Red Blood Cell Transfusions and Anemia on Admission Are Associated with Poor Outcomes in Necrotizing Soft Tissue Infections

Background Necrotizing soft tissue infections (NSTIs) are highly morbid infections often requiring critical care and transfusion support. We explored a large 2-year experience from a regional trauma center with a dedicated soft tissue service (STS) in an attempt to identify factors in current care with potential for improving outcomes for these critically ill patients. Methods New adult (>17 years) STS admissions, 2008–2009, were identified from the Trauma Registry. Patient records were extracted and assessed via descriptive statistics, univariate analysis, and multivariable logistic regression models. Results Mortality among 253 eligible primary admissions was 8.3% overall and 10.3% for those with an admission diagnosis of NSTI. No significant differences in wound characteristics, use of VAC (vacuum-assisted closure) dressing or hyperbaric oxygen, or wound microbiology emerged between survivors and nonsurvivors. Median time to first debridement was 5 h (interquartile range, 2–21 h). Multivariable modeling indicated association of worse outcome (death or discharge to chronic/rehab care) with age >60 years [odds ratio (OR), 3.82; P < 0.001], anemia (OR, 0.98; P = 0.03), increasing number of transfusions (OR, 1.09; P < 0.001), NSTI diagnosis (OR, 2.47; P = 0.005), preexisting diabetes mellitus (OR, 3.20; P = 0.001), and low admission hemoglobin (OR, 0.80; P = 0.004). Conclusions Mortality was less than previously reported. Number of transfusions and anemia at admission emerged as risk factors for poor outcomes. Future research should focus on the effects of transfusion on NSTI outcomes, on potentially confounding factors, and on whether a restrictive transfusion strategy reduces mortality.