Complex Skin Defects Research Articles

Treatment of full-layer skin defects using decellularized pig skin dermal matrix

The choice of treatment methods for complex skin defects poses certain technical and medical difficulties related to the choice of material for filling the wound defect and its antigenic compatibility. A promising direction in the treatment of skin defects is the use of decellularized (celluless) pig skin, the composition and structure of which is as close as possible to the patient's dermis.
 The aim of the study was to analyze the clinical case of a patient with a basal cell carcinoma in the right wing of the nose, who was treated with full-layer skin defects using a decellularized dermal matrix from pig skin.
 Material and methods of investigation. Patient P., 94 years old, with a basal cell carcinoma in the area of the right wing of the nose, underwent treatment. As a material applied directly to the wound, a flap of acellular dermal matrix (ADM) of pig skin with preservation of the native structure was used.
 Results. 6 weeks before the visit to the dermatologist, the patient developed a pea-sized papule on the skin in the area of ​​the wing of the nose, which increased in size and became painful on palpation. When examining the skin in the area of ​​the right wing of the nose, a tumor-like formation was observed, 1x1 cm in size, flesh-colored, with peeling on the surface and vascularization, firm consistency, painful. Regional lymph nodes are not enlarged. The formation is clearly separated from healthy skin. The oncologist made a diagnosis: basal cell carcinoma. The tumor was removed, resulting in a full-layer skin defect measuring 1x1.5 cm with connection to the nasal cavity. Acellular dermal matrix was used to close the defect on the 3rd day after surgery. The flap was placed so that it did not cover the skin around the wound. With the help of "Levomykol" ointment, a moist chamber was created over the dermal flap. The dressing was changed every 2-3 days. On the 14th day, the flap peeled off, a granulating wound with signs of marked marginal epithelization formed in its place. The bottom of the wound was located almost at the same level as the intact skin. On the 21st and 26th day, active marginal epithelization of the wound and wound healing under the scab were noted. The bandage was not used during this period. On the 32nd day, the wound closed.
 Conclusions. Decellularized dermal matrix of pig skin when closing a full-layer postoperative skin defect creates optimal conditions for reparative wound regeneration. The effectiveness of its use is due to the presence of a collagen matrix in it, from which the nuclear elements of cells have been removed, which does not lead to immune aggression. The clinical case proves the expediency of using the decellularized dermal matrix of pig skin in the treatment of full-layer skin defects of various genesis.

Resurfacing the complex finger defect and sensation reconstruction with the free distal ulnar artery perforator flap: a self-controlled case series study.

BackgroundThe purpose of this clinical research is to report our results using the free distal ulnar artery perforator flap for resurfacing complex tissue defects in the finger, and to provide empirical reference for the treatment of subsequent clinical cases.MethodsIn our research, eight patients with complex skin defects were treated with free distal ulnar artery perforator flaps. There were 4 index, 3 long, and 2 ring fingers. All the flaps were raised from the ipsilateral ulnar lateral wrist. The donor sites were covered with a full thickness skin graft or closed by direct suture.ResultsComprehensive analysis of the clinical treatment process of eight patients, all flaps survived completely without any necrosis during the 6–18 months follow-up. The patients were satisfied with the finger mobility, the sensation function, and the aesthetic appearance.ConclusionsResurfacing complex tissue defects in the finger using the free perforator flap in a single stage, especially when the defect is medium in size and accompanied by digit nerve loss, is a valuable technique to achieve satisfaction in both sensation and aesthetic appearance. The ulnar artery perforator flap seems to be a reliable and flexible flap for addressing complex hand injuries with tissue loss.

Skin Traction Technique for Closure Large and Complex Skin Defects in Special Cases

Objective: During the period of COVID-19 pandemic, the reconstructive surgeons don't want to take risks of complex and long operations, and to struggle with long recovery time after surgery as well as with associated donor-site morbidity. Therefore, they prefer much more simple techniques. The objective of this study is to evidence that skin traction technique is a simple, short term, useful, and good option for closing open wound complex defect which needs the reconstruction with large flap.Methods: Skin traction techniques were applied to ten patients who had large complex defects in our clinic between March 2020 and March 2021. Patient’s data including demographic characteristic, comorbidities, causes of defects, anatomic localization of defects, size of defect, time of closure defect, time interval of tightening suture, number of tightening sutures, time of staying in hospital, general complication was recorded.Results: The study included 8 males and 2 females. The average age of patients was 42.8 years ranging from 22 to 60. The size of defects ranged between 8x5 cm and 18x10 cm with an average of 11.7x7.2 cm. The average duration of follow-up was 6 months. After 3 months, we evaluated subjectively quality of skin thickness, mobility, and colour. Skin was thinner and less mobile in the areas that were reconstructed with graft when compared with skin traction territories where the colour of skin was also normal in the cases with skin defect which was repaired by primarily closure after skin traction. All patients were satisfied with results. Complications such as skin necrosis at the traction site and hematoma were not observed. Superficial wound infection was seen in one patient, and it was resolved with antibiotherapy.Conclusions: We suggest using the traction suture technique for complex defects as an easy, cheap, and short-time procedure to reconstruct large and complex skin defects especially in recipient vessel problems, cases suffered from flap failure, patients with comorbidities and special conditions (for example, during the COVID-19 pandemic).

582 A Survey of Burn Care Providers Regarding the Utility of Telehealth to Provide Outpatient Burn Care

IntroductionTelehealth is purported to be the wave of the future, offering improved access to care by overcoming geographical and other logistical challenges while simultaneously improving efficiencies within the healthcare system. As the global COVID-19 pandemic swept through our state, we were abruptly forced to take our burn clinic to a telehealth platform for most patients. The purpose of this study was to evaluate our experience with telehealth in managing burn wounds and other complex skin defects.MethodsA 16-item survey was developed using the framework outlined by the National Quality Forum for the development of telehealth measures. The survey was distributed to direct care providers and focused on the domains of experience and effectiveness and the subdomains of efficiency and satisfaction.ResultsThere were a total of 14 respondents, including physicians, allied healthcare professionals, therapists and nurses. Seventy-seven percent of participants felt that overall, the system was efficient in the 4 categories of time required for scheduling, check-in, visit conduct and care coordination. Telehealth was deemed moderately to very effective by 80% in providing the patient access to care and the provider’s ability to educate the patient. However, providers, therapists and nurses uniformly found telehealth to be either not at all effective or slightly effective in assessing wounds, musculoskeletal function and developing a plan of care. When rating satisfaction with connectivity and overall quality of the clinic visit 70% of respondents were either dissatisfied/neither satisfied nor dissatisfied with the platform.ConclusionsThe operational aspects of our burn clinic telehealth program implemented during the COVID-19 pandemic were found to be largely satisfactory, with the exception of connectivity issues. However, the clinical aspects of the program were found to be largely unsatisfactory and, notably, were judged to be inferior to in-person visits.

329 Prognostic Indicators for Upper and Lower Extremity Amputations in a Verified Burn Center

Patients with burns or necrotizing soft tissue infections are at risk for significant morbidity. Extremities with extensive complex skin defects are at increased jeopardy. This may be increased by co-morbid conditions, yet prognostic indicators are not well defined in the literature. The purpose of this study was to identify and describe those potential prognostic factors found in the burn population patients requiring either upper or lower extremity amputation. This is a retrospective chart review of patients requiring amputation from 2000 - 2017. The co-morbidities of these patients were compared to patients that did not require amputation. Descriptive statistics and the relative risk of amputation for certain co-morbidities were calculated. During the study period there were a total of 110 patients requiring amputation versus 12,997 that did not. For those requiring amputations, burn injury was the most common precipitating event (59%) and flame flash was the most common mechanism (25%). The most frequent level of amputation was at the digit level (39%) followed by the transtibial level (33%). When amputees (AP) were compared to non-amputees (NA) there were significant differences between average (median) age, AP 49.9 (54.1) years vs. NA 34.3 (33.8) years (p < 0.001), TBSA AP 19.9% (6%) vs. NA 8.1% (4%, p=0.003) and length of stay AP 33.4 (26) days vs. NA 11.0 (7) days (p<0.001). Conditions associated with increased risk of amputation included cardiovascular disease (RR 4.3, p<0.001), liver disease (RR 4.8, p<0.001), renal insufficiency (RR 19.1, p<0.001), diabetes (RR 5.0, p <0.001), alcohol abuse (RR4.3, p<0.001) and smoking history (RR 4.1, p<0.001). Several comorbidities are associated with higher risk of amputation. Burn patients at higher risk of amputation are not only systematically different from non-amputees, but more specifically have greater restriction of blood flow from diabetes, cardiovascular disease and end stage renal disease which are the greatest afflictions leading to the need for an amputation. Future studies should investigate the role of circumferential burn injury, escharotomies / fasciotomies, as well as, the differences in amputation level between the upper versus lower extremity. This study gives providers quantified data to identify those patients at higher risk of amputation.

Pediatric Thermal Burns and Treatment: A Review of Progress and Future Prospects.

Burn injuries are a devastating critical care problem. In children, burns continue to be a major epidemiologic problem around the globe resulting in significant morbidity and death. Apparently, treating these burn injuries in children and adults remains similar, but there are significant physiological and psychological differences. The dermal layer of the skin is generally thinner in neonates, infants, and children than in adults. Enhanced evaporative loss and need for isotonic fluids increases the risk of hypothermia in the pediatric population. The pain management of the children with major burns challenges the skills of the personnel of every unit. Managing these wounds requires intensive therapeutic treatment for multi-organ dysfunction, and surgical treatment to prevent sepsis and other complications that further delay wound closure. Alternatives to the practice of donor site harvest and autografting for the treatment of severe burns and other complex skin defects are urgently needed for both adult and pediatric populations. This review article focuses on thermal burn pathophysiology and pain management and provides an overview of currently approved products used for the treatment of pediatric burn wounds. A new promising approach has been presented as a first-line therapy in the treatment of burns to reduce surgical autografting in pediatric patients.

Chimeric autologous/allogeneic constructs for skin regeneration.

The ideal treatment for severe cutaneous injuries would eliminate the need for autografts and promote fully functional, aesthetically pleasing autologous skin regeneration. NIKS progenitor cell-based skin tissues have been developed to promote healing by providing barrier function and delivering wound healing factors. Independently, a device has recently been created to "copy" skin by harvesting full-thickness microscopic tissue columns (MTCs) in lieu of autografts traditionally harvested as sheets. We evaluated the feasibility of combining these two technologies by embedding MTCs in NIKS-based skin tissues to generate chimeric autologous/allogeneic constructs. Chimeric constructs have the potential to provide immediate wound coverage, eliminate painful donor site wounds, and promote restoration of a pigmented skin tissue possessing hair follicles, sweat glands, and sebaceous glands. After MTC insertion, chimeric constructs and controls were reintroduced into air-interface culture and maintained in vitro for several weeks. Tissue viability, proliferative capacity, and morphology were evaluated after long-term culture. Our results confirmed successful MTC insertion and integration, and demonstrated the feasibility of generating chimeric autologous/allogeneic constructs that preserved the viability, proliferative capacity, and structure of autologous pigmented skin. These feasibility studies established the proof-of-principle necessary to further develop chimeric autologous/allogeneic constructs for the treatment of complex skin defects.

Clinical Evaluation of NIKS-Based Bioengineered Skin Substitute Tissue in Complex Skin Defects: Phase I/IIa Clinical Trial Results

Complex skin defects, such as burns and acute cutaneous trauma, are life-threatening injuries, often requiring temporary allograft placement to maintain fluid homeostasis and prevent infection until permanent wound closure is possible. The current standard of care for the management of full-thickness wounds that are unable to be closed in a single surgical stage is temporary coverage with cadaver allograft until an acceptable wound bed has been established. This approach has limitations including limited availability of human cadaver skin, the risk of disease transmission from cadaveric grafts, and inconsistent cadaver allograft quality. Near-diploid neonatal human keratinocyte cell line (NIKS)-based human skin tissue is a full-thickness, living human skin substitute composed of a dermal analog containing normal human dermal fibroblasts and a fully-stratified, biologically and metabolically active epidermis generated from NIKS keratinocytes, a consistent and unlimited source of pathogen-free human epidermal progenitor cells. NIKS-based human skin tissue is a living bioengineered skin substitute (BSS) intended to provide immediate wound coverage and promote wound healing through sustained expression by living cells of wound healing factors. A phase I/IIa clinical trial found that NIKS-based BSS was well tolerated and comparable to cadaver allograft in the ability to prepare full-thickness complex skin defects prior to autografting. There were no deaths and no adverse events (AE) associated with this BSS. Exposure of the study subjects to the skin substitute tissue did not elicit detectable immune responses. Notably, this tissue remained viable and adherent in the wound bed for at least 7 days.

A Bioengineered Human Skin Tissue for the Treatment of Infected Wounds

Complex skin defects resulting from acute skin trauma and chronic, nonhealing wounds are life-threatening injuries. Infection is one of the most common obstacles to the healing of these types of wounds. Host defense peptides (HDPs) possessing a broad spectrum of activity against microorganisms and serving as innate immune modulators have emerged as potential treatment strategies for infected wounds. The increase in multidrug-resistant clinical bacterial isolates highlights the need for new and innovative anti-infective therapies for the treatment of both acute and chronic skin wounds. To address the critical need for new therapeutic options to reduce infection and improve wound healing, a bioengineered skin substitute (BSS) tissue has been created to act as an anti-infective living human skin tissue that provides enhanced expression of the endogenous HDP, cathelicidin. To generate a BSS exhibiting these antimicrobial properties, the clinically tested NIKS progenitor cells were employed to provide a source of genetically uniform, nontumorigenic, pathogen-free human keratinocytes that are amenable to genetic engineering using nonviral means. Pathogenic bacterial strains are increasingly developing antibiotic resistance, thereby forcing the clinician to use potent antibiotics with deleterious effects on keratinocyte viability and migration. Therefore, an urgent need exists for new wound therapies that can circumvent many of the problems associated with current antibiotic treatments. Enhanced expression of cathelicidin in a genetically engineered human BSS has been shown to inhibit the bacterial growth of a multidrug-resistant clinical strain of Acinetobacter baumannii in vivo, creating a new and innovative therapeutic option for combating these debilitating wound infections while also promoting healing.

Phase I/II Clinical Evaluation of StrataGraft: A Consistent, Pathogen-Free Human Skin Substitute

Large wounds often require temporary allograft placement to optimize the wound bed and prevent infection until permanent closure is feasible. We developed and clinically tested a second-generation living human skin substitute (StrataGraft). StrataGraft provides both a dermis and a fully-stratified, biologically-functional epidermis generated from a pathogen-free, long-lived human keratinocyte progenitor cell line, Neonatal Immortalized KeratinocyteS (NIKS). Histology, electron microscopy, quantitative polymerase chain reaction, and bacterial growth in vitro were used to analyze human skin substitutes generated from primary human keratinocytes or NIKS cells. A phase I/II, National Institute of Health-funded, randomized, safety, and dose escalation trial was performed to assess autograft take in 15 patients 2 weeks after coverage with StrataGraft skin substitute or cryopreserved cadaver allograft. StrataGraft skin substitute exhibited a fully stratified epidermis with multilamellar lipid sheets and barrier function as well as robust human beta defensin-3 mRNA levels. Analysis of the primary endpoint in the clinical study revealed no differences in autograft take between wound sites pretreated with StrataGraft skin substitute or cadaver allograft. No StrataGraft-related adverse events or serious adverse events were observed. The major finding of this phase I/II clinical study is that performance of StrataGraft skin substitute was comparable to cadaver allograft for the temporary management of complex skin defects. StrataGraft skin substitute may also eliminate the risk for disease transmission associated with allograft tissue and offer additional protection to the wound bed through inherent antimicrobial properties. StrataGraft is a pathogen-free human skin substitute that is ideal for the management of severe skin wounds before autografting.

Temporal fascial flap: a versatile free flap for coverage of complex skin defects

The use of temporal fascial flap (TFF) as a microsurgical option permits the covering of skin defects which expose bones, nerves and vessels; it also provides a gliding surface which facilitates tendon excursion. Other advantages of the TFF are a reasonably constant surgical anatomy, minimal donor-site morbidity, and a thin and pliable surface which results in good cosmetic contour. In this paper we present our experience using TFF to cover wounds with significant exposed surfaces in different body areas (hands, feet, popliteal fossa); an average of 7 years follow-up is presented. Eleven patients with various wounds are presented: 91% had a successful surgery, and the TFF was able to solve the primary problem. On follow-up it was seen that the surgical aim had been reached, with excellent skin quality in terms of pliability, range of motion and protection from secondary ulceration. All patients were satisfied with the final result, and were able to return to their normal lifestyle. Scars secondary to flap harvesting were of good quality and were able to be hidden by the hair. No significant areas of alopecia were noticed.