Comparison of virtual bronchoscopy to fiber-optic bronchoscopy for assessment of inhalation injury severity

Purpose: Compare virtual bronchoscopy (VB) to fiberoptic bronchoscopy (FOB) for scoring smoke inhalation injury (SII).

Methods: Swine underwent computerized tomography (CT) with VB and FOB before (0) and 24 and 48 h after SII. VB and FOB images were scored by 5 providers off line.

Results: FOB and VB scores increased over time (p<0.001) with FOB scoring higher than VB at 0 (0.30±0.79 vs. 0.03±0.17), 24 h (4.21±1.68 vs. 2.47±1.50), and 48h (4.55±1.83 vs. 1.94±1.29). FOB and VB showed association with PaO2-to-FiO2 ratios (PFR) with areas under receiver operating characteristic curves (ROC): for PFR≤300, VB 0.830, FOB 0.863; for PFR≤200, VB 0.794, FOB 0.825; for PFR≤100, VB 0.747, FOB 0.777 (all p<0.001). FOB showed 80.3% specificity, 77% sensitivity, 88.8% negative-predictive value (NPV), and 62.3% positive-predictive value (PPV) for PFR≤300 and VB showed 67.2% specificity, 85.5% sensitivity, 91.3% NPV, and 53.4% PPV.

Conclusions: VB provided similar injury severity scores to FOB, correlated with PFR, and reliably detected airway narrowing. VB performed during admission CT may be a useful screening tool specifically to demonstrate airway narrowing induced by SII.