Urinary bladder volume measured in whole-body CT scans is a useful marker for alcohol

Purpose: The aim of this study was to investigate whether urinary bladder volume (UBV) and blood alcohol concentration (BAC) correlate in a cohort of emergency trauma patients. Furthermore, the feasibility of semi-automated 3D-CT volumetry for urinary bladder volumetry calculations in whole-body CT examinations was elucidated. Material and methods: Whole-body CT scans of 831 individuals treated in the emergency department with suspected multiple injuries were included. Manual 3D-CT volumetry of the urinary bladder was performed and the mechanism of injury, patient demographics, BAC, serum creatinine, and hematocrit were retrospectively analyzed. Semi-automated calculation of UBV was performed in 30 patients. Statistical analysis included ROC analysis to calculate cut-off values, sensitivity, and specificity. The Mann Whitney test and Spearman's correlation coefficient were used to detect significant correlations between UBV and BAC. Results: Manual 3D-CT volumetry showed maximum sensitivity and specificity with a cut-off value for urinary bladder volume of 416.3 mL (sensitivity 50.9%; specificity 76.3%; AUC 0.678). With a cut-off value of 4.2 mL/mu mol for the creatinine quotient (quotient of serum creatinine and UBV), the sensitivity was 64.2% (specificity 67.0%; AUC 0.681). Semi-automated 3D-CT volumetry resulted in lower UBV values compared to those obtained with manual 3D-CT volumetry. Conclusion: Semi-automated 3D-CT volumetry is a reliable method to quantify UBV. UBV correlates with positive BAC results. A UBV above 416 mL seen on an initial whole-body CT must raise suspicion of alcohol intoxication. The creatinine quotient is an even more sensitive and specific parameter for the detection of alcohol intoxication. (C) 2017 Elsevier Inc. All rights reserved.