Objective: To evaluate the utility of the Point of Care Ultrasound (POCUS) Focused Assessment with Sonography for Trauma (FAST) examination for diagnosis of intra-abdominal injury (IAI) in children presenting with blunt abdominal trauma.
Methods: We searched medical literature from January 1966 to March 2018 in PubMed, EMBASE, and Web of Science. Prospective studies of POCUS FAST examinations in diagnosing IAI in pediatric trauma were included. Sensitivity, specificity, and likelihood ratios (LR) were calculated using a random-effects model (95% confidence interval). Study quality and bias risk were assessed, and test-treatment threshold estimates were performed.
Results: Eight prospective studies were included encompassing 2135 patients with a weighted prevalence of IAI of 13.5%. Studies had variable quality, with most at risk for partial and differential verification bias. The results from POCUS FAST examinations for IAI showed a pooled sensitivity of 35%, specificity of 96%, LR+ of 10.84, and LR- of 0.64. A positive POCUS FAST posttest probability for IAI (63%) exceeds the upper limit (57%) of our test-treatment threshold model for computed tomography of the abdomen with contrast. A negative POCUS FAST posttest probability for IAI (9%) does not cross the lower limit (0.23%) of our test-treatment threshold model.
Conclusions: In a hemodynamically stable child presenting with blunt abdominal trauma, a positive POCUS FAST examination result means that IAI is likely, but a negative examination result alone cannot preclude further diagnostic workup for IAI. The need for computed tomography scan may be obviated in a subset of low-risk pediatric blunt abdominal trauma patients presenting with a Glasgow Coma Scale of 14 to 15, a normal abdominal examination result, and a negative POCUS FAST result.