Validation of the AAST EGS grade for Skin and Soft Tissue Infection.

INTRODUCTION: Skin and soft tissue infections (SSTI) present with variable severity. The American Association for the Surgery of Trauma (AAST) developed an emergency general surgery (EGS) grading system for several diseases. We aimed to determine whether the AAST EGS grade corresponds with key clinical outcomes.

METHODS: Single institution retrospective review of patients (≥18 years) admitted with SSTI during 2012-2016 was performed. Patients with surgical site infections or <18 years were excluded. Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score and AAST EGS grade were assigned. The primary outcome was association of AAST EGS grade with complication development, duration of stay, and interventions. Secondary predictors of severity included tissue cultures, cross-sectional imaging, and duration of inpatient antibiotic therapy. Summary and univariate analyses were performed.

RESULTS: A total of 223 patients were included (mean ±SD age of 55.1±17.0 years, 55% male). The majority of patients received cross sectional imaging (169, 76%), or an operative procedure (155, 70%). SSTI tissue culture results included no growth (51, 24.5%), monomicrobial (83, 39.9%), and polymicrobial (74, 35.6%). Increased AAST EGS grade was associated with operative interventions, ICU utilization, complication severity (Clavien-Dindo index), duration of hospital stay, inpatient antibiotic therapy, mortality and hospital readmission.

CONCLUSION: The AAST EGS grade for SSTI demonstrates the ability to correspond with several important outcomes. Prospective multi-institutional study is required to determine its broad generalizability in several populations.

STUDY TYPE: Single institution retrospective review LEVEL OF EVIDENCE: IV.