The Utility of Ultrasound and Laboratory Data for Predicting Intra-abdominal Injury among Children with Blunt Abdominal Trauma

Background: Children with blunt abdominal trauma (BAT) can be risk stratified for intra-abdominal injury (IAI) through a combination of readily accessible clinical variables. The aim of this study was to identify ultrasound and laboratory studies that accurately identify IAI while limiting unnecessary CT-scan among children without injury. Materials and Methods We conducted a prospective, observational study of 2-12 years old children with BAT who referred to the emergency department (ED) at Al-zahra and Kashani hospitals in Isfahan city, Iran, from January 2013 to May 2014. Children were undergone abdominal ultrasound and abdominal CT scan was done at the discretion of the treating physicians and according to the CT protocols. The tests obtained to assess for an IAI were including hematocrit (HCT), amylase, aspartate aminotransferase (AST) or alanine aminotransferase (ALT) and urinalysis (U/A). The outcome were any IAI and intra-abdominal injury undergoing acute intervention (IAI-I). Results: We enrolled 101 children with a median age of 6.75 ± 3.2 years. There were 18 (17.8%) patients with IAI, and 5(5%) patients with IAI-I. The sensitivity, specificity and positive predictive value and negative predictive value of ultrasound compared to CT- scan were 72.2%, 85.5%, 52%, and 93.3%, respectively. It is notable that all 18 patients with IAI (Se=100%) had at least one positive test. The combination of ultrasound, ALT/AST, HCT, urinalysis and amylase tests (with at least one positive test) has negative predictive values of 100%. Conclusion: It can be argued that ultrasound combined with selected laboratory studies can be used to predict the risk of IAI accurately among children who sustain BAT. According to the results of this study, we can say that ultrasound and laboratory studies should be obtained as a screening tool in these cases.