The role of iv contrast medium in diagnostic blunt abdominal trauma CT scan at Kenyatta National Hospital (KNH) – Kenya

Abstract

Background: Previous studies have proven the intravenous contrast CT to be the cornerstone of the diagnostic work-up of abdominal trauma, essentially for evaluating solid parenchymal and vascular injuries. This study was aimed at determining the utility of IV contrast medium in diagnostic blunt abdominal trauma CT scan at Kenyatta National Hospital (KNH), since IV contrast medium was not routinely used in KNH for blunt abdominal trauma CT scan. Methods: A standard questionnaire was used to record the socio-demographic characteristics of the study participants, the mode of trauma and CT scan findings. All patients sent for initial diagnostic abdominopelvic CT scan with recent history of blunt abdominal trauma, who could receive IV contrast medium and who consented participation over the study period made the study population. Each participant underwent at least two consecutive scans, one scan without IV contrast medium and another one with IV contrast medium for comparison of findings. For IV contrast scans a portal venous phase scan at 65 seconds and a delayed phase scan at 5 minutes after starting IV contrast injection were acquired to every patient in our study. Results: Thirty nine patients were enrolled into the study. The male to female ratio was 3.8:1. Twenty one patients (53.9%) were in the age group of 21-40 years. Thirty patients (76.9%) sustained abdominal injuries following motor traffic accidents. The spleen was the most commonly injured organ (41%), followed by the liver (38%) and the kidneys (15%). Hemoperitoneum was the most common CT finding (17 patients) and out of 115 injuries registered in our study, pre contrast scans could only detect 45 injuries which correspond to 39.1% (95 % CI 30.2 – 48.7). This means that 60.9% (95% CI 51.3 – 69.8) of injuries would have been missed without contrast injection. Conclusion: The use of IV contrast medium assisted in the demonstration of 60.9 % (95% CI 51.3 – 69.8) of injuries that would have been missed without contrast injection. This confirms the usefulness of IV contrast injection in blunt abdominal CT scan. Recommendations: In order to reach definite conclusions larger series are needed. Diagnostic protocol for management of patients with blunt abdominal injuries should be made and be available for guiding radiologists and surgeons on management of patients with abdominal injuries. A study to evaluate the accuracy of CT scan in the detection of blunt abdominal injuries by comparing CT findings and operative findings is needed.