Understanding the relevance of comprehensive facial injury (CFI) score: Statistical analysis of overall surgical time and length of stay outcomes.

Comprehensive facial injury (CFI) score is a powerful and extremely simple scale used to grade the clinical severity of all facial injuries, and is expressed in terms of the overall surgical time needed for definitive treatment. Its statistical validation was previously reported in 2019. The aim of this study was to investigate further the link with duration of surgery, applying the score to a larger sample of patients, and to evaluate the relationship between CFI score and other extremely relevant dependent variables: length of stay (LOS) in high care units (HCU) and in intensive care units (ICU). 1406 patients with diagnosis of at least one facial bone fracture, and treated by the same team in two highly specialized trauma centers, were studied. For each patient a specific CFI score is assigned and overall surgical time, length of stay, and presence of associated injuries were recorded. Data were divided into six clusters according to CFI score: (1) 0-5, (2) 6-10, (3) 11-15, (4) 16-20, (5) 21-25, and (6) >25. Regressions between CFI clusters and duration of surgery (minutes), LOS in ICU (days), and in HCU (days) were established. In addition, the presence of associated head and/or somatovisceral injuries was analyzed and related to CFI score. Statistical analysis confirmed linear regression existing between each CFI cluster and overall surgical time (p < 0.00001), with improved significance of the results using median values of surgical duration for each cluster (p = 0.0001). It also demonstrated the existence of linear regression between all CFI clusters and LOS in HCU (p = 0.0001) and between CFI clusters 3-6 and median values of LOS in ICU (p = 0.0001). Finally, associated injuries were observed to be more frequent in high CFI score clusters, occurring in around 90% of patients with a CFI score >25 (p < 0.00001). Association of head and facial injuries play a major role in high LOS in ICU values, whereas coexistence of facial, head and somatovisceral involvement increases LOS in ICU to over twice that for single association. Surgical time and length of stay are outcomes traditionally used to assess the statistical significance of many new proposed trauma score. The strong correlation demonstrated between CFI score and each of these variables confirms its value and reliability. CFI score is proven to be an ideal, simple, informative, and reproducible tool for measuring severity of facial injuries and their clinical impact. It allows correlation with associated head and somatovisceral injuries, focusing attention on the interesting field of reciprocal influences in simultaneous, multidistrectual involvement. None of the previously proposed facial injury severity scales have offered such informative and statistically significant features.