External retrospective validation of the STUMBL score for patients with isolated blunt thoracic trauma presenting to the emergency department.

Abstract

Introduction: Blunt Thoracic trauma (BTT) affects over 10 % of trauma patients and may lead to delayed respiratory complications. The STUMBL (STUdy of the Management of BLunt chest wall trauma) score was developed to identify patients at high risk of complications. This study aimed to validate the STUMBL score in a Canadian setting.

Methods: We conducted a retrospective cohort study of adult patients with isolated BTT presenting to a Canadian emergency department (ED) of a Level-1 trauma center between 2018 and 2020. STUMBL scores were calculated for each patient. The primary outcome was a composite of in-hospital mortality, early pulmonary complications, ICU admission, or prolonged hospital stay (≥7 days). Secondary outcomes were delayed pulmonary complications and unplanned return to the ED. Receiver operating characteristic (ROC) curves were used to evaluate predictive performance, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were computed for each score cutoff.

Results: Among 344 included patients (mean age: 57.8 ± 17.0, male sex: 64.2 %), 18.3 % experienced the primary outcome. The STUMBL score showed good discrimination (AUROC 0.87). A cutoff of ≤10 yielded a sensitivity of 90.5 % and NPV of 97.0 %, while a cutoff of ≤15 showed a sensitivity of 66.7 % and NPV of 92.2 % to predict the composite outcome. In patients with a score ≤15, delayed pulmonary complications occurred in <2 %, and unplanned ED visits in <7 %. Conversely, 82.4 % of patients with STUMBL scores ≥21 experienced the composite outcome. This cutoff was associated with a specificity of 97.9 % and PPV of 82.4 %.

Conclusions: The STUMBL score demonstrated good performance in predicting early adverse outcomes in Canadian patients with isolated BTT. Patients with a STUMBL score ≤15 and no early complications represent a low-risk group that may be safely discharged. Those with scores ≥21 warrant ICU evaluation. Further prospective validation or refinement is recommended before widespread implementation.