Appropriate use criteria (AUC) have been developed for many conditions and clinical scenarios by medical specialties over the past two decades with the goal of improving the quality, efficiency, and cost-effectiveness of health care. They have been a recent topic of increasing interest to emergency physicians who may be adversely affected by implementation of the Protecting Access to Medicare Act (PAMA) of 2014, which directs the Centers for Medicare and Medicaid Services (CMS) to establish a program to promote use of AUCs for advanced diagnostic imaging services.1 As described by Jay Kaplan, MD, FACEP, and Barbara Tomar, MHA, in their August 2017 ACEP Now article, AUCs may be viewed as “another hoop for emergency physicians to jump through.”
Fortunately, CMS has charged “provider-led entities,” or national professional medical societies and organizations, with developing and endorsing AUCs. When AUCs are developed with proper evidence-based methodology, their use within a clinical decision support system has the potential to reduce inappropriate variation among providers and reduce conflict with consultants. AUCs may also be a powerful tool in managing expectations of patients who present to the emergency department seeking nonemergent imaging studies.
ACEP recently endorsed the Society of Nuclear Medicine and Molecular Imaging’s AUC for ventilation-perfusion (V/Q) imaging in the evaluation of patients with suspected pulmonary embolism (PE).2 Two ACEP members were among 13 experts from multiple specialties who collaborated on the development of the AUC. The workgroup identified 21 clinically relevant scenarios for the use of V/Q scans and provided appropriateness scores for each scenario based on the evidence provided by systematic review of the literature and clinical experience.
The AUC for each of the 21 scenarios were developed using a modified Delphi process. The systematic review was conducted by a group independent of the AUC workgroup to assess the diagnostic accuracy and comparative effectiveness of V/Q scans on clinical decision making and clinical outcomes for acute PE. In addition to the appropriateness scores (see Table 1), the AUC manuscript includes a summary of the existing literature as it pertains to the individual clinical scenarios as well as the conclusions of the workgroup discussions.1 It also highlights the ongoing value of a diagnostic tool that is being used less often due to the increasing availability of computed tomography in emergency departments. For example, to limit the exposure of the mother and fetus to ionizing radiation, a low-dose perfusion-only scan was rated as appropriate (AUC = 9) if the chest radiograph is normal or mildly abnormal.1 AUC scores range from 1 (rarely appropriate) to 9 (appropriate).
Table 1. Examples of AUC scores for V/Q Imaging Most Relevant to Emergency Department Patients
| Clinical Scenario | AUC Score for V/Q |
|---|---|
| Suspicion for PE unlikely, D-dimer negative | 1 |
| Suspicion for PE likely, D-dimer negative | 8 |
| Suspicion for PE unlikely, D-dimer positive | 8 |
| Suspicion for PE likely, patient at risk for contrast complication | 9 |
| Suspicion for PE likely, pregnant patient with normal/mild abnormal chest radiograph, low-dose perfusion scan only | 9 |
Pretest probability of PE determined to be “likely” or “unlikely” based on clinician gestalt or a clinical prediction instrument. AUC score ranges from 1 (rarely appropriate) to 9 (appropriate).
Source: Adapted from J Nucl Med. 2017;58(5):13N-15N.
In summary, emergency physicians should consider AUC for V/Q scans when evaluating patients with suspected PE. Doing so has the potential to decrease variability of care. The implementation of PAMA is inevitable, and other payers who are not using AUCs to assess utilization appropriateness soon will be. ACEP’s involvement in the development and endorsement of additional imaging AUCs relevant to care delivered in the emergency department remains vital.
References
- Protecting Access to Medicare Act of 2014 §218(b,d), 29 USC §1305 note (2014). Promoting evidence-based care. (q) Recognizing appropriate use criteria for certain imaging services. Accessed Sept. 17, 2017.
- Waxman AD, Bajc M, Brown M, et al. Appropriate use criteria for ventilation-perfusion imaging in pulmonary embolism: summary and excerpts. J Nucl Med. 2017;58(5):13N-15N.
Dr. Torbati is associate professor of emergency medicine and co-chairman and medical director of the Ruth and Harry Roman Emergency Department at Cedars-Sinai Medical Center in Los Angeles.
Dr. Brown is professor and chair of emergency medicine at Michigan State University College of Human Medicine in East Lansing.
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