6). Bonferroni post-hoc analyses demonstrated, with 95% confidence interval, there was a significant difference between wraps and placed them into 5 groups for the IP measured at B1, and 3 groups for measurements taken at C. This is illustrated in Tables 6 and 7.

The SSI measured at B1 ranged from 12.0 mmHg (± 5.4) to 6.6 mmHg (± 6.7) (Table 8). Two unusual observations or outliers were removed from the analysis. Three post hoc analyses of the SSI found significant differences between the wraps and placed them into 3 groups. Wrap 1 had the highest SSI (11.35 ± 5.36). Wrap 6 and wrap 4 had the lowest (7.45 ± 4.15  mmHg and 7.0 ± 3.63  mmHg respectively). A low SSI equates to a low variation in bandage stretch, leading to a low variation in bandage tension and therefore reduced variation in interface pressure. Conversely, a high relative stiffness equates to marked variation in bandage tension and thus IP, even with a relatively small variation in bandage stretch. A regression model including the main effects of the wrap and subject with their interaction had an R² = 0.881 for both measurement points (B1 and C) in the supine position. Standard deviations of B1 and C were calculated for all observations for each wrap. Histograms for all observations for each wrap are presented for IP at B1 and C (Figures 1 and 2). As illustrated in Tables 9 and 10, post hoc analysis via Bartlett test for equal variances shows that the variances are statistically different for the measurements at B1 (P = .001) but not at C (P = .347).

The routine use of disposable, pre-packaged compression bandage sets is customary in the standard of care (SOC) management of VLUs and edema of the lower extremity. In addition, several of the ‘lite’ versions have also been referenced in the literature for the management of lymphedema in other areas including the arm, the chest wall, and genitals.⁵¹ The interchangeable use of generic descriptions of these compression bandage kits (ie, 2-layer, short stretch, elastic) that is pervasive in consensus statements,⁵² Cochrane reviews,¹^,⁸ clinical practice guidelines,^{4,10,20,21,42,53,54} and clinical studies documenting the efficacy of compression bandage kits^{1,7,35,47,55-79} disregards the unique technical characteristics of a specific compression bandage kit over another. Despite the rise in utilization of compression bandage kits across the continuum of care, in vivo comparative analysis of the IP and SSI of available compression textiles is lacking. Although in vitro dosage (IP) expected with proper application is provided by each manufacturer (Table 3), the reader should note that the dosage cited is relative to only IP at B1 and it does not clearly state if this dosage has been verified in vitro or in vivo. Clinicians that utilize compression should be aware that it has been cited that the laboratory performance of a bandage may not reflect its performance in clinical use.⁸ This statement is based on a well- referenced limitation that hemodynamic efficacy of a compression application is greatly influenced by application technique, amount of tension imparted on the textile, anatomical tissue variations, and underlying disease etiology.^{8,20,32,39,52} Furthermore, the dosage provided by the manufacturers only references the mmHg at the B1 location at the time of application.³² This information provides the clinician with no information regarding the dynamic performance of the textile combination(s), the SSI, the distribution of the dosage across (horizontal or vertical) the limb, nor the ability of the textile to maintain the stated ‘dosage’ over the treatment period.

The reader may be questioning as to why there is not more in vitro and in vivo data available for these compression applications that are a mainstay of treatment. The rationale is two fold. First, although there are standards for inelastic and elastic bandage material based on in vitro testing that can guide individual textile classification founded on degree of stretch required to achieve a sub-bandage pressure, these standards do not pertain to a combination of textiles in these packaged compression sets.⁴⁵ Unlike compression stockings for which there are standards that make it possible to identify the pressure exerted by the stocking and to define its class, there is not a universal standard that can estimate the dosage of a compression bandage set based on textile type alone.⁵⁹ Second, the sub-bandage pressure at the time of application and during a period of wear is influenced not just by bandage material but also the tension with which the material is applied, the number and pattern of application of layers, the radius of the limb, and the surface hardness of the tissue over which the compression is applied.^20,34,76,80 The latter of which can vary between patients as well as within a single patient depending on trophic changes, patient’s anatomy (limb shape/size), and functional activity level.

Comparative analysis of the observed IP and SSI measured at the time of initial application was statistically different between the 2-layer/2-component cohesive compression bandage kits. Prior to this study, there had been no comparative documentation of the compression properties of the compression bandage kits specifically to contest the pervasive assumption that 2-layer, or 2-component compression box sets are interchangeable as they are composed of the same number of components with a similar outer cohesive layer. Detailed in Table 3, each kit assessed as part of this study is composed of unique combinations of textiles. Although the specific composition (ie, % lycra, % cotton, laminated polyurethane foam) is available to a clinician via packaged inserts, the clinical implications of the formulations are not provided. The clinical impact (hemodynamic, biophysical) of the specific textile composition beyond IP is outside the scope of this study. Although most clinicians would have little to no use for knowledge of a specific textile composition, the elastic nature of each layer individually and as a combined unit in the form of the SSI would be relevant information. The SSI of a compression application has been cited as clinically relevant to the hemodynamic performance of any compression application, whether it be compression garments or bandages.^{48,64,72,81,82}

As none of the compression bandage kits assessed are composed of identical textiles, it was not entirely unexpected that the IP measurements recorded in the study would vary. However, statistical analysis of the observed ‘dosage’ post initial application showed that there was a statistically significant difference (P<0.05) relative to the IP measured at both B1 and C (Tables 5-7). As each boxed compression set was composed of the same number of layers/components, and applied in the same pattern in the area over the sensors (each are applied at 50% overlap with the exception of 1), these findings highlight the objective differences relative to individual textile composition. This conclusion should not be minimized. From these results, one could theorize that as they are composed of different textiles, with different physical properties (elasticity, stiffness), with statistically significant differences in IP and SSI, the clinical effectiveness may vary.

The objective findings of this research support conclusions of previous researchers who comparatively evaluated other packaged bandage sets. Dale et al⁴⁶ similarly studied 4 different packaged 4-layer compression bandage kits. In a similar design, the researchers documented that although each set was composed of similarly appearing textile components that were applied in a similar fashion, the observed IP was statistically different (P = .005).⁴⁶ Hafner et al⁸³ and Junger et al⁶⁵ observed similar differences amongst comparable 2-layer compression applications, concluding that the change in IP was dependent on composition of the layers not number of layers.⁸³

In addition to the differences in IP observed at B1 and C, the SSI at B1 was also observed to vary between compression bandage sets dividing the 7 compression box sets into 3 categories of SSI (Table 7). The SSI is the difference between the standing and supine resting pressures and has been documented as a "valuable parameter characterizing the efficacy of a specific compression product to narrow/occlude the venous lumen."⁴⁸ A high SSI equates to an intelligent bandage, allowing for more comfortable compression application due to a lower IP at rest in the supine position, and an increased IP in the upright position to counter the hemodynamic orthostatic pressure changes.⁴⁸ The variance in IP observed from the supine to the standing pressure results are due to a non-yielding, stiff material. It has been cited that the change in pressure exerts an intermittent massaging effect to the leg, thereby intermittently blocking venous reflux.⁸⁴ Mosti and Mattaliano reported a highly significant correlation between standing pressure and systolic pressure peaks during walking.⁷⁶

Other researchers have observed differences in SSI between the compression bandage kits and/or different combination of compression textiles. Hiria et al observed a difference in IP and SSI between various combinations and the order of application of compression textiles, citing a significant increase in the SSI when a short stretch bandage was applied over either short or long stretch bandages.³⁵ Wong et al observed differences in SSI and IP of 3 different 2-layer bandage systems utilized in Europe; however, the researcher did not comment on the statistical significance of the findings.⁷⁹ A stiffer bandage produces higher standing and working pressures even when starting from a relatively low resting pressure.⁷⁶

Based on the observed differences in IP and SSI between the boxed compression sets, one could hypothesize that there would be a difference in hemodynamic impact and clinical efficacy amongst the compression box sets. This is not to say that one compression application is superior to another. Instead, this study provides in vivo clinical evidence for the utilization of an alternative compression application if the desirable therapeutic outcome has not been achieved. As an example, if a wound was non-healing with product 2, a trial of products 1, 4, 5, or 7 whose IP and SSI were observed to be statistically higher, may improve the clinical outcome as the dynamic pressure provided should theoretically be different. Similarly, if a patient had been using product 1 and was unable to tolerate the compression due to reports of discomfort or feeling too tight, utilizing product 2, 3, or 6 may afford compression tolerance as the IP at rest was observed to be statistically lower.

Although the clinical impact of the variance in IP and SSI observed in this study was outside the scope of this study due to the small sample size and the single researcher, it has been documented that the effectiveness of a compression application is highly dependent on both an adequate IP^{9,20,21,27,77,84-87} and SSI.^{9,20,34,48,86,87} In the current study, statistical analysis revealed the variance of observed pressure was largely relative to the interaction of the bandage and the subject. Post hoc analysis on the variability of the observations of the B1 measurements in supine, but not the C measurements, show differences between standard deviations. As previously mentioned, the IP of an applied compression bandage set is not just relative to the textile but the interaction of the textile on tissue over which it has been applied. A variance in the shape, size, or tissue density that can be the result of trophic changes such as lipodermatosclerosis versus watery edema, could artificially increase or decrease the IP measured. This observation highlights the importance of not just looking at IP as the sole prescriptive characteristic, as IP and SSI vary independent of one another.^88,89

A final observation to be discussed is the absence of absolute pressure gradience relative to IP at B1 compared with C observed in this small data set of healthy subjects with ‘normal’ shaped lower extremities. As vertical gradience of IP was not the focus of this study, the author chose not to highlight this finding. Nonetheless, the reader should be aware that there is no definitive definition of what constitutes gradience (1 mmHg difference vs. 20 mmHg) for any compression application. Although the full discussion of this topic is outside the scope of this project, it is worth mentioning that the current dogma that assumes that compression applications are universally gradient and/or that a gradient profile is necessary to ensure therapeutic efficacy of a compression application is not fully supported by the literature.^{20,28,87,90-92} The initial rationale provided in support for a gradient compression application was based on theoretical compression pressure needed to reverse venous hypertension in the upright position. It had been stated that 40 mmHg at the ankle, with a graduated decrease up the leg to 20 mmHg at the calf, was neccessary.⁹³ Dogma within the compression field has blindly followed this mantra of the need for strong, gradient compression pressure at the ankle, despite conflicting published studies demonstrating that elastic stockings exerting 12 to 32 mmHg, as well as elastic kits exerting about 40 mmHg at the ankle were almost as effective as inelastic bandages or adjustable wraps applied with strong compression in reducing lower limb edema.^20,87 The need for gradience has been further challenged by Cuzan et al⁹⁴ and Mosti et al⁴¹ whose research demonstrated improved venous pumping function with higher pressure over the calf.

In the past, the therapeutic efficacy of compression has been measured on venous hemodynamics alone. The paradigm shift and expanding knowledge of the key role that the lymphatic system plays with regards to edema management as well as wound healing, heralds the need for a new line of inquiry including both the vascular and cellular impact of compression applications. There is a need to examine not just a compression application’s gradience in the vertical plane, but also the impact of the compression textile texture, and pressure distribution across the surface of the tissue capable of producing cellular deformation when applied as part of a compression application on the leg, or any other part of the body.

The authors acknowledge the primary limitation of this project was the narrow size of the project and the utilization of a small (n = 10) sample of convenience (healthy volunteers),and only a single clinician, which limits the generalizability of the findings. As such, the authors chose not to disclose the individual product names in the study as to not mislead the reader or the consumers relative to the compression products reviewed. The primary aim of the project was not to demonstrate that one product was superior but rather to objectively compare the products and the IP and SSI at the time of applications. The objective findings of a statistical difference between the products for the measured IP and SSI offers a theoretical explanation of the previous clinical observations by the authors of varying performance between products and patients. The observations gathered in this research study provide a foundation of how these compression box sets behave on healthy individuals, providing a baseline, and establishing the need for additional research projects inclusive of subjects with various disease states and tissue impairments.

The authors firmly asserts that compression selection should be more about matching the compression product to the patient presentation, contributing etiologies, and treatment goals. Compression selection should be driven by efficacy, not cost of a particular product. However, an evidence-based approach to meet this goal can only be achieved with additional research endeavors incorporating a larger sample size, and multiple clinicians applying the compression wraps. Furthermore, there is a need for researchers to document a comprehensive compression profile (IP, SSI, and compression distribution) of the products being utilized throughout the duration of a research study. This would allow for generalization of study outcomes based on objective findings rather than generic categorization (ie, – 2-layer or short stretch) of compression products.

A second limitation is the primary researcher's practical experience with each of the compression box sets reviewed. The researcher acknowledges that she had the most experience with products 2, 3, 5, and 7, and the least experience with product 1. Familiarity with a particular textile can have an impact on a clinician’s effective application/utilization of the compression product.⁹⁵ The reseacher acknowledges that she had the least experience with the product with the highest observed IP readings demonstrated in this study. The authors noted that this product’s second layer was subjectively stiffer and thicker compared with the other systems. It has been documented that bandage thickness can have an impact on IP.⁹⁶ In addition, the researcher observed that some of the products, other unique textile characteristics including amount of stretch of individual layers, presence/absence of visual indicators, and degree of the cohesive properties of the second layer (subjective amount of force required to unroll), varied amongst even those textiles that were similar in appearance. Efficacy and/or patient comfort is not assumed from these subjective or objective observations.

This second limitation could have been addressed with additional ‘in-person’ training by the manufacturer’s clinical specialists for each of the products reviewed, and/or the use of a pressure monitor to improve accuracy with compression application.^95,97,98 However, the primary researcher felt it was necessary to replicate ‘real-world’ experience. The authors acknowledge that not every clinician utilizing compression will have access to a live ‘trainer’ or an IP measurement device to assess application pressures.

A final acknowledged limitation was that the observed IP measurements were only taken at the time of initial application for each of the compression box sets assessed, limiting the full assessment of the dynamic compression profile of the compression box sets. Across all of the compression applications studied, the initial readings observed at the time of application were higher than expected by the primary investigator and higher than presented in the manufacturer’s information, for those that provided a specific dosage measurement. It has been document that the use of the PicoPress   point pressures readings recorded at individual locations around the circumference may vary dramatically, calling into question the value of sub-bandage pressure measuring devices for this application.⁶³ Ideally, the IP and SSI should have been serially measured over a period of time.

Multiple researchers have documented the reduction of IP, in both healthy volunteers and patients with venous disease, following application of a compression bandage.^{62,65,67,79,85,88,89} Stansal et al noted a significantly reduction in IP (P < .001) within the first 10 minutes after application of a 2-component short stretch bandage system.⁶² Mosti and Partsch observed that the mean pressure loss under an inelastic bandage, initially applied with a observed resting pressure of 64.5 mmHg (IQR 51-80 mmHg), was reduced by 54% in supine, and 35.4% in standing after 1-week of wear.⁸⁸ Interestingly, the researchers observed that although the IP reduced substantially over the 1 week period of observation, the SSI remined substantially unchanged.⁸⁸ Ning et al also documented a reduction in IP over a period of wear.⁸⁵ This group of researchers noted the temporal reduction in IP varied across the compression bandage applications studied regardless of the textile composition.⁸⁵ As the ability of a compression bandage application to maintain a ‘therapeutic’ dosage over the period of wear would speak to the hemodynamic efficacy, initial IP may not be as important as the change in IP over time. Additional work to investigate the change in IP and SSI over time for each of these products is warranted.

Despite the dogma in the profession of ‘dosage’ as the sole determinant of hemodynamic efficacy, the definition of ‘therapeutic dosage’ of a compression application will vary based on underlying etiology and patient presentation.^20,32 Therapeutic compression prescription requires both an understanding of the underlying etiology necessitating the need for compression, as well as the tissue characteristics and morphology (anatomical architecture) of the patient’s extremity. At a minimum, therapeutic compression prescription should include knowledge of IP and static stiffness of the compression bandage sets available. This will enable a clinician to better select a compression textile or product based upon the patient’s individual needs.

The observed differences between bandaging systems are potentially important in that they may give rise to differences in both benefits and risks according to patient presentation and underlying etiology. Furthermore, there are educational implications, elevating the conversation of compression beyond the number of layers of an application and beyond dosage.

Future research of compression applications should include documentation of the comprehensive compression profile of IP at the time of application and during the period of wear, the SSI and the distribution of the pressure across the tissue in both the vertical and horizontal planes. This would contribute to the understanding of not just how compression effects or impacts the vascular system, but the impact the textiles may have on tissue and cellular deformation and remodeling.

¹PhD candidate at Nova Southeastern University, Department of Physical Therapy, Dr. Pallavi Patel College of Health Care Sciences

²Sr. Quality Assurance Engineer, Ascend Performance Materials

³Professor, Nova Southeastern University, Department of Physical Therapy, Dr. Pallavi Patel College of Health Care Sciences

Suzie Ehmann, PT DPT PhD(c) CWS CLWT CLT-LANA, 319 53rd Ave North, North Myrtle Beach, SC  29582, Suzanne.ehmann@gmail.com