In a recent note, I discussed how radiologists can use an algorithm to predict the likelihood of cardiovascular disease in chest CTs despite the fact that the procedure was not ordered for this purpose (see: Chest CT Used to Predict the Possibility of Future Cardiovascular Events). The clinical labs have used LIS-based algorithms, often called rules, for decades to prompt reflex testing and also to reduce unnecessary duplicate lab test ordering. A recent article discussed the use of an algorithm to reduce unnecessary pediatric abdominal CT's use in suspected appendicitis (see: Algorithm Cuts Pediatric CT Use in Suspected Appendicitis). Below is an algorithm from it:
A simple algorithm including components such as physical exam and ultrasound can help diagnose appendicitis in children and reduce the need for computed tomography (CT), researchers say. The algorithm, "built upon early involvement of the pediatric surgeon . . . decreases the use of imaging, including CT, without compromising diagnostic accuracy,"....Dr. Abdalla E. Zarroug...say use of CT in equivocal cases has increased, because its accuracy is reportedly above 94% - but "multiple studies" have suggested "that blood, brain, and solid organ cancers will develop owing to radiation exposure associated with CT."
To reduce use of CT in the emergency room in such cases, the team developed the algorithm. Among its elements are pediatric surgery consultation without any imaging in patients with unequivocal history, and physical exam and consultation prior to CT for patients with equivocal history, physical exam, and ultrasound results.
To evaluate the utility of the approach, the team examined five years' worth of data on 331 pediatric patients who had appendectomy after presenting to the emergency department. In the two years before algorithm implementation, 135 patients (40.8%) underwent appendectomy; the other 196 (59.2%) were seen in the three years after implementation.The use of CT fell significantly from 38% before algorithm implementation to 19% thereafter. The negative appendectomy rate increased slightly but not significantly from 9% to 11% after implementation.
For me, the bottom line here is the appropriateness of seeking a surgical consultation before ordering a CT on a pediatric patient. Because the CT rate fell dramatically in the study, we can assume that the surgeons were able to make the correct diagnosis at the bedside without the CT with only a small rise the the negative appendectomy rate. Although this seems obvious, I think we are beginning to see a broader use of algorithms prior to ordering expensive imaging procedures and perhaps greater emphasis on the development of bedside diagnostic skills.