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Peer Review

Peer Reviewed

Consensus Statements

A Synthetic Hybrid-scale Fiber Matrix for Complex Surgical Wounds: Consensus Guidelines

May 2023
1943-2704
Wounds. 2023;35(5):E160-E168. doi:10.25270/wnds/22067

Abstract

Based on their own clinical experience and review of the available peer-reviewed data, the authors developed a consensus opinion on the use of an SHSFM for open wounds. The matrix has features such as varying pore sizes and fibers (ie, hybrid-scale) and is indicated for the treatment of open wounds. This report describes the design and utility of the SHSFM, its mechanism of action, and the methods of application, as well as clinical outcomes. The authors discuss their own experience and review of the published literature, then describe their protocols and rationale for the use of the SHSFM. These consensus statements include recommendations regarding appropriate wounds for use of the SHSFM, use of other wound therapies in conjunction with the SHSFM, reapplication rates, preparation methods, and additional discussions of appropriate use. This report is not a literature review, but rather is a statement of preliminary clinical experience. The consensus statements indicate that the SHSFM may be used to treat a variety of wounds and can be used to stage wounds to closure via skin grafts or by secondary intention.

Abbreviations

DFU, diabetic foot ulcer; FDA, United States Food and Drug Administration; MRSA, methicillin-resistant Staphylococcus aureus; NPWT, negative pressure wound therapy; SHSFM, synthetic hybrid-scale fiber matrix; STSG, split-thickness skin graft; TMA, transmetatarsal amputation; VLU, venous leg ulcer.

Introduction

Successful management of open wounds in the surgical setting is important for achieving wound closure and wound healing, and for minimizing complications such as infection.1 Complex, open wounds are those that are chronic in nature or that occur in patients with comorbidities that negatively affect wound healing.2 These wounds are at high risk for complications. The reconstructive ladder for treating wounds and soft tissue defects consists of management modalities of increasing complexity, from healing by secondary intention or primary closure to skin grafting and tissue transfer (eg, flaps).3 Several types of reconstructive therapies exist, including time-tested options such as skin grafts and flaps, and newer technologies such as biologic regenerative tissue products.4,5

Skin grafts have been used for millennia and include STSGs and full-thickness skin grafts.4 The grafts, which are removed from a donor site and transferred to the wound site, require a well-vascularized wound bed for graft survival.4,6 Skin flaps are categorized by their vascular supply and, for instance, may remain attached to their donor site blood vessels.6,7

While grafts and flaps have the potential for full integration into the wound bed owing to their autologous nature, they have inherent limitations concerning available donor size and donor site morbidity.4 The use of biologic regenerative tissues, including allografts and xenografts, can be challenging for providers and health care systems owing to the need for tissue tracking and storage.8 The July 2020 FDA guidance document on regulatory considerations for cellular and tissue-based products introduced new challenges, such as updated processes for these products to meet FDA requirements, which may limit access.8

Advanced solution using a SHSFM

Given the challenges associated with conventional wound therapies, an advanced intervention for the effective treatment of open wounds is needed. Bioengineered skin equivalents may offer a new solution by providing the therapeutic benefits of real skin in nearly unlimited quantities while avoiding undesired immune responses.4,9 Specifically, a biodegradable, fully SHSFM (Restrata; Acera Surgical, Inc) may be able to address unmet needs in the surgical management of wounds.

The SHSFM combines the advantages of synthetic construction with the positive attributes of biologic materials. This construction allows for controlled degradation of the matrix, resistance to enzymatic degradation, and biocomplexity as a synthetic, while also incorporating biomimetics similar to that of human extracellular matrix, fibrous architecture to support cellular proliferation, and porosity to encourage tissue ingrowth and vascularization as seen in biologics.10

The SHSFM is composed of polyglactin 910 and polydioxanone, both of which are well-studied, biocompatible, synthetic polymers used in other FDA-cleared devices, such as resorbable sutures.10 The polymers are co-electrospun into soft, white, compliant, nonwoven sheets that have a fibrous, highly porous structure with varying fiber diameters, with a range of fiber and pore sizes (ie, hybrid-scale fiber technology) that have been shown to be well-suited for fibroblast ingrowth and proliferation, collagen upregulation, neovascularization, and prevention of bacterial penetration11 (Figure 1). The pore sizes within the matrix are engineered to be between 5 µm and 500 µm in diameter, which is ideal for encouraging fibroblast migration, proliferation, and neovascularization.10 The matrix is composed of synthetic fibers, with an average fiber diameter less than 2000 nm. This structure mimics that of native human extracellular matrix, which is composed of collagen fibers that range in diameter between 50 nm and 500 nm. This architecture encourages cellular infiltration and retention, formation of new tissue, and neovascularization, with a tensile strength similar to that of skin.10 This process mimics the body’s natural wound healing process, and, by encouraging cellular proliferation, assists in progressing the wound from the inflammatory phase to the proliferative phase, in which granulation tissue forms over the wound and reepithelialization occurs.12

Figure 1

The SHSFM is resorbed over the course of a few weeks, at a rate designed to match the rate of new tissue formation and wound healing.10,13 The matrix is fully resorbable; thus, it does not require removal. The material is durable, can be stored at room temperature, and has a 2-year shelf life; it can be cut to size; it can be meshed and secured using sutures, surgical adhesive strips, or staples; and it resists enzymatic degradation.10

Given its engineered properties and demonstrated benefits, the SHSFM may be beneficial for use in the surgical reconstruction of open wounds. The matrix may be an option as an adjunctive therapy to skin grafts and skin flaps, including site preparation for staged procedures to promote granulation at the wound bed, as a supplement for coverage of large surface areas where skin grafts and flaps may not be sufficient, and for high-risk donor sites. The SHSFM may also be an option as a primary alternative to skin grafts and flaps, including for sites where grafts or flaps are not successful and for high-risk patients.

 

Preclinical data

MacEwan et al13 assessed the SHSFM in a porcine wound model. Full-thickness wounds 3 cm in diameter were created along the dorsum between the shoulder and ilium and were extended down to the fascia. The wounds were treated with either the synthetic matrix or a bilayer xenograft matrix (Integra Bilayer Matrix Wound Dressing; Integra LifeSciences). Wounds were grossly observed for up to 30 days after application to evaluate wound healing, and tissue samples were collected at 2 and 4 weeks and stained using hematoxylin-eosin for histopathologic assessment (Figure 2). Healing was 2 times faster with the SHSFM than with the bilayer matrix, as measured through faster rates of granulation tissue formation, collagen deposition, vascularization, and wound closure; reduced inflammation; and more complete reepithelialization.

Figure 2

The findings of that animal model suggest potential clinical benefits of surgical applications of the SHSFM, such as faster time to STSG or flap reconstruction.

 

Literature review of the SHSFM for open wounds

Since receiving FDA clearance and being made commercially available for use in humans in 2017,14 the SHSFM has been used in conjunction with various surgical strategies to manage wounds, ranging from secondary intention and primary/delayed primary closure (ie, primary closure at time of surgical procedure and primary closure at a later date) to augmentation of grafts and flaps. Encouraging outcomes have been described in published level III and IV studies.

In a study of healing by secondary intention, Fernandez et al15 evaluated the use of the SHSFM in place of STSG to treat 3 open wounds, resulting from calciphylaxis, an abdominal fistula, and necrotizing fasciitis of the hand and arm. The patient with calciphylaxis was a high-risk case who was not well-suited to STSG owing to possible cutaneous complications associated with calciphylaxis. The patient with abdominal fistula developed a mid-jejunal enteroatmospheric fistula with an output of 1000 mL per day that was unsuccessfully managed with a STSG and NPWT (the small intestinal succus dissolved the STSG). In the patient with necrotizing fasciitis, exposed tendons precluded the use of STSG. In all cases, the synthetic matrix was fenestrated and used in conjunction with NPWT as needed until sufficient healing was observed. Treatment following use of the SHSFM resulted in significant healing in all cases.15

Treatment by primary/delayed primary closure was investigated by Alexander et al16 in a prospective study in which 10 patients who underwent TMA were treated with augmented closure utilizing the SHSFM (experimental group) were compared with 10 patients who underwent TMA with standard primary closure (control group). In the experimental group, the SHSFM was placed in the wound bed to encourage granulation tissue formation, the wound was closed using sutures, and another strip of the synthetic matrix was then secured on the suture line to ensure lasting wound closure and avoid wound dehiscence. Augmented closure led to an improved limb salvage rate (20% limb loss in the treatment group vs 40% limb loss in the control group), a higher healing rate, shorter time to healing, and a reduced complication rate compared with control treatment.16

Use of the SHSFM for augmentation of an STSG was described in a case study by Martini et al.17 In a patient with a traumatic crush injury, the SHSFM was applied to the wound bed to encourage granulation tissue formation prior to application of an STSG. Three weeks after application of the SHSFM, the wound bed was well-granulated and ready for application of the STSG, and 3 weeks after application of the STSG, 100% take of the STSG was observed. No complications were reported.

Vallery and Shannon18 evaluated the clinical efficacy of the SHSFM to prepare the wound bed for flap reconstruction. Eleven patients with stage 3 or 4 pressure ulcers were treated with the synthetic matrix to encourage granulation tissue formation prior to flap reconstruction. Follow-up was conducted up to 165 days after flap reconstruction. Complete wound closure was achieved in 10 patients, and 1 patient achieved 97.2% wound area reduction, for an overall wound closure rate of 90.9%. No complications were reported.

Post-Mohs surgical wounds have also demonstrated reepithelialization after treatment with the SHSFM. In a single-arm retrospective clinical study at a single site, 4 patients with nonmelanoma skin cancers on the auricular helix underwent Mohs micrographic surgery.19 Negative wound margins were confirmed, after which the SHSFM was applied to the wound bed. After an average of 1.25 applications to the wound bed, all wounds fully reepithelialized in 7.9 weeks with minimal scar formation.

Several other recent publications have investigated the clinical efficacy of the SHSFM in the management of lower extremity wounds in a nonsurgical, outpatient setting. These include a prospective clinical study of 24 patients demonstrating closure of 75% of DFUs20 and a retrospective study of 23 lower extremity wounds demonstrating 100% closure of TMAs, 100% closure of VLUs, and 75% closure of DFUs.21 The SHSFM has also shown promising results in the management of lower extremity hematomas, as demonstrated in a retrospective review of 2 hematomas treated with the matrix until complete reepithelialization.22

The SHSFM has shown efficacy in case studies investigating its use in chronic wounds. In a case study of 4 chronic neuropathic ulcers, application of the SHSFM resulted in granulation tissue formation and decreased wound area in all cases.23 Chronic DFUs and VLUs have been successfully treated with the SHSFM. In a study of 23 DFUs and VLUs with an average wound age of 16 months, 96% of wounds demonstrated complete closure after treatment with the SHSFM.24 In a different study of chronic DFUs, VLUs, and other wounds, 82 wounds that had remained open for at least 4 weeks were treated with the SHSFM; an 85% complete closure rate was achieved.25 In addition to DFUs, VLUs, and other lower extremity wounds, pressure ulcers have been treated with the SHSFM. A 16-year-old pressure ulcer that persisted despite NPWT and multiple skin flap procedures demonstrated successful tissue granulation and formation of new epithelium after application of the SHSFM.26

Clinical results show positive healing outcomes with the SHSFM (Figure 3).

Figure 3

 

Clinical advisory panel consensus recommendations

The authors developed this consensus document to better guide the use of the SHSFM in the management of open wounds. The purpose of this document is to develop a best practice, evidence-based guideline for clinicians (including trauma, plastic, general, podiatric, vascular, and head and neck reconstruction surgeons) regarding the clinical application settings and protocols for the use of the SHSFM in open wounds. A summary of the published evidence and expert clinical recommendations are included in this report.

The authors developed several consensus opinions, based on their clinical experience and review of the available peer-reviewed data. The expert clinical panel members were selected by the primary author based on their clinical experience with the SHSFM after a discussion of the technology at the 2021 Symposium on Advanced Wound Care in Las Vegas, Nevada (October 29-31, 2021).

Methods

The panel members reviewed the biochemistry of, biomechanics of, use indications for, and published results on the SHSFM, as well as their own clinical experience with the product. Given the novel technology of the SHSFM, the panel determined that consensus guidelines should be created to address the various uses of the matrix and how to achieve optimal results. Prior peer-reviewed publications have addressed specific use cases for the SHSFM; however, a document outlining all use options for the SHSFM has been lacking.

The panel discussed their own experiences and best practices with the SHSFM and reviewed the available peer-reviewed publications on the SHSFM, then developed and drafted consensus statements based on these findings. The consensus statements are based on the authors’ clinical experience as well as peer-reviewed articles on early clinical use of the SHSFM. This article is not primarily intended as a literature review.

Results

This consensus document was developed with existing and evolving clinical data available as of this writing (Table). As new data become available, the consensus will be modified as needed.

Table

 

Consensus Statement 1: In conjunction with appropriate wound care, such as debridement and primary/secondary dressing changes, the SHSFM may be used as an adjunct therapy for the treatment of open wounds, either for complete reepithelialization and wound closure or as a dermal bridge.

The SHSFM has tensile strength for surgical applications and can be applied in a way that addresses the clinical outcome goals for each wound. It can be used in wound care and can enable complete reepithelialization of the wound bed and wound closure, or it can be used as a dermal bridge, such as for flaps, grafts, and donor sites to reduce pain.15-26

In a prospective clinical study, the SHSFM was used to treat 24 DFUs, 75% of which achieved complete reepithelialization and wound closure within 12 weeks of treatment with the synthetic matrix.20 The SHSFM was used to achieve complete reepithelialization in post-Mohs surgical wounds as well; McGowan19 applied the matrix to 4 post-Mohs wounds on the ear, and all achieved closure in 7.9 weeks. Martini et al17 successfully used the SHSFM as a dermal bridge to an STSG, which was applied 3 weeks after matrix application and successful granulation of the wound bed.17

The SHSFM can be used to achieve clinical goals of patients and providers alike. Acute and smaller wounds typically can be treated with the SHSFM alone until complete reepithelialization.19-20,22 For large or chronic wounds, however, the SHSFM may be used to prepare the wound bed for an STSG or flap reconstruction.18,22 Especially in deep wounds, the goal of treatment with the SHSFM may be to fill in the wound with healthy, granular tissue in preparation for a graft or flap.18,26 Importantly, the SHSFM has demonstrated rapid granulation of wounds and over exposed structures and can be used synergistically with other wound products.15,18,20 Such use is further discussed in consensus statements that follow.

 

Consensus Statement 2: The SHSFM may be used in the following wounds: (a) traumatic wounds, (b) dehisced wounds, (c) pressure injuries/ulcers, (d) wounds with exposed underlying structure (eg, bone, tendon), (e) partial-thickness burns after excision, (f) wounds resulting from evacuation of a hematoma after hemostasis is achieved, (g) wounds that are a bridge to STSG coverage or closure via tissue flaps, and (h) wounds that are a bridge between staged or delayed amputation.

The SHSFM can be used on a variety of difficult-to-heal wounds. The varying fiber diameters and porosity of the matrix allow for cellular infiltration, neovascularization, and new tissue formation.

The SHSFM was used in a preliminary case series of 3 patients to treat traumatic injuries, including calciphylaxis, cellulitis, and an abdominal trauma wound with success, even when the SHSFM was exposed to bile.15 In a retrospective case study of 2 patients with hematoma, the SHSFM was applied to the wound bed after evacuation, and both wounds were fully reepithelialized on an average of 11 weeks after initial application.22

The SHSFM can also be used in the management of ulcers. Studies of DFUs20 and VLUs25 have demonstrated 12-week healing rates of 75% in 24 patients and 91% in 34 patients, respectively. Pressure ulcers have also responded well to treatment with the SHSFM, as demonstrated by a case series of 11 patients in which the matrix was used to prepare the wound bed for a flap reconstruction, resulting in a wound closure rate of 90.9%.18 In the case of a pressure ulcer for which prior advanced treatments were unsuccessful, significant granulation of the wound bed—including granulation tissue formation over exposed vertebrae—was achieved after 9 applications of the SHSFM.26 TMAs have also shown improved healing when the SHSFM has been introduced into a treatment paradigm. In a prospective case series of 20 patients in which 10 received the SHSFM and 10 received standard primary closure after TMA, placement of the SHSFM in the wound bed prior to closing the amputation wound and reapplication of it over the suture line resulted in an 80% wound healing rates versus 60% for control.16

The existing literature and the authors’ experience indicate that the SHSFM shows promising results in the treatment of open wounds.
 

Consensus Statement 3: The SHSFM can be used in conjunction with other advanced wound therapies. Compatible dressings and solutions include (a) normal saline, (b) hypochlorous acid solution, (c) sodium hypochlorite solution (dilute Dakin solution 0.125% [quarter strength]), (d) hydrogel, (e) petrolatum gauze, (f) nonadherent dressings, (g) absorptive dressings, (h) ointments, and (i) antibiotic solutions. Compatible advanced therapies include NPWT.

Nonadherent dressings are commonly used over the SHSFM as the primary dressing.20,23,25 The SHSFM can also be used in conjunction with other dressings and solutions, such as saline, petrolatum-based gauze,21 and antibiotic dressings.15 The SHSFM has been successfully used in conjunction with NPWT in the management of venous ulcers, DFUs, TMA wounds, skin lesions owing to calciphylaxis, abdominal fistula, necrotizing fasciitis, hematomas, and pressure ulcers.15,18,21,23

When using NPWT in conjunction with the SHSFM, the authors of this consensus document begin by irrigating the wound with instillation fluid.15 Typically, following previous literature, the authors then apply the SHSFM to the wound bed and secure it with staples, sutures, or adhesive strips. Next, a nonadherent dressing is applied, and the NPWT dressing is placed and initiated. Typically, standard NPWT is applied at a pressure of −85 mm Hg, −100 mm Hg, or −125 mm Hg, with dressing changes occurring at 3- to 5-day intervals up to 7 to 10 days after initial application.15,18,21,22

 

Consensus Statement 4: The SHSFM may be used in (a) wounds with exposed tendons, ligaments, bone, and nerves; (b) wounds with explored tunnels; and (c) wounds with explored areas of undermining.

The available clinical data show that the SHSFM has been applied to wounds with exposed structures and has supported wound healing and reepithelialization. The authors of the current manuscript previously reported on the management of a necrotizing fasciitis wound of the hand with exposed tendon.15 That patient first underwent repeat incision and drainage and surgical debridement to manage an infection. Once the infection was resolved, the SHSFM was applied to the wound with exposed tendon. Significant epithelial coverage of the wound was achieved 7.5 weeks after treatment with the SHSFM.

In a case series, Abicht and Barton21 reported on a patient with an infected refractory DFU for which partial foot amputation was unsuccessful. The patient underwent TMA and received antibiotics for infection management. Following the amputation, the SHSFM was used over the exposed tendon in the residual metatarsals prior to flap closure. Wound assessment 6 weeks postoperatively showed complete healing of the TMA and no sign of wound dehiscence.

 

Consensus Statement 5: In conjunction with appropriate wound care, such as debridement and systemic antibiotics, the SHSFM may be considered for use in wounds with the following characteristics: (a) adequately cleansed and debrided wounds, (b) clean wounds, (c) contaminated wounds, (d) wounds with heavy bioburden, (e) colonized wounds, and (f) wounds in which granulation is difficult to achieve.

Studies have shown that the monomers and degradation products of polyglactin have antimicrobial effects.10 Furthermore, the initial pore size of the nonwoven electrospun scaffold is in the range proven to prevent bacterial penetration.10 The fully resorbable construction of the SHSFM also suggests that the matrix can be cleared without the risk of biofilm formation. Unlike collagen-based biologic materials, the SHSFM is resistant to bacteria in the wound bed.10 It has been demonstrated that pH plays an important role in wound healing. Many chronic wounds have a pH between 7.5 and 9, a range conductive to bacterial growth.30 A mildly acidic environment has been shown to encourage wound healing, and the SHSFM has been shown to elicit a mildly acidic environment in vitro29 (Figure 4).

Figure 4

Peer-reviewed clinical data indicate that the SHSFM can be applied to colonized and contaminated wounds while supporting wound healing and reepithelialization, and that the matrix is suited for use in colonized wounds.15,20,23,25,27-29 Fernandez et al15 reported on a patient with a contaminated wound who underwent incision and drainage of the dorsal hand, volar forearm, and medial-lateral forearm. After repeat incision and drainage, washout, and application of the SHSFM with NPWT, wound healing was seen at 7.5 weeks after treatment. Success in the management of contaminated wounds has also been demonstrated. Quintero et al29 used the SHSFM in the management of an abscess infected with community-acquired MRSA. The abscess was treated with incision and drainage, and 22 days later the wound was cleansed, irrigated with antiseptic solution, and debrided. The wound was then treated with the SHSFM, and complete closure was achieved 31 days after initial application. Longobardi27 used the SHSFM in a patient with a DFU that was not responding to clindamycin antibiotics and collagenase ointment. The wound was surgically debrided, and the SHSFM was fenestrated and placed in the wound bed using staples. Ten weeks after the initial application, the wound was completely healed.

In the clinical setting, the SHSFM has been shown to promote healing in contaminated and colonized wounds, formation of granulation tissue, and successful treatment in conjunction with systemic antibiotics. As a synthetic, the SHSFM is less susceptible than biologic materials to bacterial degradation and therefore can be used in contaminated wounds; however, the matrix should not be used in actively infected wounds.

 

Consensus Statement 6: Appropriate methods for preparing the SHSFM for application to a wound bed include (a) fenestration, (b) meshing, (c) cutting to fit the size of the wound, and (d) soaking in sterile isotonic solution.

The SHSFM is simple and easy to use. Complete details can be found in the instructions for use for the matrix.31 The following are tips for use based on clinical experience with the material.

The material can be fenestrated with a scalpel or meshed using a surgical mesher.15,18,19,21-24 If a surgical mesher is used, the mesh ratios will vary depending on the amount of coverage desired. The authors of the current manuscript routinely use a ratio of 2 to 1 or 3 to 1 when meshing the SHSFM.15 The product is also supplied in pre-meshed sheets with an expansion rate of approximately 2 to 1. The matrix can be manually cut to size to provide adequate wound coverage.15,21 In the experience of the authors of these guidelines, cutting to size is best done while the material is dry. The authors recommend soaking the SHSFM, particularly if the anatomic topography of the local wound is complex, to allow for better contact between the matrix and the wound and compliance in the wound, as well as to assist in initial material wound adherence.15,19 The authors commonly use a 2- to 3-minute soak while preparing the wound. Some physicians soak the matrix for up to 10 minutes.19 No special monitoring is needed during the soak period.

 

Consensus Statement 7: Appropriate methods for securing the SHSFM to a wound bed include (a) suturing using non-resorbable suture material, (b) suturing using resorbable suture material, (c) stapling, (d) adhesive surgical tape, (e) bolster dressing, (f) NPWT, and (g) applying an overlying nonadherent primary dressing.

The SHSFM can be secured using the physician’s preferred fixation method.3 Given the resorbable nature of the SHSFM, it is recommended to use an absorbable method of fixation, such as absorbable sutures, tissue sealant, or dissolvable clips.31 However, this is not essential, and other methods will work. For instance, in cases in which NPWT is also applied, the SHSFM can be fixed to the wound using nonadherent dressings and the NPWT dressing system. In the management of lower extremity wounds, Barton and Abicht21 used sutures or butterfly bandages to secure the SHSFM to the wound bed, Abicht et al20 used sutures or adhesive strips as necessary, and Husain et al24 used sutures. In TMA and flap reconstruction of pressure ulcers, the SHSFM was placed in the deep void under the closed flaps to support granulation tissue formation and avoid wound dehiscence.16,18 In addition, in the TMA study a thin strip of the SHSFM was secured on the suture line using a suture or staple.16 For dry wounds, some physicians hydrate the SHSFM with normal saline for 5 to 20 minutes and apply hydrogel directly onto the material.19,28 Soft silicone dressings over the wound and matrix have also been used; these dressings remained in place between office visits.28

 

Consensus Statement 8: Appropriate reapplication rates of SHSFM to a wound bed include (a) weekly reapplication in wounds with heavy exudate, (b) biweekly reapplication in wounds with moderate exudate, (c) single-use application in wounds for staging to definitive closure such as with STSG or flap reconstruction, and (d) more applications of the SHSFM in deep wounds versus superficial wounds to fully fill the wound and achieve reepithelialization.

The SHSFM can be reapplied as needed, based on clinician discretion, type of wound, and clinical goal.31 In a case series of traumatic wounds, the SHSFM was reapplied on a weekly basis for 5 weeks for lesions associated with calciphylaxis, was applied 4 times over 6 weeks for a lesion related to an abdominal fistula, and was applied once for lesions related to necrotizing fasciitis.15 In all cases, application of the SHSFM in conjunction with NPWT resulted in significant wound healing across all 3 wound etiologies.15

Herron26 reported success with multiple applications of the matrix in deep wounds with heavy exudate. A pressure ulcer measuring 5 cm deep and with significant exudate was treated with 9 applications over 11 weeks, at the end of which time 2 cm of epithelium had formed at the wound site and exudate had decreased by 50%.

In wounds being prepared for STSG or flap reconstruction, success has been achieved following a single application of the SHSFM. The SHSFM was used in a case series of 11 pressure ulcers to prepare the wound bed for flap reconstruction, resulting in a higher rate of successful flap take compared with the standard of care.18 In a case series of patients who underwent TMA, the matrix was applied to the wound bed at the time of surgery, which resulted in an improved healing rate compared with the control group.16 The SHSFM can also be used to promote granulation formation over a wound bed prior to STSG as demonstrated by Martini et al.17 For DFUs, VLUs, and other lower extremity wounds, the SHSFM has been used either weekly or biweekly at the physician’s discretion, resulting in healing rates of 75% to 91% at 12 weeks.20,25 Killeen et al23 used the matrix on a biweekly basis for chronic wounds. Other investigators used the matrix less frequently, applying it only once in 87% of patients and achieving 96% complete healing at 13.6 weeks.21

 

Consensus Statement 9: The SHSFM may be discontinued when (a) clinical goals are met; (b) the wound demonstrates complete reepithelialization; (c) the wound is deemed ready for surgical closure or coverage via STSG, flap, or another means; and (d) the wound is clinically stable for application of other standard advanced therapy.

The SHSFM can be used to achieve a variety of different clinical goals depending on physician discretion and the course of care. Such goals may include full wound closure, or wound preparation for another treatment course. Several clinicians have demonstrated how they use the SHSFM to meet the specific needs and treatment plan of their patients.

In a case study of 82 chronic wounds, the SHSFM was used to achieve full closure, resulting in complete closure in 85% of all wounds.25 This approach has been used by other physicians as well, resulting in chronic wound total healing rates of 75% to 96%.20-21,24 In the case of a chronic pressure ulcer, the clinical goal was to manage the wound sufficiently to discharge the patient from the hospital; this goal was achieved after 9 applications of the matrix and the formation of new epithelium at the wound site.26 Clinical goals were also met in a case series in which 4 chronic wounds achieved significant granulation tissue formation and the affected limb was salvaged.23 In addition, the SHSFM can be used to prepare for flap reconstruction or skin grafts, or to mitigate the risk of dehiscence and improve healing outcomes in amputation wounds.15,16,18

 

Consensus Statement 10: The SHSFM is not recommended in (a) actively infected wounds; (b) wounds with the presence of exposed, unprotected organs and vessels; (c) wounds with the presence of undrained abscess(es); (d) wounds with necrotic tissue; (e) acutely ischemic wounds; or (f) patients with known allergy to resorbable suture materials.

Per the instructions for use, the SHSFM is contraindicated in patients with known sensitivity to resorbable suture materials.31 Prior to applying the matrix, wounds should be debrided to remove any nonviable or necrotic tissue to ensure wound edges contain viable tissue. Wounds should also be free of exudate, and any bleeding should be stopped prior to application. The wound should not be actively infected or necrotic.31

Discussion

The SHSFM represents a new technology in the field of acute and chronic wound care. Early clinical experience demonstrates that the product has potential in multiple areas. It has been used successfully in the operating room and in the outpatient setting for a wide range of applications. The data to date have shown high rates of closure with this product, either when combined with sequential grafting or when used to achieve closure by secondary intention.

The goal of convening this expert panel was to provide a framework for pursuing further clinical investigation. Further clinical data will be forthcoming from prospective randomized DFU trials and a prospective randomized VLU trial that are currently in process. An update on best clinical practice with this product is expected in the next 36 to 48 months, because there will be a significant increase in the clinical availability and use of the product.

Limitations

There are limitations associated with these consensus guidelines, including the limited size of the panel used to develop the guidelines. The data on which the consensus guidelines are based consist of author experience and level III and IV clinical data from peer-reviewed publications. However, the successful clinical use and benefits observed to date warrant further investigation to refine these guidelines. A large, randomized controlled trial should be considered to confirm the results seen in preliminary retrospective studies.

Conclusions

The SHSFM is fully synthetic and offers unique features and benefits in clinical practice, including clinical applications across sites of service, minimal host inflammatory response, and controlled resorption rate. The gradual resorption of the fibers supports cellular growth and neovascularization, and it allows for a controlled transition from the SHSFM to the formation of new tissue. The matrix can be applied at bedside or in the operating room, allowing for flexibility in treatment.

The SHSFM can be used to achieve the clinical goals for individual patients, whether full reepithelialization of the wound, preparation for a graft or flap, or granulation over exposed structures. A variety of dressings can be used in conjunction with the SHSFM, in addition to other advanced therapies, such as NPWT. Unlike biologic materials, the SHSFM is resistant to enzymatic degradation and bacteria in the wound bed and can be used in contaminated wounds in conjunction with proper antibiotic treatment. Observed healing rates of 75% to 100% and the variety of clinical applications make the SHSFM a novel solution for the management of open wounds.

Acknowledgments

Authors: Luis G. Fernandez, MD1; Marc R. Matthews, MD2; and Paul J. Kim, DPM3

Affiliations: 1The University of Texas Health Science Center, Tyler, TX; 2The Arizona Burn Center, Phoenix, AZ; 3University of Texas Southwestern, Dallas, TX

ORCID: Fernandez, 0000-0002-2730-0199; Matthews, 0000-0003-0832-0562; Kim, 0000-0002-6186-6890

Disclosure: Dr Fernandez is a paid consultant for Acera Surgical. The other authors have no relevant disclosures.

Correspondence: Luis G. Fernandez, MD; Professor of Surgery, UT Health East Texas Physicians Tyler - Trauma Surgery, 1020 E. Idel St., Tyler, TX 75701; thebigkahuna115@gmail.com

How Do I Cite This?

Fernandez LG, Matthews MR, Kim PJ. A synthetic hybrid-scale fiber matrix for complex surgical wounds: consensus guidelines. Wounds. 2023;35(5):E160-E168. doi:10.25270/wnds/22067

References

1. Ferreira MC, Tuma P Jr, Carvalho VF, Kamamoto, F. Complex wounds. Clinics (Sao Paulo). 2006;61(6):571-578. doi:10.1590/s1807-59322006000600014

2. Labib AM, Winters R. Complex wound management. [Updated 2022 Jul 1]. In: StatPearls [Internet]. StatPearls Publishing; January 2022.

3. Glat PM, Davenport T. Current techniques for burn reconstruction: Using dehydrated human amnion/chorion membrane allografts as an adjunctive treatment along the reconstructive ladder. Ann Plast Surg. 2017;78(2 Suppl 1): S14-S18. doi:10.1097/SAP.0000000000000980

4. Sun BK, Siprashvili Z, Khavari, PA. Advances in skin grafting and treatment of cutaneous wounds. Science. 2014;346(6212):941-945. doi:10.1126/science.1253836

5. Dai C, Shih S, Khachemoune A. Skin substitutes for acute and chronic wound healing: an updated review. J Dermatolog Treat. 2020;31(6):639-648. doi:10.1080/09546634.2018.1530443

6. Braza ME, Fahrenkopf MP. Split-thickness skin grafts. In: StatPearls [Internet]. StatPearls Publishing; 2022.

7. Lucas JB. The physiology and biomechanics of skin flaps. Facial Plast Surg Clin North Am. 2017;25(3):303-311. doi:10.1016/j.fsc.2017.03.003

8. U.S. Department of Health and Human Services Food and Drug Administration Center for Biologics Evaluation and Research, Center for Devices and Radiological Health, Office of Combination Products. (2020, July). Regulatory Considerations for Human Cells, Tissues, and Cellular and Tissue-Based Products: Minimal Manipulation and Homologous Use. https://www.fda.gov/media/109176/download

9. Przekora A. A concise review on tissue engineered artificial skin grafts for chronic wound treatment: can we reconstruct functional skin tissue in vitro? Cells. 2020;9(7):1622. doi:10.3390/cells9071622

10. MacEwan MR, MacEwan S, Kovacs TR, Batts J. What makes the optimal wound healing material? A review of current science and introduction of a synthetic nanofabricated wound care scaffold. Cureus. 2017;9(10):e1736. doi:10.7759/cureus.1736

11. Kumbar SG, Nukavarapu SP, James R, Nair LS, Laurencin, CT. Electrospun poly (lactic acid-co-glycolic acid) scaffolds for skin tissue engineering. Biomaterials. 2008;29(30):4100-4107. doi:10.1016/j.biomaterials.2008.06.028

12. Guillamat-Prats R. The role of MSC in wound healing, scarring and regeneration. Cells. 2021;10(7):1729. doi:10.3390/cells10071729

13. MacEwan MR, MacEwan S, Wright AP, Kovacs, TR, Batts J, Zhang, L. Comparison of a fully synthetic electrospun matrix to a bi-layered xenograft in healing full thickness cutaneous wounds in a porcine model. Cureus. 2017;9(8):E1614. doi:10.7759/cureus.1614

14. US Food and Drug Administration, Medical Devices. Restrata Premarket Notification. Cleared 26 April 2017. Retrieved 04 April 2023 from https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K170300

15. Fernandez L, Schar A, Matthews M, Kim PJ, Thompson C, Williams N, Stutsman M. Synthetic hybrids-scale fiber matrix in the trauma and acute care surgical practice. Wounds. 2021;33(9):237-244.

16. Alexander J, Desai V, Denden S, et al. Assessment of a novel augmented closure technique for surgical wounds associated with transmetatarsal amputation: a preliminary study. J Am Podiatr Med Assoc. 2022;112(5):20-256. doi:10.7547/20-256

17. Martini CJ, Burgess B, Ghodasra JH. Treatment of traumatic crush injury using a synthetic hybrid-scale fiber matrix in conjunction with split-thickness skin graft. Foot Ankle Surg (N Y). 2022;2(1):100112. doi:10.1016/j.fastrc.2021.100112

18. Vallery M, Shannon T. Augmented flap reconstruction of complex pressure ulcers using synthetic hybrid-scale fiber matrix. Wounds. 2022;33(1):1-10. doi:10.25270/wnds/121521.01

19. McGowan J. Reconstruction of post-Mohs surgical wound using a novel nanofiber matrix. Wounds. 2022;34(8):209-215. doi:10.25270/wnds/20150

20. Abicht B, Deitrick G, MacEwan MR, Jeng L. Evaluation of wound healing of diabetic foot ulcers in a prospective clinical trial using a synthetic hybrid-scale fiber matrix. Foot Ankle Surg (N Y). 2022;2(1):100135. doi:10.1016/j.fastrc.2021.100135

21. Barton EC, Abicht BP. Lower extremity wounds treated with a synthetic hybrid-scale fiber matrix. Foot Ankle Surg (N Y). 2021;1(3):100076. doi:10.1016/j.fastrc.2021.100076

22. Temple EW. Treatment of hematomas using a synthetic hybrid-scale fiber matrix. Cureus. 2022;14(7)e26491. doi:10.7759/cureus.26491

23. Killeen AL, Brock KM, Loya R, Honculada CS, Houston P, Walters JL. Fully synthetic bioengineered nanomedical scaffold in chronic neuropathic foot ulcers. Wounds. 2018;30(10):E98-E101.

24. Husain K, Malik A, Kirchens J. Treatment of complex lower extremity wounds utilizing synthetic hybrid-scale fiber matrix. J Am Podiatr Med Assoc. 2023;113(1):21-071. doi:10.7547/21-071

25. Regulski MJ, MacEwan MR. Implantable nanomedical scaffold facilitates healing of chronic lower extremity wounds. Wounds. 2018;30(8):E77-E80.

26. Herron K. Treatment of a complex pressure ulcer using a synthetic hybrid-scale fiber matrix. Cureus. 2021;13(4):e14515. doi:10.7759/cureus.14515

27. Longobardi, J. Treatment of a recalcitrant diabetic ulcer with a synthetic hybrid-scale fiber matrix. Poster presented at: Symposium on Advanced Wound Care; May 10-14, 2021; Virtual.

28. Madden N, Donnelly H. Synthetic hybrid-scale fiber matrix for the treatment of surgical wounds, Poster presented at: Symposium on Advanced Wound Care; November 4-6, 2020; Virtual.

29. Quintero DB, Hodge D, Dietsch F, Cortez G. Synthetic hybrid-scale fiber matrix in abscess with community acquired MRSA. Poster presented at: Symposium on Advanced Wound Care; October 29-31, 2021; Las Vegas, NV.

30. Restrata. Restrata and impact on pH. Acera Surgical Inc.; 2021. (Data on File).

31. Restrata. Restrata. Instructions for use. Acera Surgical Inc.; 2020.