Comparison of the diagnostic accuracy of CT scan with oral and intravenous contrast versus CT scan with intravenous contrast alone in the diagnosis of blunt abdominal trauma

Abstract

Purpose: Abdominal CT scan using oral and intravenous (IV) contrast is helpful in the diagnosis of intra-abdominal injuries. However, the use of oral and IV contrast delays the process of diagnosis and increases the risk of aspiration. It has also been shown that CT scan with IV contrast alone is as helpful as CT scan with oral and IV contrast and rectal CT scan in detecting abdominal injuries. Therefore, the present study aims to prospectively compare the diagnostic value of CT scan with oral and IV contrast versus CT scan with IV contrast alone in the diagnosis of blunt abdominal trauma (BAT).

Methods: Altogether 123 BAT patients, 60 (48.8%) women and 63 (51.2%) men with the mean age of (40.4 ± 18.7) years who referred to the emergency department of Imam Khomeini Educational and Medical Center in Sari, Iran (a tertiary trauma center in north of Iran) from November 2014 to March 2017 and underwent abdominal CT scans + laparotomy were investigated. Those with penetrating trauma or hemodynamically unstable patients were excluded. The participants were randomly allocated to two groups: abdominal CT scan with oral and IV contrast (n = 63) and CT scan with IV contrast alone (n = 60). No statistically significant difference was found between two groups regarding the hemodynamic parameters, age, gender, injury mechanisms (all p > 0.05). The results of CT scan were compared with that of laparotomy results. The collected data were recorded in SPSS version 22.0 for Windows. Quantitative data were presented as mean and SD.

Results: The sensitivity and specificity of CT scan using oral and IV contrast in the diagnosis of BAT were estimated at 96.48 (95% CI: 90.73 - 99.92) and 92.67 (95% CI: 89.65 - 94.88), respectively; while CT scan with IV contrast alone achieved a comparable sensitivity and specificity of 96.6 (95% CI: 87.45 - 99,42 and 92.84 (95% CI: 89.88 - 95.00), respectively.

Conclusion: CT scan with IV contrast alone can be used to assess visceral injuries in BAT patients with normal hemodynamics to avoid diagnostic delay.

Keywords: Blunt abdominal trauma; Contrast CT scan; Laparotomy.