JACR: Appropriate use of CT in ED complex, achievable
With CT—and, to an extent, emergency medicine—in the cross-hairs when it comes to imaging utilization and radiation exposure, the American College of Radiology and other stakeholders met in 2009 to outline appropriate use of CT in emergency medicine. A summary of recommendations was published in the May issue of Journal of American College of Radiology. 

The annual number of CT scans in the U.S. reached 72 million in 2008, with approximately one-third of the studies performed in emergency departments (EDs). Concurrent issues include the relatively high costs of CT compared with other imaging modalities as well as radiation exposure.

Against this backdrop, the National Council on Radiation Protection and Measurements (NCRP) convened a workshop—Computed Tomography in Emergency Medicine: Ensuring Appropriate Use—Sept. 23 and 24, 2009. Organizations represented at the workshop were American Association of Physicists in Medicine (AAPM), American College of Emergency Physicians (ACEP), ACR, American Society of Emergency Radiology, Centers for Disease Control and Prevention, Landauer, Society for Academic Emergency Medicine and the U.S. Environmental Protection Agency.

Workshop participants acknowledged the clinical utility of CT in the detection and diagnosis of trauma and chest pain patients. “Diagnosis and management of fatal diseases such as aortic dissection, pulmonary emboli and others have been revolutionized with CT imaging,” wrote Otha Linton, of the International Society of Radiology and NCRP, in Bethesda, Md.

Participants also referred to the duties of emergency physicians, explaining that they have to “identify, treat or exclude life-threatening or limb-threatening conditions” even if the tentative diagnosis is disease, not trauma. In fact, the Emergency Medical Treatment and Active Labor Act (EMTALA) mandates this approach. In many cases, the authors pointed out, CT offers the most appropriate and efficacious means to evaluate the patient.

At the same time, physicians seeking diagnostic information are responsible for determining a benefit-risk decision for CT imaging for each patient. Meanwhile, radiologists and technologists are responsible for implementing radiation dose controls.

Medicolegal factors also enter into the equation, offered the authors, because patients, and sometimes lawyers, may question an ED physician’s decision not to order a CT study. Hence, defensive ordering pervades the healthcare system.

“With CT scans often regarded as the optimal imaging procedure, a decision to exclude imaging, based on the clinical assessment, raises the possible accusation that a failure to get the information revealed by a properly interpreted CT scan (an act of omission) is a worse violation of good practice than the decision to undertake a procedure that may have limited value of a greater risk than benefit,” wrote Linton.

In general, the benefits of CT typically support its use over other imaging modalities, said Linton and colleagues, who offered the nine recommendations that arose from the workshop:

1.       Educate providers about ACR Appropriateness Criteria for CT application in ED patient complaints. ACR and ACEP should develop collaborative clinical decision recommendations for CT in emergency medicine.

2.       Organizations, such as ACR and ACEP, should develop collaborative educational efforts for emergency physicians and radiologists, including presentations at scientific meetings, joint articles and training and instruction.

3.       Emphasize the “as low as reasonably achievable” principle and EMTALA requirements in educational programs.

4.       Promote skills and processes required for alternate modalities such as x-ray and ultrasound.

5.       Communicate concerns about CT overutilization to hospitals and promote protocols to reduce variability in the ED.

6.       Communicate the importance of clinician-developed decision rules to regulatory agencies and stress the significance of relative indemnification when following these rules.

7.       Develop reliable mechanisms to record the number of CT studies and doses for ED patients.

8.       Develop and adopt protocols to modulate risks to pediatric patients, such as those advocated in the Image Gently campaign.

9.       Develop evidence-based guidelines that address the benefits of CT in emergency medicine.