Early recognition of limb necrotizing fasciitis and surgery within six hours is associated with a lower mortality risk and improved patient-reported outcomes

Aims: Necrotizing fasciitis (NF) is a rapidly progressive surgical emergency. The effects of time from hospital presentation to theatre on short- and long-term outcomes, as well as specific modifiable aspects of the care pathway that would enable early surgery, remain poorly defined. Methods: A retrospective cohort study of all suspected cases of limb NF presenting across a large health board region over ten years (January 2015 to April 2025) was undertaken. Early surgery was defined as ≤ six hours from presentation (triage time) to theatre (operation start time). The independent associations between surgical timing and 30-day mortality or amputation were assessed. A timeline analysis identified areas where delays occurred. Survivors completed the EuroQol five-dimension five-level questionnaire (EQ-5D-5L) and Toronto Extremity Salvage Score (TESS) outcome assessments. Results: Of 359 referrals, four patients died prior to surgery and 80 patients underwent emergency surgery due to surgeon suspicion of NF. For cases of intraoperatively confirmed NF (n = 63/80), early surgery was associated with a five-fold reduction in 30-day mortality rate (overall rate 22% (n = 14/63); adjusted hazard ratio 0.19, 95% CI 0.04 to 0.87, p = 0.032; absolute risk difference 25%). Additionally, early surgery was associated with reduced rates of 30-day amputation (overall rate 30% (n = 19/63); adjusted hazard ratio 0.19, 95% CI 0.05 to 0.66, p = 0.009; absolute risk difference 32%). At a median of 27 months' follow-up (IQR 16 to 48), only 35 patients (56%) were alive. Survivors having early surgery reported significantly better patient-reported outcomes (EQ-5D: 0.785 vs 0.133, p = 0.003; TESS combined: 64.9 vs 28.7, p = 0.007). Conclusion: Early surgery for patients with NF was associated with a lower risk of mortality, amputation, and severe long-term disability. Early recognition and transfer to theatre represent modifiable targets for improving survival and outcomes.