The latest output from the Pediatric Emergency Care Applied Research Network is a clinical decision instrument intended to assist clinicians in managing pediatric blunt abdominal trauma.
Like previous PECARN studies, this is a multi-center, prospective, observational study conducted in tertiary pediatric emergency departments. This study enrolled 12,044 children with blunt trauma and prospectively collected structured data regarding their mechanism, external injuries, and physiologic variables. Using the magic of statistical partitioning, the authors derived a decision instrument for use in risk-stratifying a patient as “very low risk for intra-abdominal injury requiring acute intervention.” If the patient meets all criteria, the prediction rule is 97.0% sensitive, missing 6 out of 203 abdominal injuries.
This is critically valuable data – but, as a decision-instrument in a zero-miss environment, I’m not sure if it helps. The authors note that use of their CT decision-instrument actually increased resource utilization if retrospectively applied to the derivation cohort, if the requirement is held that a patient be negative for every variable. If the threshold is raised to 1 or 2 variables present, then sensitivity drops to 82% and 77%, respectively. Only about half received a CT scan, and a small percentage were lost to follow-up – though, given the outcome of “injuries requiring intervention”, the methodology is reasonable. However, because intervention-requiring injuries only represented 26% of all radiographically-identified intra-abdominal injuries, this study is still going to be ignored out-of-hand by folks who want to identify all injuries, not just intervention-requiring injuries. After all, the grade 1 splenic laceration may be intervention-free, but remains important regarding activity restrictions to prevent future morbidity.
The authors also note these findings require external validation – wherever they’re going to find another pedatric emergency care network to enroll 12,000 patients!
“Identifying Children at Very Low Risk of Clinically Important Blunt Abdominal Injuries”
http://www.ncbi.nlm.nih.gov/pubmed/23375510