Unenhanced Computed Tomography to Visualize Hollow Viscera and/or Mesenteric Injury After Blunt Abdominal Trauma: A Single-Institution Experience

Diagnostic accuracy of computed tomography findings for hollow viscus injuries following thoracoabdominal gunshot wounds

BACKGROUND

Selective nonoperative management (SNOM) of abdominal gunshot wounds (GSWs) is increasingly used as computed tomography (CT) has become a diagnostic adjunct for the evaluation of intraabdominal injuries including hollow viscus injuries (HVIs). Currently, there is scarce data on the diagnostic accuracy of CT for identifying HVI. The purpose of this study was to determine the diagnostic accuracy of different CT findings in the diagnosis of HVI following abdominal GSW.

METHODS

This retrospective single-center cohort study was performed from January 2015 to April 2019. We included consecutive patients (≥18 years) with abdominal GSW for whom SNOM was attempted and an abdominal CT was obtained as a part of SNOM. Computed tomography findings including abdominal free fluid, diffuse abdominal free air, focal gastrointestinal wall thickness, wall irregularity, abnormal wall enhancement, fat stranding, and mural defect were used as our index tests. Outcomes were determined by the presence of HVI during laparotomy and test performance characteristics were analyzed.

RESULTS

Among the 212 patients included for final analysis (median age: 28 years), 43 patients (20.3%) underwent a laparotomy with HVI confirmed intraoperatively whereas 169 patients (79.7%) were characterized as not having HVI. The sensitivity of abdominal free fluid was 100% (95% confidence interval [CI]: 92-100). The finding of a mural defect had a high specificity (99%, 95% CI: 97-100). Other findings with high specificity were abnormal wall enhancement (97%, 95% CI: 93-99) and wall irregularity (96%, 95% CI: 92-99).

CONCLUSION

While there was no singular CT finding that confirmed the diagnosis of HVI following abdominal GSW, the absence of intraabdominal free fluid could be used to rule out HVI. In addition, the presence of a mural defect, abnormal wall enhancement, or wall irregularity is considered as a strong predictor of HVI.

LEVEL OF EVIDENCE

Diagnostic Test or Criteria; Level II.

The Current Diagnostic Accuracy on Free Peritoneal Fluid in Computed Tomography to Determinate the Necessity of Surgery in Blunt Bowel and Mesenteric Trauma-Systemic Review and Meta-Analysis

Traumatic bowel mesenteric injury (TBMI) is a challenge in trauma care. The presence of free peritoneal fluid (FF) in computed tomography (CT) was considered the indication for surgical intervention. However, conservative treatment should be applied for minor injuries. We conduct a systematic review to analyze how reliable the FF is to assess the TBMI. Publications were retrieved by structured searching among databases, review articles and major textbooks. For statistical analysis, summary receiver operating characteristic curves (SROCs) were computed using hierarchical models. Fourteen studies enrolling 4336 patients were eligible for final qualitative analysis. The SROC line was created by a hierarchical summary receiver operating characteristic model. The summary sensitivity of FF to predict surgical TBMI was 0.793 (95% CI: 0.635-0.894), and the summary specificity of FF to predict surgical TBMI was 0.733 (95% CI: 0.468-0.896). The diagnostic odds ratio was 10.531 (95% CI: 5.556-19.961). This study represents the most robust evidence (level 3a) to date that FF is not the absolute but an acceptable indicator for surgically important TBMI. However, there is still a need for randomized controlled trials to confirm.