Although ultrasound imaging technology has been utilized in the emergency room, surgical suites and at the bedside in intensive care units (ICUs) for many years, it's only recently that this use of imaging technology has been referred to as "point-of-care ultrasound imaging".

Dramatic reductions in both the size and cost of ultrasound imaging (US) systems as well as recognition of the technology's clinical value have contributed to rapid growth in the use of point-of-care (POC) US. This trend is gaining the attention of imaging professionals as well as a large and growing number of non-traditional users.

The ability to quickly diagnose a pericardial effusion, internal bleeding or an ectopic pregnancy using a compact US scanner has obvious advantages, but this use of sonography, like many disruptive innovations, is also controversial. Radiologists and other imaging professionals are concerned about appropriate use of the technology, the need for adequate education as well as the impact on referral-based US. Care providers such as emergency medicine physicians and anesthesiologists demand and, in fact, deserve the right to employ POC US--but they face issues regarding reimbursement and credentialing.           

Few would dispute the benefits of including POC US during the assessment of trauma patients (on-site at an accident scene or in the emergency department) or at the bedside in an intensive care unit. Proponents of POC US suggest that obtaining an accurate diagnosis more quickly by including US enhances patient management, expedites treatment when indicated and has the potential to decrease costs by reducing the need for additional imaging examinations. The compact US scanners that are typically employed for POC scans are relatively easy to operate and the care providers are usually familiar with the most common entities encountered within their specialty areas. However, there are no standardized competency assessments for individuals performing POC US exams and the low cost of the technology makes it affordable to virtually any medical professional. Therefore, although a compact US scanner can be purchased and utilized for POC assessments, there is no guarantee that the individual performing the exam is utilizing the modality appropriately or has received the prerequisite training.

Who is holding the probe?

Unfortunately, the use of US technology by the unskilled is not new. Historically, the lack of licensure requirements, the safety and the perceived ease of use of US have contributed to its use by many inadequately trained individuals. Poorly performed examinations done by the unskilled puts patients at risk and has adversely impacted the modality's reputation as a reliable diagnostic tool. For more than a decade the American Medical Association has considered the use of US within the scope of practice of any appropriately trained physician (see sidebar). However, what constitutes "appropriately trained" is subject to debate between professional imagers and other practitioners especially when there are economic benefits involved. Turf wars over the use of US have waged for many years. Currently, the extraordinary proliferation of POC US and the potential for adverse outcomes--especially in critical care settings--heightens the concern over the use of POC US by those who may not be qualified.  

Collaborations between medical imaging organizations and POC physician groups have proven effective in improving the use of POC US. In 2010 the American Institute of Ultrasound in Medicine (AIUM) hosted the Ultrasound Practice Forum: Point-of-Care Use of Ultrasound that included representatives from more than 45 medical societies. The focus of the meeting was ".to explore professional issues related to emerging point-of-care ultrasound technologies."  The Forum was the result of the AIUM's recognition that the use of US technology is rapidly expanding in a wide number of POC applications.

Recently the AIUM announced that it now recognizes the American College of Emergency Physicians (ACEP) Policy Statement Emergency Ultrasound Guidelines as meeting the qualifications for performing US in the emergency setting. The ACEP guidelines describe the education and training that is required by emergency department physicians to attain competency for the performance of focused emergency US applications.

Adequate training that includes both appropriateness criteria as well as instruction on the clinical utilization of POC US continues to be a hot topic that is gaining attention around the globe. The World Interactive Network Focused On Critical UltraSound (WINFOCUS) describes itself as "The world leader scientific organization committed to develop point-of-care ultrasound practice, research, education, technology, and networking."   As described on the WINFOCUS web site, "Clinical scenarios turn into 'critical' ones when there is a dangerous performance gap between the patient status and the resources available for decision making and problem solving."  

Furthermore, both for-profit as well as non-profit ultrasound education providers recognize the need to provide training to primary care providers. Programs ranging from a day or two to several weeks in duration are now available. Manufacturers of POC US equipment also promote training to new customers in order to assure responsible and competent use of their systems. Of course these vendors are also interested in increasing their market share and the provision of training courses, especially for physicians who may be reluctant to adopt POC US, is viewed as an added value during the purchase.

Current Trends in Point-of-Care Ultrasound Imaging

In an article in the November issue of the Journal of the American College of Radiology Levin, et al evaluated Medicare Part B databases for the years 2004 to 2009 to determine how many noncardiac POC US studies were performed and which medical specialties were billing for them. They found that over the five-year period there was a 21 percent increase in the number of POC scans done of which radiology-based labs performed 55 percent while 41 percent were done by nonradiologists (the remaining 4 percent were done at freestanding diagnostic testing facilities where  the specialty could not be determined). Over the five-year period, radiologists' utilization rate increased by 17 percent, compared with a 28 percent increase for nonradiologists. The study concluded that although radiologists continue to perform the majority of POC US studies and their market share has remained stable, a number of other specialties are utilizing the modality for POC applications.

As indicated in the paper, one limitation of the study was that the data only included POC US studies in the Medicare data base (i.e., those that were being billed for reimbursement) and did not take into account studies that were performed ".in an informal, nonbilled manner." This likely represents a relatively large number of nonradiologist POC scans, whereas virtually all US studies performed by radiology-based personnel are billed. The authors go on to suggest that their data ".indicate that as of 2009 [POC US] did not seem to be growing rapidly."  This view is likely flawed and, in fact, contradicts most market reports and forecasts.

Advances in US technology continue to evolve leading to ever smaller and easier to use scanners. There are currently several commercially available units that can fit in the palm of the hand and are battery operated. Although these tiny units presently have limited capabilities they can be used for basic clinical assessments and are now being used as a replacement for the ubiquitous stethoscope. It will be interesting to see how these "sonoscopes" are incorporated into medical practice in the future. Most medical schools now include significantly more US education than in the past.

 To Bill or Not to Bill

Reimbursement is another unresolved issue surrounding POC US. As mentioned previously, in many instances US studies that are provided at the POC are performed to address a very specific question (e.g., Does the patient have a pericardial effusion?) in order to expedite triage or guide management. There are several requirements to obtain reimbursement. The practitioner must provide a written report that describes the indication for the scan, the anatomy evaluated and an interpretation of findings. Additionally, US images must be included as a permanent record and some third-party payors restrict reimbursement to providers who demonstrate specific levels of training or have appropriate credentials. When a physician utilizes US to "take a quick look" the limited time and resources used may not justify the burden involved in obtaining reimbursement (i.e., its just not worth the trouble).

Point-of-care US is rapidly being viewed as an important advance in a wide number of medical specialties. As US technology becomes increasingly more affordable, smaller and easier to use we can expect that it's use will become even more common. How POC US ultimately impacts the use of traditional sonography performed on a referral basis remains to be seen.

Daniel A. Merton, BS, RDMS, FSDMS, FAIUM, is the technical coordinator of research at the Jefferson Ultrasound Research and Education Institute, Department of Radiology, Thomas Jefferson University Hospital in Philadelphia.