Erik Ridley’s article in AuntMinnie discusses the research presented by investigators from the ACR's Harvey L. Neiman Health Policy Institute at the American College of Radiology (ACR) meeting (May 2017) in Washington, DC.1 The e-poster presented at the meeting compared downstream imaging utilization after emergency department ultrasound examinations interpreted by radiologists versus non-radiologists.
To answer the question posed in the title: Who should read point-of-care ED ultrasound exams? The answer is simple and clear: emergency medicine physicians who are performing these studies bedside. In fact, this stems back to the 1999 American Medical Association House of Delegates Resolution, which affirmed that ultrasound is within the scope of practice of all appropriately trained physicians, and all medical specialties have the right to use ultrasound in accordance with educational standards developed by their own specialty. For almost two decades, emergency physicians have been performing and interpreting POCUS studies at the patient’s bedside. Real-time ultrasound interpretations are contemporaneously incorporated into medical decision making at bedside. Radiology reads are not compatible with this model of practice.
Furthermore, this brings into discussion the skill set of the two very different specialties. The Emergency physician is performing POCUS studies with which radiologists have limited experience. Radiologists do not perform and/or interpret lung ultrasound, cardiac ultrasound, ocular ultrasound, and a number of other POCUS applications.
Every institution has a different culture, but we are certain the radiologists at any institution would not want to take on the incredible task of reading over 5000 POCUS studies performed annually. Another institution-dependent point is frequently that a POCUS study with significant or “positive” findings often yields a “consultative” study by radiology. This is not due to uncertainty on the part of the EM physician or lack of confidence, but rather, it is institutional culture. Furthermore, a follow-up radiology study after a POCUS study could be due to a multitude of reasons other than interpretation uncertainty. With the ability to assess the patient at bedside, emergency physicians may order further imaging due to changes in patient symptoms, recurrence/persistence of symptoms, requests by consultants or admitting services or the need for a more comprehensive examination during their inpatient stay. An example might be a comprehensive echocardiogram in addition to the limited cardiac ultrasound exam performed during the initial assessment in the ED. Another example is the frequent follow-up CT to a bedside FAST exam in trauma patients to rule out various injuries that FAST exams are not intended to diagnose. There are also innumerable instances of initial radiology ultrasound reads followed by CT or MRI.
This study done by Carroll et al has several methodological limitations. The data shown by Dr. Van Carroll’s team is not meaningful to changing clinical practices because the Medicare database reveals no associated information on patient outcomes. It is unclear on what “additional imaging studies” means, whether it be another POCUS study, radiology “consultative” ultrasound, x-ray, CT or MRI.
Both specialties have a vested interest in providing the best patient care with the least cost. Although the Ridley article and the Carroll et al study attempt to shed light on the imaging cost component of patient care, they fail to consider the environment in which POCUS are being performed and the impact they have on immediate medical decision making. It is imprudent and incorrect to evaluate the role of POCUS in a radiology-centric context.