Educational standards for training paramedics in ultrasound: a scoping review

The modern-day Emergency Medical Services (EMS) system is a complex network of coordinated services. Due to the challenging environment and ever-changing nature of work encountered by paramedics, the profession is continually expanding to include a greater range of clinical skills [1]. For example, recent advances have included the addition of point-of-care ultrasound (POCUS) to assist with improved patient outcomes, clinical decision making and triage [2‐4]. Balancing over-triage and under-triage is important for the health-care system as a whole and the patient as an individual [5]. Clinical diagnoses alone are often insufficiently sensitive, leading to misdiagnoses and under-triage of some clinical conditions. In the out-of-hospital setting POCUS can provide additional information, such as earlier detection of intra-abdominal free fluid in patients with blunt trauma, and pericardial effusion in patients with penetrating thoracic trauma [2, 3]. This information can assist with management strategies, guide transport to the most appropriate facility, and potentially expedite time to definitive intervention [3].

Clinical applications of POCUS in the out-of-hospital setting include enhancing assessment of a wide range of patient cohorts, including but not limited to medical and traumatic patients [2]. For example, the Focused Assessment Sonography for Trauma (FAST) exam is used to detect free fluid in the intra-abdominal compartment [4]. The application of FAST by paramedics, emergency physicians and flight nurses has been reported with greater sensitivity and specificity, compared to physical assessment alone, when assessing for hemoperitoneum in patients with penetrating and blunt trauma [6, 7].

Moreover, the extended FAST examination (eFAST) also includes thoracic assessment to detect for haemothorax and pneumothorax [8]. This is a time effective procedure particularly when faced with the challenges of auscultating breath sounds in the out-of-hospital environment, such as in a moving ambulance or during aeromedical transport. A diagnostic accuracy of over 90% when using POCUS to assess for pneumothorax has been reported, suggesting POCUS may be superior to other clinical assessment tools [8]. Correct identification of the presence or absence of pneumothoraces can help guide urgent interventions during resuscitation. Alternatively, this may also prevent unnecessary procedures such as pleural decompression thereby avoiding an invasive procedure that carries potential complications [9, 10]. Other applications of POCUS performed by paramedics include modified cardiac echocardiography to assess for pericardial fluid and tamponade physiology in the setting of trauma and assessing intra-arrest cardiac wall motion [2, 3].

The ability to accurately perform and interpret sonography is likely dependent on appropriate training and education of paramedics [2]. General paramedic training can vary considerably, from vocational based-training through to formal tertiary education at the postgraduate level. With regard to demonstrating competence in POCUS, dependence on background education appears most apparent in EMS systems that use non-physician providers, including paramedics and nurses [2]. Most studies report on EMS providers from a range of clinical backgrounds, and evidence pertaining to the clinical utility of paramedic use of POCUS is limited. A systematic review identified multiple training programs with various delivery methods, duration, and assessment [9]. Similarly, El Sayed et al. [2] and Nelson et al. [4] also discussed POCUS curricula for EMS providers in the out-of-hospital setting. These reviews report POCUS to be feasible and time effective with successful application. However, variations in training duration, and the quality of POCUS examinations by different providers are yet to be compared [4]. Presently, it appears there is no agreed curricula standards for the training of paramedics in the provision of out-of-hospital POCUS, making it difficult to draw conclusions regarding the optimal training approach for paramedics.

With the increasing use of out-of-hospital POCUS to assess a number of clinical conditions, it is important to gauge the different methods by which POCUS is currently being taught to paramedics. This will guide which methods suit various EMS agencies with regards to affordability, applicability, and effectiveness. This scoping review aims to explore the different educational approaches used for training paramedics in POCUS in the out-of-hospital setting.

We desired to map the available literature relating to paramedics and POCUS education. We therefore chose a scoping review methodology in order to provide a broader understanding of this topic, which can then be narrowed down to a specific research question and systematic review [11, 12]. In accordance with scoping review practice we included both peer- and non-peer reviewed research, as well as grey literature [12]. We followed the six stage methodology developed by Levac et al. (2010) [12].

The initial search yielded 2002 de-duplicated articles. The titles of the relevant articles were screened for inclusion, and 1,984 were excluded as per the study protocol, see Fig. 1. The final inclusion consisted of 18 articles. Characteristics of the included studies are provided in Table 2 and the educational details of each study is provided in Table 3.

Ultrasound is a relatively new and emerging assessment modality in out-of-hospital care, especially for paramedics. Technology has progressed to the point where small hand-held devices are readily available for out-of-hospital use. This scoping review examined 18 articles to describe the different curricula used for training paramedics in POCUS in the out-of-hospital setting.

The professional backgrounds of participants undergoing out-of-hospital POCUS training varies. Most studies reported on combined cohorts of physicians, nurses and paramedics all with varying years of experience. Knowledge of gross and functional anatomy can vary significantly, dependent on individual professional background (if any), and the duration and quality of initial education. Numerous physician-based prehospital services across the developed world have been using prehospital US for many years and are mostly helicopter emergency medical services (HEMS) [29, 30]. Physicians staffing EMS prehospital systems are usually sourced from the specialties of anaesthesia, intensive care and emergency medicine. Thus, these staff will already have undertaken significant education in gross and functional anatomy during undergraduate medical studies, and will likely have at least basic training in POCUS as part of their specialist qualification.

Conversely, paramedic regulation and registration as health professionals varies across the world, and there is no standardised qualification to be termed a paramedic in many jurisdictions [31]. The base qualifications for paramedics working in out-of-hospital systems in developed nations may range from short vocational courses, or undergraduate degrees through to postgraduate-level courses. Therefore, it is intuitive that experienced practitioners would gain and achieve competency in a skill dependent on anatomical knowledge more readily than less-experienced colleagues. In this study, paramedics with advanced training and/or extensive experience demonstrated a higher degree of accuracy in POCUS interpretation (where measured) [23]. However, the data available at this time does not show a trend towards a difference between the groups, and a correlation to clinical outcomes is not able to be demonstrated, and is beyond the scope of this study.

This scoping review suggests that the curricula used has varied considerably. Training duration ranged from a short 2-min orientation session to two days with most sessions completed over a one-day course. Of interest, the literature reports POCUS curricula being implemented for physicians as early as the first year of medical school [32]. In one study, Golgalniceanu et al. enrolled third and fifth year students in a 5-h FAST course of which 85% of students completed a full FAST scan at an adequate level of performance in under 6-min [33]. Should further studies demonstrate clear clinical utility of prehospital POCUS, then it may be reasonable to commence basic training in ultrasound during undergraduate paramedic training. Introduction of the skill early in the career of paramedics may strengthen anatomical knowledge, and allow for development of competence in POCUS over an extended period.

Blended learning that integrates face-to-face learning with computer-mediated online components has recently been reported as an effective approach for efficient learning and skill acquisition in POCUS [32, 34]. In this scoping review only two studies included an additional online component [22, 27]. Knapp et al. reported improved post-test scores from 73 to 95% with EMS providers scoring 98.9 to 99.1% on the OSCE stations [22]. This suggests online learning may assist with proficiency in learning the skills and knowledge required for performing POCUS, however is yet to be demonstrated as a superior learning tool. Simulation training for skill acquisition is also well documented in the literature [32, 35]. Interestingly, nine of the studies in this review were performed solely in the classroom on healthy volunteers or cadavers [6, 14‐17, 19, 23, 25, 26]. The remaining studies were performed on ill or injured patients in clinical practice. Further research is required to demonstrate which method provides greater outcomes in regards to clinical education.

At the commencement of training for the various groups, strict protocol for the clinical application of POCUS was not always defined. After training was completed, actual POCUS utilisation varied from FAST, pneumothoraces, cardiac evaluation or a combination of these. The study by Chin et al. was robust in that it followed a strict protocol, although that protocol was limited to only cardiac and lung ultrasound [16]. Nevertheless, adhering to a structured, measured and comprehensive training program, and then instituting a systematic protocol for in-field application of POCUS allowed for ready analysis of outcomes. These inconsistencies may translate to difficulty in assessing clinical utility of out-of-hospital POCUS, but also how proficient paramedics were in interpreting images, and advancing their psychomotor skills.

Paramedic interpretation of ultrasound images in most studies was “confirmed” by US experts. However, in one study, there was no “closing of the loop” with regard to the learning process [18]. Correlation with expert interpretation would seem prudent, given the novel and relatively complex nature of POCUS in the out-of-hospital environment. This highlights the importance of studies examining paramedic education and proficiency in out-of-hospital POCUS which should include assessment of paramedic-acquired images by ultrasound experts, such as sonographers and/or experienced critical care physicians.

Despite various education approaches our review suggests that paramedics may be able to gain proficiency in POCUS reasonably promptly, regardless of base qualification, experience, duration or perceived quality of training. In the study by Quick et al., a small group of paramedics with (on average) greater than ten years’ experience, who underwent a comprehensive education and training program adhered to a strong study protocol and had a high level of patients exposure were able to demonstrate POCUS interpretation accuracy similar to that of trauma surgeons [8]. These data correlate with other studies where paramedics have initiated critical care procedures historically only performed by physicians (in and out-of-hospital) [36]. This suggests that a short duration of education and subsequent continuing clinical exposure (of which a minimum standard is difficult to determine) may be sufficient to enable paramedics to remain proficient in out-of-hospital POCUS. This concept requires further rigorous investigation through well-defined prospective clinical trials.

POCUS curricula for paramedics in the out-of-hospital setting varies considerably. There appears to be no consistent approach, with some systems not quantifying or revising quality of learning. Paramedics with different levels of training and experience appear to be able to gain skills in POCUS, however correlation with clinical utility is difficult to measure. Furthermore, a lack of standardised training and a structured clinical application process makes it difficult to evaluate POCUS as a useful modality in the provision of out-of-hospital care. Further studies investigating education for paramedic POCUS and subsequent clinical application should include a standardised education process, expert assessment of paramedic competency, and formalised protocols for the application of out-of-hospital POCUS, so as to measure clinical utility.