Comparison of Traditional and Skin-Sparing Approaches for Surgical Treatment of Necrotizing Soft-Tissue Infections

Appropriate surgical management in skin and soft tissue infections

PURPOSE OF REVIEW

To present standards and recent technical innovations in the surgical management of skin and soft tissue infections (SSTI).

RECENT FINDINGS

SSTI are a frequent cause of presentation in the acute care setting. They can range from simple and uncomplicated to severe and necrotizing infections. Surgical management plays an important role in the treatment of uncomplicated SSTI. Recent evidence indicates that a subgroup of patients (e.g. immunocompromised patients) profits from a postoperative course of antibiotic treatment of 5-7 days. In diabetic foot infections (DFI), repeated debridement to remove necrotic tissue and control infection can prevent minor and major amputation. In necrotizing soft tissue infections (NSTI), early and aggressive surgical debridement is paramount. Recent advancements have explored skin-sparing techniques in selective cases.

SUMMARY

The management of SSTIs requires a combination of surgical and antimicrobial strategies tailored to the type and severity of the infection. Further clinical research is necessary in order to define more accurately those collectives in severe SSTI who profit from a less aggressive surgical approach.

Hierarchical double-layer microneedles accomplish multicenter skin regeneration in diabetic full-thickness wounds

INTRODUCTION

Managing large chronic wounds presents significant challenges because of inadequate donor sites, infection, and lack of structural support from dermal substitutes. Hydrogels are extensively used in various forms to promote chronic wound healing and provide a three-dimensional spatial structure, through growth factors or cell transport.

OBJECTIVES

We present a novel multicenter regenerative model that is capable of regenerating and merging simultaneously to form a complete layer of skin. This method significantly reduces wound healing time compared to the traditional centripetal healing model. We believe that our model can improve clinical outcomes and pave the way for further research into regenerative medicine.

METHODS

We prepared a novel multi-island double-layer microneedle (MDMN) using gelatin-methacryloylchitosan (GelMA-CS). The MDMN was loaded with keratinocytes (KCs) and dermal fibroblasts (FBs). Our aim in this study was to explore the therapeutic potential of MDMN in a total skin excision model.

RESULTS

The MDMN model replicated the layered structure of full-thickness skin and facilitated tissue regeneration and healing via dual omni-bearing. Multi-island regeneration centres accomplished horizontal multicentric regeneration, while epidermal and dermal cells migrated synchronously from each location. This produced a healing area approximately 4.7 times greater than that of the conventional scratch tests. The MDMN model exhibited excellent antibacterial properties, attributed to the chitosan layer. During wound healing in diabetic mice, the MDMN achieved earlier epidermal coverage and faster wound healing through multi-island regeneration centres and the omnidirectional regeneration mode. The MDMN group displayed an accelerated wound healing rate upon arrival at the destination (0.96 % ± 0.58 % vs. 4.61 % ± 0.32 %). Additionally, the MDMN group exhibited superior vascularization and orderly collagen deposition.

CONCLUSION

The present study presents a novel skin regeneration model using microneedles as carriers of autologous keratinocytes and dermal fibroblasts, which allows for omni-directional, multi-center, and full-thickness skin regeneration.

Necrotizing Soft Tissue Infections: A Review

Importance

Necrotizing soft tissue infections (NSTIs) are severe life- and limb-threatening infections with high rates of morbidity and mortality. Unfortunately, there has been minimal improvement in outcomes over time.

Observations

NSTIs are characterized by their heterogeneity in microbiology, risk factors, and anatomical involvement. They often present with nonspecific symptoms, leading to a high rate of delayed diagnosis. Laboratory values and imaging help increase suspicion for NSTI, though ultimately, the diagnosis is clinical. Surgical exploration is warranted when there is high suspicion for NSTI, even if the diagnosis is uncertain. Thus, it is acceptable to have a certain rate of negative exploration. Immediate empirical broad-spectrum antibiotics, further tailored based on tissue culture results, are essential and should be continued at least until surgical debridement is complete and the patient shows signs of clinical improvement. Additional research is needed to determine optimal antibiotic duration. Early surgical debridement is crucial for improved outcomes and should be performed as soon as possible, ideally within 6 hours of presentation. Subsequent debridements should be performed every 12 to 24 hours until the patient is showing signs of clinical improvement and there is no additional necrotic tissue within the wound. There are insufficient data to support the routine use of adjunct treatments such as hyperbaric oxygen therapy and intravenous immunoglobulin. However, clinicians should be aware of multiple ongoing efforts to develop more robust diagnostic and treatment strategies.

Conclusions and Relevance

Given the poor outcomes associated with NSTIs, a review of clinically relevant evidence and guidelines is warranted. This review discusses diagnostic and treatment approaches to NSTI while highlighting future directions and promising developments in NSTI management.

IDENTIFICATION OF POTENTIALLY MODIFIABLE FACTORS TO IMPROVE RECOGNITION AND OUTCOME OF NECROTIZING SOFT-TISSUE INFECTIONS

ABSTRACT

Background : Necrotizing soft-tissue infections (NSTIs) present a surgical emergency of increasing incidence, which is often misdiagnosed and associated with substantial mortality and morbidity. A retrospective multicenter (11 hospitals) cohort study was initiated to identify the early predictors of misdiagnosis, mortality, and morbidity (skin defect size and amputation). Methods : Patients of all ages who presented with symptoms and were admitted for acute treatment of NSTIs between January 2013 and December 2017 were included. Generalized estimating equation analysis was used to identify early predictors (available before or during the first debridement surgery), with a significance level of P < 0.05. Results : The median age of the cohort (N = 216) was 59.5 (interquartile range = 23.6) years, of which 138 patients (63.9%) were male. Necrotizing soft-tissue infections most frequently originated in the legs (31.0%) and anogenital area (30.5%). More than half of the patients (n = 114, 54.3%) were initially misdiagnosed. Thirty-day mortality was 22.9%. Amputation of an extremity was performed in 26 patients (12.5%). Misdiagnosis was more likely in patients with a higher Charlson Comorbidity Index (β = 0.20, P = 0.001), and less likely when symptoms started in the anogenital area (β = -1.20, P = 0.003). Besides the established risk factors for mortality (septic shock and age), misdiagnosis was identified as an independent predictor of 30-day mortality (β = 1.03, P = 0.01). The strongest predictors of the final skin defect size were septic shock (β = 2.88, P < 0.001) and a skin-sparing approach to debridement (β = -1.79, P = 0.002). Conclusion : Recognition of the disease is essential for the survival of patients affected by NSTI, as is adequate treatment of septic shock. The application of a skin-sparing approach to surgical debridement may decrease morbidity.

The Role of Burn Centers in the Treatment of Necrotizing Soft-Tissue Infections: A Nationwide Dutch Study

Patients with extensive and complex wounds due to Necrotizing Soft-Tissue Infections (NSTI) may be referred to a burn center. This study describes the characteristics, outcomes, as well as diagnostic challenges of these patients. Patients admitted to three hospitals with a burn center for the treatment of NSTI in a 5-year period were included. Eighty patients (median age 54 years, 60% male) were identified, of whom 30 (38%) were referred by other centers, usually after survival of the initial septic phase. Those referred from other centers, compared to those primarily admitted to the study hospitals, were more likely to have group A streptococcal involvement (62% vs 35%, p = .02), larger wounds (median 7% vs 2% total body surface area, p < .001), and a longer length of stay (median 49 vs 22 days, p < .001). Despite a high incidence of septic shock (50%), the mortality rate was low (12%) for those primarily admitted. Approximately half (53%) of the patients were initially misdiagnosed upon presentation, which was associated with delay to first surgery (16 hours vs 4 hours, p < .001). Those initially misdiagnosed had more (severe) comorbidities, and less frequently reported pain or blue livid discoloration of the skin. This study underlines the burn centers' function as referral centers for extensively affected patients with NSTI. Besides the unique wound and reconstructive expertise, the low mortality rate indicates these centers provide adequate acute care as well. A major remaining challenge remains recognition of the disease upon presentation. Future studies in which factors associated with misdiagnosis are explored are needed.

The impact of necrotizing soft tissue infections on the lives of survivors: a qualitative study

PURPOSE

Necrotizing soft tissue infections (NSTI) are potentially lethal infections marked by local tissue destruction and systemic sepsis, which require aggressive treatment. Survivors often face a long recovery trajectory. This study was initiated to increase understanding of the long-term impact of NSTI on health related quality of life (HRQoL), and how care may be improved.

METHODS

Thematic analysis was applied to qualitative data from 25 NSTI-survivors obtained through two focus groups (n = 14) and semi-structured interviews (n = 11).

RESULTS

The median age of the participants was 49 years, 14 were female. The median time since diagnosis was 5 years. Initial misdiagnosis was common, causing delay to treatment. Survivors experienced long-term physical consequences (scarring, cognitive impairment, fatigue, sleeping problems, recurrent infections), psychological consequences (traumatic stress symptoms, fear of relapse, adjusting to an altered appearance, sexual issues) and social and relational consequences (changes in social contacts, a lack of understanding). The disease also had a major psychological impact on family members, as well as major financial impact in some. There was a strong desire to reflect on 'mistakes' in case of initial misdiagnosis. To improve care, patient and family centered care, smooth transitions after discharge, and the availability of understandable information were deemed important.

CONCLUSION

This study reveals that NSTI have a large impact on physical and psychosocial wellbeing of survivors and their relatives. Except for a few differences (misdiagnosis, fear for re-infection and actual re-infection), the patient experience of patients with NSTI is largely similar to those of burn survivors. Thus, questionnaires to assess HRQoL in burn survivors may be used in future NSTI studies.

Approaches to Surgical Debridement in Necrotizing Soft Tissue Infections: Outcomes of an Animated, Interactive Survey

Background

Necrotizing soft tissue infections (NSTI) affect long-term quality of life in survivors. Different approaches to debridement may influence quality of life. The aim of this study was to assess the current practice of the debridement of NSTI in the Netherlands.

Methods

An animated, interactive online survey was distributed among general surgeons and plastic surgeons in the Netherlands. Two NSTI-cases were presented, followed by questions regarding the preferred surgical approach. Case one described a woman with a swollen, red leg, with signs of sepsis and without visible necrosis. Case two described an immunocompromised man with septic shock syndrome and extensive necrosis.

Results

In total 232 responses were included (143 general surgeons, 89 plastic surgeons). In case one, 32% chose to preserve all skin, while 17% chose to resect all skin above the affected fascia, including normal-looking skin. In case two, all participants resected necrotic skin, and most (88%) also blue discolored skin. While 32% did not resect more than blue discolored and necrotic skin, 35% also resected red-colored skin, and 21% all skin overlying the affected fascia, including normal colored skin. Respondents working in a hospital with a burn center tended to preserve more skin, whereas plastic surgeons chose more often for skin resection compared to general surgeons.

Conclusions

By using a novel approach to a survey, the authors demonstrate the existence of extensive practice variety regarding the approach to debridement of NSTI among Dutch general and plastic surgeons. Consensus is needed, followed by targeted education of surgeons.

WSES/GAIS/WSIS/SIS-E/AAST global clinical pathways for patients with skin and soft tissue infections

Skin and soft-tissue infections (SSTIs) encompass a variety of pathological conditions that involve the skin and underlying subcutaneous tissue, fascia, or muscle, ranging from simple superficial infections to severe necrotizing infections.Together, the World Society of Emergency Surgery, the Global Alliance for Infections in Surgery, the Surgical Infection Society-Europe, The World Surgical Infection Society, and the American Association for the Surgery of Trauma have jointly completed an international multi-society document to promote global standards of care in SSTIs guiding clinicians by describing reasonable approaches to the management of SSTIs.An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting evidence was shared by an international task force with different clinical backgrounds.

Incidence and mortality of necrotizing fasciitis in The Netherlands: the impact of group A Streptococcus

BACKGROUND

Little is known about the exact incidence of necrotizing soft tissue infections. The few incidences reported in international literature are not directly relatable to the Netherlands, or other European countries, due to geographic heterogeneity in causative micro-organisms involved. This resulted in the aim of this study to map the incidence, mortality rate and hospital course of necrotizing fasciitis infections in the Netherlands to gain insight in the incidence of necrotizing fasciitis in the Netherlands and the associated mortality and health care burden.

METHODS

This nationwide retrospective database study used three distinct data sources to map the incidence of necrotizing fasciitis in the Netherlands between 2014 and 2019, being data from the Dutch Hospital Data (DHD) foundation, data from Osiris-AIZ, which is a database of notifiable diseases managed by regional Public Health Services (GGD) and the National Institute for Public Health and the Environment (RIVM), and previously published studies on necrotizing fasciitis conducted in the Netherlands.

RESULTS

The incidence of necrotizing fasciitis in the Netherlands is estimated to be approximately 1.1 to 1.4 cases per 100,000 person years, which corresponds to 193-238 patients per year. Of all necrotizing fasciitis infections, 34 to 42% are caused by the group A Streptococcus. Annually, 56 patients die as a result of a necrotizing fasciitis infection (mortality of 23-29%) and 26 patients undergo an amputation for source control (11-14%). Patients stay a mean of 6 to 7 days at the intensive care unit and have a mean hospital length of stay of 24 to 30 days.

CONCLUSION

The combination of nationwide databases provides reliable insight in the epidemiology of low-incidence and heterogenic diseases. In the Netherlands, necrotizing fasciitis is a rare disease with group A Streptococcus being the most common causative micro-organism of necrotizing fasciitis. The prior Dutch cohort studies on necrotizing fasciitis report slightly higher sample mortality rates, compared to the population mortality. However, necrotizing fasciitis remain associated with substantial morbidity and mortality, risk at amputation and health care burden characterized by prolonged ICU and hospital stay.

Necrotizing Soft Tissue Infections, the Challenge Remains

Background: Necrotizing Soft Tissue Infections (NSTIs) are uncommon rapidly spreading infection of the soft tissues for which prompt surgical treatment is vital for survival. Currently, even with sufficient awareness and facilities available, ambiguous symptoms frequently result in treatment delay.

Objectives: To illustrate the heterogeneity in presentation of NSTIs and the pitfalls entailing from this heterogeneity.

Discussion: NSTI symptoms appear on a spectrum with on one side the typical critically ill patient with fast onset and progression of symptoms combined with severe systemic toxicity resulting in severe physical derangement and sepsis. In these cases, the suspicion of a NSTI rises quickly. On the other far side of the spectrum is the less evident type of presentation of the patient with gradual but slow progression of non-specific symptoms over the past couple of days without clear signs of sepsis initially. This side of the spectrum is under represented in current literature and some physicians involved in the care for NSTI patients are still unaware of this heterogeneity in presentation.

Conclusion: The presentation of a critically ill patient with evident pain out of proportion, erythema, necrotic skin and bullae is the classical presentation of NSTIs. On the other hand, non-specific symptoms without systemic toxicity at presentation frequently result in a battery of diagnostics tests and imaging before the treatment strategy is determined. This may result in a delay in presentation, delay in diagnosis and delay in definitive treatment. This failure to perform an adequate exploration expeditiously can result in a preventable mortality.

The Skin-Sparing Debridement Technique in Necrotizing Soft-Tissue Infections: A Systematic Review

BACKGROUND

Skin-sparing debridement (SSd) was introduced as an alternative to en bloc debridement (EBd) to decrease morbidity caused by scars in patients surviving Necrotizing soft-tissue infections (NSTI). An overview of potential advantages and disadvantages is needed. The aim of this review was to assess (1) whether SSd is noninferior to EBd regarding general outcomes, that is, mortality, length of stay (LOS), complications, and (2) if SSd does indeed result in decreased skin defects.

METHODS

A systematic literature search was performed according to the PRISMA guidelines. All human studies describing patients treated with SSd were included, when at least of evidence level consecutive case series. Studies describing up to 20 patients were pooled to improve readability and prevent overemphasis of findings from single small studies.

RESULTS

Ten studies, one cohort study and nine case series, all classified as poor based on Chambers criteria for case series, were included. Compared to patients treated with EBd, patients treated with SSd had no increased mortality rate, LOS or complication rate. SSd-treated patients had a high rate (75%) of total delayed primary closure (DPC) in the pooled case series.

CONCLUSION

The current available evidence is of insufficient quality to conclude whether SSd is noninferior to EBd for all assessed outcomes. There are suggestions that SSd may result in a decreased need for skin transplants, which could potentially improve the (health related) quality of life in survivors. Experienced surgical teams could cautiously implement SSd under close monitoring, ideally with uniform outcome registry.