US in blunt abdominal trauma: need to be there 24 hours a day!

Abstract

Purpose: To evaluate the utility of routine abdominal ultrasound (US) as first diagnostic imaging method 24 h a day in a series of patients admitted with blunt abdominal trauma to our level II trauma center. Methods: Two thousand four hundred and eleven consecutive patients admitted after blunt abdominal trauma over 12 months were prospectively evaluated using abdominal US. The examinations were performed within 25 min after admission. An experienced senior radiologist was available on site 24 h a day (including holidays) to perform all the US examinations. The US examination included a full abdominal exploration. The US results were compared to findings at computed tomography (n = 115), clinical follow-up (n = 2244), or surgery (n = 47). Results: Overall, 2411 US abdominal studies were performed. In 5/2411 (0.2 %) patients, the US examinations were incomplete or indeterminate because of patient obesity and were therefore excluded from the study. Of the remaining 2406 US studies, 265 (11 %) were performed between 0 and 6 a.m., 770 (32 %) were performed between 6 a.m. and 12 midday, 673 (28 %) were performed between 12 midday. and 6 p.m., and the remaining 698 (29 %) were performed between 6 and 12 p.m. At US, the following post-traumatic injuries were correctly detected: 67 splenic lesions, 62 liver injuries, 13 renal contusions, 2 bowel lacerations, and 1 pancreatic injury. Nineteen patients had a sonogram with negative findings followed by CT with positive findings, while 18 patients had a sonogram with positive findings followed by CT with negative findings. The following rates were calculated for the US studies: true negative = 2224; true positive = 145; false positive = 18; false negative = 19; sensitivity = 88.4 %; specificity = 99.2 %; diagnostic accuracy = 98.2 %; positive predictive index = 88.9 %; negative predictive index = 99.1 %. Conclusion: Abdominal US provides a highly accurate, noninvasive imaging evaluation in patients who have sustained blunt abdominal trauma. This can be obtained particularly if a team of senior radiologists can perform the examination to provide high quality sonograms and be on site 24 h a day.