Commentary: The role of sonography in the initial evaluation of children after blunt abdominal trauma

Doctors Taylor and Kaufman have posed and tried to answer several provocative questions regarding the usefulness of ultrasound (US) in the initial evaluation of children after blunt abdominal trauma [1]. Their well-referenced commentary highlights both the accuracy of US (-95 %) in detecting the presence of free fluid in the abdomen as well as the discouraging rates of detection of solid organ injuries by US in the acute period from several small series. The lack of definition of abdominal injuries by US should warrant caution from a trauma radiologist. In support of computed tomography (CT) they subjectively add that "more precise management of specific injuries is permitted when the exact nature and extent of injury are known". However, children with solid organ injuries are not selected for operation or transfusion based on CT grade of injury or quantity of hemoperitoneum. The first question that needs answering is, "Will an US help the clinician triage and treat a child with blunt abdominal trauma. From a trauma surgeon's perspective, US can provide valuable triage information despite this lack of specific injury definition when compared to CT [3, 4]. Sonography offers several attractive advantages compared to CT in the initial evaluation of at least two subgroups of patients; those with low-probability assessment for abdominal injury on clinical grounds and those children with multi-system injuries. While abdominal CT remains the gold standard imaging modality in evaluating children after blunt abdominal trauma, Taylor and Eichelberger have documented the rate of negative CT examinations of up to 80 % in select groups [2]. In the child with multi-system injuries a prompt Emergency Department abdominal sonogram could help place priority on further diagnostic and therapeutic algorithms. Assessment of the presence of free intraabdominal fluid or major solid organ disruption without the need to move the patient to areas of the hospital remote from proper observation and monitoring would be an obvious advantage and allow thoracic, orthopedic, peripheral vascular and neurologic interventions to proceed in a timely, orderly fashion. This information would be extremely helpful in the child requiring emergency, non-abdominal surgery for the surgeons and anesthesiologists. However, the high incidence of head trauma in children with multi-system injuries and the CNS imaging required may negate the advantage of the portable nature of US. Sonography may provide an even greater advantage in "screening" children after minimal abdominal trauma. Those of us with near immediate access to a CT are thankful for the intraabdominal definition provided. But do we need CT in every child who needs screening or would we do just as well with US? Certainly abnormalities on US could then be investigated further. The role of US as an earlyimaging study willnot replace the CT but rather select those patients who were more apt to benefit by the information available on CT. f think we would be drastically reducing the unnessesary number of CTs, IVPs and isotope studies done in the group with low suspicion for abdominal injury with early use of US. These comments are based on the value of US in many clinical settings outside of trauma. Ultrasound is a reliable, objective, non-invasive, quickto-perform, inexpensive method of evaluating the abdomen. Clearly, a study of US in the initial evaluation of children alter blunt abdominal trauma will need verification by CT, celiotomy, or autopsyin aprospective series with clearly defined cohorts. Until such a study is reported we should continue to ask, "Will an US in the Emergency Department help me manage this injured child?" I believe the answer is yes.