Thoracic computed tomography is an effective screening modality in patients with penetrating injuries to the chest.

BACKGROUND: The precise role of thoracic CT in penetrating chest trauma remains to be defined. We hypothesized that thoracic CT effectively screens hemodynamically normal patients with penetrating thoracic trauma to surgery vs. expectant management (NOM). METHODS: A ten-year review of all penetrating torso cases was retrospectively analyzed from our urban University-based trauma center. We included hemodynamically normal patients (systolic blood pressure ≥90) with penetrating chest injuries that underwent screening thoracic CT. Hemodynamically unstable patients and diaphragmatic injuries were excluded. The sensitivity, specificity, positive predictive value and negative predictive value were calculated. RESULTS: A total of 212 patients (mean injury severity score=24, Abbreviated Injury Score for Chest=3.9) met inclusion criteria. Of these, 84.3% underwent NOM, 9.1% necessitated abdominal exploration, 6.6% underwent exploration for retained hemothorax/empyema, 6.6% underwent immediate thoracic exploration for significant injuries on chest CT, and 1.0% underwent delayed thoracic exploration for missed injuries. Thoracic CT had a sensitivity of 82%, specificity of 99%, positive predictive value of 90%, a negative predictive value of 99%, and an accuracy of 99% in predicting surgery vs. NOM. CONCLUSIONS: Thoracic CT has a negative predictive value of 99% in triaging hemodynamically normal patients with penetrating chest trauma. Screening thoracic CT successfully excludes surgery in patients with non-significant radiologic findings.

A novel CT volume index score correlates with outcomes in polytrauma patients with pulmonary contusion.

BACKGROUND: Exact quantification of pulmonary contusion by computed tomography (CT) may help trauma surgeons identify high-risk populations. We hypothesized that the size of pulmonary contusions, measured accurately, will predict outcomes. Our specific aims were to (1) precisely quantify pulmonary contusion size using pixel analysis, (2) correlate contusion size with outcomes, and (3) determine the threshold contusion size portending complications. METHODS: Thoracic CTs of 106 consecutive polytrauma patients with pulmonary contusion were evaluated at a university-based urban trauma center. A novel CT volume index (CTVI) score was calculated based on the ratio of affected lung to total lung [slices of lung on CT × affected pixel region/lung pixel region × 0.45 (left side) + slices of lung on CT × affected pixel region/lung pixel region × 0.55 (right side)]. Multivariate analysis correlated CTVI and patient predictors' impact on outcomes. RESULTS: Of 106 polytrauma patients (mean ISS = 28 ± 1.2, AIS chest = 3.5 ± 0.1), 39 developed complications (acute respiratory distress syndrome [ARDS], pneumonia, and/or death). Mean CTVI was significantly higher in the group with complications (0.28 ± 0.03 versus 17 ± 0.02, P = 0.01). By multivariate analysis, CTVI predicted longer ICU LOS (R(2) = 0.84, P < 0.01). A receiver operating curve (ROC) analysis identified a CTVI threshold score of 0.2 (AUC 0.67, P < 0.01) for developing pneumonia, ARDS or death. Patients with CTVI scores of 0.2 or more had longer hospitalization, longer ICU LOS, more ventilator days, and developed pneumonia (P < 0.01). CONCLUSIONS: Higher CTVI scores predicted prolonged ICU LOS across all sizes of pulmonary contusion. Pulmonary contusion volumes greater than 20% of total lung volume specifically identifies patients at risk for developing complications.