Assessment and determinants of global outcomes among 445 mass-casualty burn survivors: A 2-year retrospective cohort study in Taiwan.

PURPOSE: To study outcomes among survivors of the mass-casualty powder explosion on 27 June 2015, at Formosa Fun Coast Waterpark, New Taipei City, Taiwan. METHODS: Using retrospective data on Taiwanese survivors, we analyzed prehospital management, burns assessment and prognosis, functional recovery, and medical costs, followed-up through 30 June 2017. We related outcomes to burn extent, categorized according to the percentages of total body surface area with second/third-degree burns (%TBSA) or autologous split-thickness skin grafts (%STSG), and an investigational scale: f{SASG} = (%TBSA + %STSG)/2, stratified by %STSG. Analyses included casualty dispersal, comparisons between %TBSA, %STSG and f{SASG}, and their relationships with length of hospitalization, times to rehabilitation and social/school re-entry, physical/mental disability, and medical costs. We also investigated how burn scars restricting joint mobility affected rehabilitation duration. RESULTS: 445 hospitalized casualties (excluding 16 foreigners, 23 with 0% TBSA and 15 fatalities) aged 12-38 years, had mean TBSA of 41.1%. Hospitalization and functional recovery durations correlated with %TBSA, %STSG and f{SASG} - mean length of stay per %TBSA was 1.5 days; more numerous burn scar contractures prolonged rehabilitation. Females had worse burns than males, longer hospitalization and rehabilitation, and later school/social re-entry; at follow-up, 62.3% versus 37.7% had disabilities and 57.7% versus 42.3% suffered mental trauma (all p ≤ 0.001). Disabilities affecting 225/227 people were skin-related; 34 were severely disabled but 193 had mild/moderate impairments. The prevalence of stress-related and mood disorders increased with burn extent. Treatment costs (mean USD-equivalents ∼$48,977/patient, ∼$1192/%TBSA) increased with burn severity; however, the highest %TBSA, %STSG and f{SASG} categories accounted for <10% of total costs, whereas TBSA 41-80% accounted for 73.2%. CONCLUSIONS: Besides %TBSA, skin-graft requirements and burn scar contractures are complementary determinants of medium/long-term outcomes. We recommend further elucidation of factors that influence burn survivors' recovery, long-term physical and mental well-being, and quality of life.