Pan-Scan & Zero-Miss

In an interesting contrast to a prior article regarding over-scanning in trauma, this article takes a different perspective.  While the authors do note that there is controversy regarding the impact of “pan scan” on survival, they are rather focused on the sensitivity/specificity of the “pan scan,” rather than the appropriateness.

This is a review of 982 consecutive patients undergoing “pan scan” in Germany.  The indications for scanning were a set of “red flag” criteria, which included impaired patients, patients with obvious injuries, “suspicion of severe trauma” or “high risk mechanism”.  The diagnostic reference standard was chart review by two reviewers of the electronic notes for any injuries missed on the initial scan.

The results are rather interesting in a couple ways:  the prevalence of injuries per organ system is not terribly high, and the sensitivity of scanning was rather low.  The highest prevalence of injuries for an organ system was 37%, for chest, followed by head and neck at 34%.  However, the sensitivities range from a high of only 86.7% for chest down to a low of 79.6% for face – likely because dedicated fine cuts of the face were not part of their protocol.  Regardless, with sensitivities in the mid-80s meant they missed almost one seventh of the total number of injuries.  Of these 70 missed injuries, almost half required surgery or a critical intervention as treatment.

So, pan-scanning: expensive, low yield, yet still misses important injuries.  The authors do not try to fully address whether their yield is reasonable or not, and wisely simply state further research is needed regarding triaging patients into groups likely to benefit from scanning.

“Accuracy of single-pass whole-body computed tomography for detection of injuries in patients with major blunt trauma.”
http://www.ncbi.nlm.nih.gov/pubmed/22392949