The impact of operative time on the outcomes of necrotizing soft tissue infections: a multicenter cohort study

Background The primary aim of this study was to identify if there is an association between the operative time of the initial debridement for necrotizing soft tissue infections (NSTIs) and the mortality corrected for disease severity. Methods A retrospective multicenter study was conducted of all patients with NSTIs undergoing surgical debridement. The primary outcome was the 30-day mortality. The secondary outcomes were days until death, length of intensive care unit (ICU) stay, length of hospital stay, number of surgeries within first 30 days, amputations and days until definitive wound closure. Results A total of 160 patients underwent surgery for NSTIs and were eligible for inclusion. Twenty-two patients (14%) died within 30 days and 21 patients (13%) underwent an amputation. The median operative time of the initial debridement was 59 min (IQR 35–90). In a multivariable analyses, corrected for sepsis just prior to the initial surgery, estimated total body surface (TBSA) area affected and the American Society for Anesthesiologists (ASA) classification, a prolonged operative time (per 20 min) was associated with a prolonged ICU (β 1.43, 95% CI 0.46–2.40; p = 0.004) and hospital stay (β 3.25, 95% CI 0.23–6.27; p = 0.035), but not with 30-day mortality. Operative times were significantly prolonged in case of NSTIs of the trunk (p = 0.044), in case of greater estimated TBSA affected (p = 0.006) or if frozen sections and/or Gram stains were assessed intra-operatively (p < 0.001). Conclusions Prolonged initial surgery did not result in a higher mortality rate, possible because of a short duration of surgery in most studied patients. However, a prolonged operative time was associated with a prolonged ICU and hospital stay, regardless of the estimated TBSA affected, presence of sepsis prior to surgery and the ASA classification. As such, keeping operative times as limited as possible might be beneficial for NSTI patients.

Laboratory risk indicator for necrotizing fasciitis: an objective scoring system as a tool for early diagnosis of necrotizing fasciitis

Background: Necrotizing soft tissue infections are often fatal, characterized by extensive necrosis of the subcutaneous tissues and fascia. The mortality of 30-40% reflects the inadequacy of early recognition of necrotizing soft tissue infections. This study emphasizes on the search for a tool that reliably and rapidly identifies patients with NF. An objective of current study was to validate the LRINEC score as a tool for early distinguishing of necrotizing fasciitis from other soft tissue infections.Methods: Prospective clinical study analysis of outcome of sixty of patients with soft tissue infections were evaluated based on LRINEC. Based on their LRINEC score, the patients were categorized as low, intermediate and high risk for the onset of necrotizing fasciitis.Results: A total of 60 patients with soft tissue infections were prospectively evaluated and categorized on the basis of LRINEC score 45 patients in low risk category, 7 in Intermediate risk and 8 patients in high risk group. In terms of outcome, all cases (including positive tissue diagnosis cases) in low risk and intermediate risk groups and 2 cases in high risk group were improved with surgical debridement/fasciotomy. The cutoff of LRINEC ≥6 has better sensitivity and specificity in identifying the risk of the patient.Conclusions: LRINEC scoring system has a better positive predictive value in identifying the onset and risk strategizing of necrotizing fasciitis.

Necrotizing Bacterial Myositis as the Initial Presentation of Severe Aplastic Anaemia

Introduction. Necrotizing soft tissue infections are rapidly progressing infections associated with severe inflammation and cytokine release. Early recognition and surgical intervention are key factors to secure survival. The current case presents a patient with multifocal necrotizing soft tissue infection as the initial presentation of severe aplastic anaemia. Case Presentation. A man in his fifties was admitted with septic shock with multiorgan failure and severe pancytopenia, after two days of malaise with high fever and right flank pain. The diagnosis streptococcal necrotizing myositis was significantly delayed due to atypical clinical findings. After initial surgical exploration, the decision was made to defer from surgical debridement due to extensive involvement of several muscle groups, grave pancytopenia, and suspected dismal prognosis. Surprisingly, the patient stabilized after antibiotics and intensive care treatment. Based on severe pancytopenia and hypocellular bone marrow, with no evidence of other bone marrow disorders, the patient was diagnosed with aplastic anaemia. Treatment for aplastic anaemia with antithymocyte globulin, cyclosporine, and eltrombopaq was started, and 2 months later, a partial haematological recovery was observed. The patient could be discharged from hospital without antibiotic treatment. Conclusions. This case illustrates the crucial role of a multidisciplinary approach on admission and further during the clinical course. Clinical improvement despite severe neutropenia and stabilization during immunosuppressive therapy suggest that immunological factors modulate clinical course in necrotizing soft tissue infections.

Effect of Hyperbaric Oxygenation on Blood Cytokines and Arginine Derivatives; No Evidence for Induction of Inflammation or Endothelial Injury

(1) Background: Hyperbaric oxygen therapy (HBOT) uses 100% oxygen delivered at 1.5–3 times the atmospheric pressure in a specialised chamber to achieve supraphysiological oxygen tension in blood and tissues. Besides its target, HBOT may affect inflammation, endothelial function or angiogenesis. This study analysed the effect of HBOT on blood concentrations of factors that may affect these processes in patients with necrotizing soft-tissue infections (NSTI), aseptic bone necrosis (ABN) and idiopathic sudden sensory neural hearing loss (ISSNHL). (2) Methods: Concentrations asymmetric dimethylarginine (ADMA) and other arginine derivatives were measured with liquid chromatography/mass spectrometry, whereas ELISA was used to quantitate vascular endothelial growth factor (VEGF) and cytokines (IL-1, IL-4, IL-6, IL-10, TGF-β) before and after HBOT in 80 patients (NSTI n = 21, ISSNHL n = 53, ABN n = 6). (3) Results: While some differences were noted between patient groups in ADMA and other arginine derivatives as well as in cytokine concentrations, HBOT did not affect any of these parameters. (4) Conclusions: While cytokines and arginine derivatives concentrations were modified by underlying pathology, hyperbaric oxygenation did not immediately modify it suggesting that it is neutral for inflammation and is not inducing endothelial injury.

From the Cochrane Library: Interventions for necrotizing soft tissue infections in adults (Preprint)

UNSTRUCTURED Summary for the Cochrane review Interventions for necrotizing soft tissue infections in adults

Short Courses of Antibiotics Are Safe in Necrotizing Soft Tissue Infections

Introduction Necrotizing soft tissue infections (NSTIs) carry high morbidity and mortality. While early aggressive surgical debridement is well-accepted treatment for NSTIs, the optimum duration of adjunct antibiotic therapy is unclear. An increasing focus on safety and evidence-based antimicrobial stewardship suggests a value in addressing this knowledge gap. Objective To determine whether shorter antibiotic courses have similar outcomes compared to longer courses in patients with NSTI following adequate source control. Population 142 consecutive patients with surgically managed NSTI were identified on retrospective chart review between December 2014 and December 2018 at two academic medical centers. Results Patients were predominately male (74%) with a median age of 52 and similar baseline characteristics. The median number of debridements to definitive source control was 2 (IQR 1-3) with the short course group undergoing a greater number of debridements control 2.57 ± 1.8 vs 1.9 ± 1.2, ( P = .01). Of 142 patients, 34.5% received a short course and the remaining 65.5% received a longer course of antibiotics. There was no significant difference in the incidence of bacteremia or wound culture positivity between groups. There was also no significant difference in in-hospital mortality, 8% vs 6, ( P = .74), incidence of C. difficile infection, median length of stay, or 30-day readmission. Conclusion Provided adequate surgical debridement, similar outcomes in morbidity and mortality suggest antibiotic courses of 7 days or less are equally safe compared to longer courses.