Pediatric Blunt Trauma Remains Confounding

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

UTI: Yet Another Windmill?

Medicine is full of windmills re-imagined as dragons – and two of the most prominent voices of reason in Emergency Medicine are David Newman and Jerome Hoffman.  This skeptical take on pediatric urinary tract infections is David Newman’s latest, which covers content reflective of his SMART EM podcast on the same topic.

The premise of his argument is rather straightforward:

  • There’s substantial overlap between UTI and asymptomatic bacteruria, leading to overdiagnosis.
  • Even when the diagnosis is correctly made, prompt treatment does not prevent complications.

The complications in question are urosepsis and renal scarring.  Urosepsis, in David’s literature review only results from urinary tract infections from the otherwise immunosuppressed, or in infants with congenital anomalies.  Renal scarring, purportedly from pyelonephritis, has little or controversial evidence in supporting antibiotic use from preventing it.

This will be published in an upcoming issue of Annals of Emergency Medicine.

“Pediatric Urinary Tract Infection: Does the Evidence Support Aggressively Pursuing the Diagnosis?”
www.ncbi.nlm.nih.gov/pubmed/23312370


Don’t Waste the Saline

This is a study that follows-up and confirms the prior “mythbusting” literature regarding the management of minor soft-tissue lacerations in the ED.  Specifically, this article evaluates the need for wound irrigation with sterile saline ($) as compared with tap water (free).

Unsurprisingly – and consistent with prior literature – this relatively contemporary study of 663 patients at Stanford University hospitals shows no difference in subsequent rates of wound infection, regardless of irrigation solution.  The sterile saline group suffered 6.4% (9.1 to 3.7%) subjective wound infections in follow-up, compared to 3.5% (5.5 to 1.5%) infections in the warm tap water irrigation.  A few patients were lost to follow-up, and the study has some generalizability limitations due to predefined exclusion criteria – frequently seen ED comorbidities such as diabetes, alcoholism, and immunocompromise were excluded.

But, it’s another piece of the puzzle that tells us suturing of uncomplicated wounds needs not be made more complicated.  There’s no evidence to suggest that anything more than tap water, absorbable sutures, and non-sterile techniques are needed for optimal patient outcomes.

Water is a safe and effective alternative to sterile normal saline for wound irrigation prior to suturing: a prospective, double-blind, randomised, controlled clinical trial”
http://bmjopen.bmj.com/content/3/1/e001504.full