Incorporating Training in POCUS in Nephrology Fellowship Curriculum

Point-of-care ultrasound (POCUS) is an emerging core competency in nephrology (1). Indeed, discussion is ongoing about whether to add core POCUS competencies to the Accreditation Council for Graduate Medical Education (ACGME) requirements for nephrology training programs. In this issue of CJASN, Moore et al. (2) present data from a national survey of nephrology fellows and training program directors on training in POCUS. They demonstrate the existence of established POCUS education in a substantial portion of nephrology training programs and the desire on the part of the vast majority of fellows and training program directors to expand learning opportunities in this sector. However, the article highlights limitations, particularly the dearth of POCUS-trained faculty, which underscores the need for faculty development and protected time for curriculum development and one-on-one instruction.

POCUS consists of limited ultrasound studies performed at the bedside by the provider and is meant to answer focused, closed-ended questions with binary—yes or no—answers. In nephrology, POCUS is used to quickly exclude obstructive uropathy, evaluate hemodynamics and volume status, evaluate for pulmonary congestion or pleural effusions, and evaluate maturation and guide cannulation of the hemodialysis vascular access (3,4) (Figure 1). POCUS stands in contrast to comprehensive kidney ultrasonography that is practiced by some nephrologists, which is meant to represent a full investigation of the system, replacing radiology-performed studies. Limited POCUS studies do not obviate the need for comprehensive radiology studies. Advantages of POCUS include defragmentation and expedition of care. Further, POCUS draws the provider back to the bedside, providing more time for patient interaction, and enhances patient satisfaction. POCUS represents a potentially untapped revenue source, with some providers billing for limited studies (5). The burden of documentation is low, and medicolegal concerns are often overstated (6).

Figure 1.

Nephrology-related point-of-care ultrasonography (POCUS) applications. (A) Basic applications are represented in gray, advanced/Doppler applications are in red, and procedural guidance is in blue. (B) Building blocks of a POCUS program. Kidney and bladder icons were obtained from Biorender. FOAMed, free open access medical education (e.g., social media and educational blogs); IJ, internal jugular; IVC, inferior vena cava; US, ultrasound.

The act of teaching POCUS in nephrology is distinct from other domains of kidney medicine. Learning POCUS combines both psychomotor learning for performing and fine-tuning the scan and cognitive learning for visual pattern recognition for recognition of normal versus pathologic states. Like learning a language, taking up POCUS requires an intensive immersive experience coupled with longitudinal maintenance learning to keep up the skill. For many learners, the cultivation of the psychomotor aspects of image acquisition requires one-on-one hands-on learning, putting pressure on already busy academic clinicians, particularly at centers understaffed in trained faculty. It is difficult to estimate how much time is required to achieve a minimum level of competency, and it varies by user. We suggest that fellows have ten scans per POCUS application directly supervised by a POCUS-trained faculty member and judged to be adequate prior to scanning independently. Irrespective of skill level, we recommend 100% quality assurance of learner-derived studies. We suggest a target of 40 adequate scans for each POCUS application for credentialing purposes to conform to other non-nephrology credentialing guidelines, such as those put forward by the American College of Emergency Physicians.

POCUS has been growing in popularity for some time and has been used in every discipline in medicine. POCUS has been the standard of care for many initial diagnostic evaluations in emergency medicine for decades and is an ACGME core competency in critical care medicine. Several factors have driven growth in POCUS, including decreasing cost and increasing portability of ultrasound devices; this was accelerated more recently by the introduction of the capacitive micromachined ultrasonic transducer, which provides an alternative for traditional piezoelectric crystals. Artificial intelligence applications, such as feature recognition and labeling, as well as active user guidance make POCUS more accessible to early learners. Integrated ultrasound telemedicine allows for remote guidance of novice learners by experts physically removed from the place of care, serving as a force multiplier for institutions with few POCUS-trained faculty. Finally, cloud computing has made it easy to fulfill medicolegal and billing requirements for durable image archiving and facilitation of quality assurance. From an evidence-based medicine perspective, limitations of physical examination, particularly in the context of the obesity pandemic, have come into sharp focus. The growing evidence base for certain applications of POCUS has put ultrasound in stark contrast with physical examination signs, which often lack sensitivity, being based more in eminence rather than evidence (7). However, we acknowledge that POCUS, just as with physical examination, is only helpful if performed correctly by the learner and for an indication appropriately evaluable with ultrasound.

The study by Moore et al. (2) comes at the exact right time as more and more nephrology fellowships are building POCUS programs in response to growing demand from nephrology fellows. Moore et al. (2) surveyed fellows and training program directors/associate program directors (TPDs/APDs) using a digital survey instrument. Demographic information was broadly representative of fellows as a whole. Surveys for fellows were performed at the time of the in-service examination with 69% response rate (631 of 912), whereas surveys for TPDs/APDs were performed through an American Society of Nephrology (ASN) flash poll with two email follow-up reminders, achieving a respectable 39% (82 of 229) response rate.

In total, 38% of fellows reported having POCUS education, but only one third of those reported feeling competent in using POCUS independently. Twenty-three percent of TPDs/APDs reported having a POCUS curriculum in place, and 95% of TPDs/APDs who did not currently have a POCUS curriculum in place reported having a POCUS program in development or interest in doing so. Only three TPDs/APDs reported having no interest in building a POCUS curriculum. The biggest barriers to the creation of a program identified were lack of trained faculty (53%), inability to bill for POCUS studies (34%), and lack of access to ultrasound devices (34%).

Limitations of the study are primarily those inherent to survey-based research. Of particular importance is the potential for introducing selection bias, with fellows and faculty potentially being more willing to complete the survey if they were already enthusiastic about POCUS. The large and broadly representative sample ameliorates this concern to some extent. Next, what constitutes the definition of an “established curriculum” among training programs is not defined in the survey instrument and could range from a few lectures to a comprehensive and fully integrated program complete with objective clinical skills assessment. Finally and much to our consternation, the survey left out what we consider a major branch of POCUS in nephrology: hemodynamic monitoring with more advanced tools, including venous excess ultrasound—direct measurement of venous congestion interpreted using Doppler waveforms of intra-abdominal veins—a subject that has garnered a lot of interest in recent years particularly from trainees and has a growing evidence base (8).

Whether you are a POCUS aficionado or are a recalcitrant skeptic, there is no denying the simple facts. POCUS is standard of care across multiple disciplines, is being taught to virtually all medical students and internal medicine residents, and is one of the most desired skills among nephrology trainees. Training programs need to be prepared regardless of whether POCUS is named a core competency by ACGME, or they risk being selected against by a pool of nephrology fellowship applicants inadequate to fill all programs. This means prioritizing POCUS curriculum development and provisioning the resources needed to make it happen.

The groundwork has been laid with a robust network of free, open access medical education resources with off-the-shelf POCUS curricula ready for implementation (9). For training faculty, immersive POCUS courses exist at major nephrology scientific meetings. A 2-day course with a hybrid format and 8 hours of hands-on time is planned at ASN’s Kidney Week this year. One-year POCUS fellowships exist with training in research and education methods as well as POCUS techniques to build the next generation of thought leaders in POCUS in nephrology (10).

Despite all this, gaps remain. Nephrology training programs need to invest in faculty development, with intensive training for faculty POCUS mentors and protected time to provide one-on-one hands-on training for fellows. Noncore POCUS faculty members need basic training as well to interpret image adequacy and incorporate POCUS findings into clinical decision making. Investments in ultraportable devices and image-archiving programs are critical to provide access for fellows while maintaining medicolegal and privacy policy compliant. Scientific societies need to step forward to outline pathways for POCUS accreditation in nephrology, not just for interpretation of kidney ultrasound. Finally, research is needed to ascertain the best teaching methods and to elucidate billing mechanisms so that POCUS programs can move toward revenue neutrality.

Disclosures

A. Koratala reports honoraria from Echonous, Inc. and Vave Health, Inc. The remaining author has nothing to disclose.

Funding

None.

Author Contributions

A. Koratala and N.C. Reisinger wrote the original draft and reviewed and edited the manuscript.