Simulation-based training in ultrasound-guided regional anaesthesia for emergency physicians: insights from an Italian pre/post intervention study

Abstract

Background

Despite the importance of Ultrasound-guided Regional Anaesthesia (UGRA) in Emergency Medicine (EM), there is significant variability in UGRA training among emergency physicians. We recently developed a one-day (8 h), simulation-based UGRA course, specifically tailored to help emergency physicians to integrate these skills into their clinical practice.

Methods

In this pre/post intervention study, emergency physicians attended a course consisting of a 4-hour teaching on background knowledge and a practical part structured as follows: a scanning session on a healthy individual; a needling station with an ex-vivo model (turkey thighs); a simulation-based learning experience on local anaesthetic toxicity (LAST); a session on the UGRA simulator BlockSim™. Participants rated their level of knowledge across several domains of UGRA practice; for this purpose, we used a 5-points Likert scale (from 0 to 4). Participants also rated the perceived utility of the practical sessions. We extrapolated baseline characteristics of participants, and we paired the answers of pre- and post-course questionnaires using Wilcoxon signed-rank test.

Results

Seventy-four emergency physicians across ten Italian regions and Switzerland completed the pre-and post- course questionnaire. Most of them were EM residents (75.68%) who had never performed UGRA. Median self-reported knowledge significantly improved from 1 to 3 in the following domains of UGRA indications: Knowledge of contraindications and UGRA techniques [pre-course 1 (IQR 1–2), post-course 3 (IQR 2–3)]; Equipment and drugs [pre-course 1(IQR 1–1), post-course 3 (IQR2-3)]; LAST recognition [pre-course 1 (IQR 1–2), post-course 3 (IQR 2–4)]; LAST management [pre-course 1 (IQR 1–1,75), post-course 3 (IQR 2–3)] (p < 0.001). A smaller improvement was observed in the domain Knowledge of “sonoanatomy” (from 1 to 2; p < 0.001); this might be due to the fact that a one-hour scanning session on a single healthy volunteer may be insufficient for learners to gain confidence with the relevant sonoanatomy. Most participants rated positively the utility of practical stations (100% for the scanning session; 100% for the ex-vivo station with turkey thigh; 91.8% for the BlockSim™).

Limitations

The main limitation of this study is that measurements are limited to learners’ reaction to learning and self-assessment outcomes. We did not measure the impact of our course on participants’ performance in simulated settings, or on their behavior in the clinical setting, or on patient outcomes. The sample size of participants was relatively small, although larger than most published similar studies.

Conclusions

This one-day simulation-based, UGRA course tailored for emergency physicians led to improved participants’ self-reported knowledge across several domains of UGRA practice. The course represents an effective educational strategy and can be replicated in other settings for the initial training of emergency physicians in UGRA.

Background

In recent years, Ultrasound Guided Regional Anaesthesia (UGRA) has become a core component of emergency medicine (EM) practice. The effectiveness of UGRA approaches in the Emergency Departments (EDs) has been demonstrated for many clinical scenarios. In fact, in addition to the well-established role in providing analgesia for muscoloskeletal injuries or as an alternative to procedural sedation for painful procedures, in recent years their use has expanded to include innovative applications like the treatment of visceral pain and ventricular arrhythmia [1,2,3,4,5,6,7,8,9,10].

In 2021 the American College of Emergency Physicians (ACEP) released a policy statement according to which UGRA is “not only within the scope of the practice of emergency physicians but represents a core component of a multimodal pathway to control pain for patients in the ED” [11]. Despite the acknowledgement of the importance of UGRA in EM practice, high variability exists in the training of emergency physicians [12, 13], although a consensus of experts from the United States has recently proposed a standardized curriculum [14]. In a survey conducted in 2016 among academic institutions with emergency medicine residency training programs in the United States, 53% of programs included UGRA in the ultrasound core content, while 30% provided this education during elective time. The majority of UGRA education was delivered through hands‐on training and didactics (73% and 69% respectively), with a combined approach being most common among programs. 13% of programs had other ways of incorporating UGRA training, which varied from procedure labs, grand rounds, or interdepartmental conferences with anesthesia [13].

A similar survey conducted in the same year confirms a substantial variation in the development of protocols and policies for the use of UGRA in the ED, the type of nerve blocks used and the frequency of use and, most of all, a lack in standardization about education and effective training strategies (of both EM residents and fellows) [2]. This high variability in training is in contrast to what happens in the field of anesthesia, where basic UGRA teaching is well standardized [15] and opportunities for structured advanced training - including certifications from international UGRA societies – are established.

Various educational modalities have been proposed to teach UGRA, from short workshops to longer didactic sessions and simulation techniques [16]. It is known that simulation-based training in health care is generally associated with small to moderate effects when compared with non-simulation instructional approaches, such as lectures [17, 18]. A systematic review on the topic suggests that simulation-enhanced UGRA teaching improves knowledge acquisition with this specific skill set, although authors could not make any specific recommendation about the type of simulation modality to be utilized (e.g., robotic and static mannequins, partial task trainers, cadavers, live animals or animal parts, and computer-based virtual reality simulators, etc.) [16]. In contrast to other countries, like the United States, where UGRA teaching has been fully integrated into emergency medicine curricula, Italian emergency physicians are not routinely trained in UGRA. Moreover, publications on UGRA from the Italian emergency medicine community are scarce, which may suggest underutilization of these approaches in our national context.

To reduce this educational gap, our research group (RAEM - Regional Anaesthesia in Emergency Medicine) has recently developed a one-day (8 h), simulation-based, UGRA course specifically tailored to help emergency physicians integrate these skills into their clinical practice.

The scope of this study is to describe the effect of the course on participant’s self-reported knowledge across several domains of UGRA practice, assessed through a questionnaire administered pre- and post-course.

Methods

Course structure

The course begins with a 4-hour mix of frontal lessons and clinical cases presentation, which cover the basic principles of UGRA practice:

• Fundamentals: scope of practice, multimodal analgesia, single shot versus continuous block, anaesthetic versus analgesic block, anaesthetic drugs, adjuvants, equipment, peripheral nerve stimulation, sonographic appearance of nerve structures, two operator’s technique.

• Safety in UGRA practice: alternatives to nerve block, local anaesthetic choice and dose calculation, patient monitoring, “stop before you block” step, infection prevention, aspiration, pressure monitoring during injection, closed-loop communication between first and second operator, prevention strategies and early detection of local anaesthetic toxicity syndrome and nerve injury [19,20,21].

• Main techniques and Indications (specific to currently available evidence in EM practice).

• General and block-specific contraindications (e.g., blocking limbs at risk of developing compartment syndrome).

• Management of complications: local anaesthetic toxicity (LAST) syndrome and nerve injury [22, 23].

The course covered the following UGRA techniques:

• Upper extremities: interscalene and supraclavicular approaches to the brachial plexus, forearm nerve blocks.

• Chest wall: serratus anterior plane block and erector spinae plane (ESP) block.

• Lower extremities: suprainguinal and infrainguinal fascia iliaca nerve block, pericapsular nerve group (PENG) block, femoral nerve block and popliteal sciatic nerve block.

• Neuromodulation in refractory ventricular arrhythmias: left-sided stellate ganglion block.

The theoretical content delivered is generally based on the consensus curriculum developed in 2021 [14]. However, we included some techniques that are not recommended in the curriculum, specifically ESP block and stellate ganglion block. In fact, since the publication of the consensus curriculum, growing evidence supporting the effectiveness of these approaches in the emergency setting has emerged [5, 8,9,10].

Following the morning theoretical session, participants rotate through four different stations for hands-on, simulation-based training (4 h in total):

• A scanning session on healthy individuals, during which the participants learn and practise the relevant sonoanatomy of the UGRA techniques described above (Fig. 1-A). The anatomical structures to be identified for each nerve block are those recommended in a recent consensus paper [24]. In addition to that, participants also learn about patient positioning and the setup of ultrasound machines.

For this station we used either an ESAOTE MyLab or SAMSUNG SonoScape machines, with linear (3–22 MHz) or curvilinear probe (1-5 MHz).

• A needling station using an ex-vivo model (turkey thigh) to train needle-probe coordination, hydro dissection of the fascial plane, and two-operators technique including closed-loop communication between first and second operator (Fig. 1-B).

For this station we used a Fujiflm Sonosite M Turbo machine with a linear probe, normal saline or water, and ad-hoc block needles.

• A simulation-based learning experience on local anaesthetic systemic toxicity (LAST) management, using the mannequin HAL® S3201 (Gaumard) and an actor giving voice to the mannequin (Fig. 1-C). The simulation was structured as follow: a familiarisation phase with the manikins and the setting, a play phase and a debriefing phase. The debriefing phase, in turn, was characterised by a defusing phase, a descriptive phase, an in-depth phase and take-home messages. We created a checklist to investigate technical (e.g. choice of the most appropriate nerve block, LAST recognition and management) and non technical skills (e.g. teamworking). A detailed description of this scenario can be found in a previous published work of our group [25].

• A simulation session with BlockSim™ (Accurate Solutions srl) (Fig. 1-D). BlockSim™ is a high-fidelity simulator for ultrasound-guided interfascial blocks and peripheral nerve blocks. This simulator allows visualization of the needle tip as it passes through tissue, confirmation of alignment with the desired path, and continuous visualization of the administration of local anaesthetic solution. It is equipped with three ultra-durable tissue inserts that include traditional anatomical landmarks and fascia layers, which provide precise tactile feedback to the user while inserting the needle, as well as the feel of the typical fascial “pops”. The user can practice and develop competency using simulation scenarios based on real clinical images.

Fig. 1

Practical sessions of the course. A: scanning session on healthy individuals; B: needling station using an ex-vivo model (turkey thigh) C: simulation-based learning experience on LAST management D: nerve block simulator BlockSim™

The course was designed and developed by SDP, an EM consultant with clinical and research interest in UGRA. FR and BB drafted the work, contributed to the conception and design of the work; SP, FS and VM revised critically the work for important intellectual content. VA (EM resident), DL and AZ (clinical toxicologists) designed the simulation-based learning experience on LAST. A group of EM residents (EL, AS, ASD, CEC, ER) and medical graduates (RM, PD), all trained as facilitators in simulation and with interest in UGRA, supported teaching both in the theoretical and practical sessions. SS, EB (consultant cardiologists) and EC (consultant in pre-hospital emergency care) provided lectures on left stellate ganglion block for the treatment of arrhythmic storm, as they have specific clinical and research interest on the use of this technique.

Study design

We evaluated participant’s baseline characteristics, including demographics, year of specialty, level of expertise in UGRA, and their self-reported knowledge across several domains of UGRA practice via pre-course and post-course anonymous questionnaires (see Supplementary material). Questionnaires consisted of multiple questions where participants had to rate their level of knowledge about indications, contraindication, materials, execution technique, ultrasound anatomy, recognition, and management of complications using a Likert 5-points scale (0 = I have no knowledge on the topic, 1 = insufficient knowledge, 2 = sufficient knowledge, 3 = good knowledge, 4 = excellent knowledge). In the post-course questionnaire, participants also rated the perceived usefulness of the lectures and of each practical session using the same scale. The post-course questionnaire included a question in which participants rated their perceived impact of the course on their daily clinical practice, using a 4-point scale. To the best of our knowledge, no currently available validated questionnaires would serve for the purpose of our study. Hence, we developed the ad-hoc questionnaire using face and content validity. Construct validaton would require an amount of time and resources equivalent to that of the study itself, pushing it beyond practical feasibility. Data analysed include only a convenience sample of physicians who voluntarily participated in the course. We did not randomise participants to different interventions and we did not compare participants to a control group. Informed consent to participate was obtained from all of the participants in the study.

Statistical analysis

From the questionnaire obtained, descriptive statistics were calculated, including medians and interquartile ranges (IQR). Categorical variables were reported as counts and percentages. We paired participant’s answers of pre- and post-course questionnaires and analyzed data using Wilcoxon signed-rank test. Only complete pairs were included in the analysis, i.e. questionnaires that were completed both before and after the course. Missing data from incomplete pairs (e.g., questionnaires filled only before the course) were deleted, but the baseline characteristics of these responders are presented in the results. We assumed non-normal distribution of paired differences, which was assessed graphically. We tested the null hypothesis (H₀) (the population median of the difference scores = 0) against the alternative hypotheses (H₁ two sided: m ≠ 0;

H₁ right sided: m > 0; H₁ left sided: m < 0). W statistics were calculated and compared to critical values from reference table for significance. Data were elaborated with Microsoft Excel 2022 (Microsoft Corporation, Redmond, WA).”

Results

Seventy-six emergency physicians attended the course, which took place in different editions in Bologna, Pavia, and Parma (Italy) between September 2022 and January 2023.

Two of them did not complete the post-course questionnaire, so the data of seventy-four participants were analysed. Baseline characteristics of the excluded participants were similar to those of participants included in the analyses, in terms of demographics and background competencies. In particular, both individuals were EM trainees and reported no previous exposure to UGRA.

Participants were emergency physicians practicing in ten different Italian regions, with a small representation of physicians from Switzerland, as detailed in Table 1.

Table 1 Geographic distribution of participants

Their baseline characteristics, including demographics, level of training and pre-course competence in UGRA are summarised in Table 2.

Table 2 Participants baseline characteristics

Among the eighteen participants who reported having already performed nerve blocks prior to attending the course, three (16.66%) had performed upper extremities blocks (axillary nerve block n = 2, forearm nerve block n = 1). Sixteen participants (88.88%) had performed chest wall or abdominal wall blocks (serratus anterior plane block n = 10; ESP block n = 2; TAP block n = 3; intercostal nerve block n = 1). Twelve participants (66.66%) had performed lower extremities blocks (fascia iliaca nerve block n = 2; PENG block n = 3; femoral nerve block n = 5; popliteal sciatic nerve block n = 1; lower limb-unspecified n = 1). One participant had performed occipital nerve block.

Scores of self-reported knowledges in the pre- and post-course questionnaires are detailed in Table 3. Although during practical sessions we assessed participants by direct observation and we provided real-time verbal feedback, objective measurements of skills’ proficiency were not obtained.

Table 3 Scores of pre-post course questionnaires

We asked participants to rate the utility of the scanning session, of the needling station with an ex-vivo model and of the BlockSim™ simulator using a 5-point Likert scale. Their ratings are detailed in Fig. 2.

Fig. 2

The pie charts describe participants’ perceived utility of three of the four training sessions. Possible scores were “useless”, “poorly useful”, “moderately useful”, “very useful”, and “extremely useful”

We did not perform a formal qualitative assessment of participants’ feedback. Nevertheless, we found their oral feedback very useful during the practical session, as they provided many important suggestions on how to implement the course (e.g., “it would be better to scan several healthy volunteers rather than only one to have a better understanding of sonoanatomy”; “using the turkey thigh is a great way to train needling and fascial plane hydrodissection”; etc.).

Sixty-nine participants (93.24%) reported that this course will affect the daily clinical practice from “enough” to “greatly” (“enough”: n = 43, 58.1%; “greatly”: n = 26, 35.14%), whereas only a few participants reported it will have a negligible impact on their daily clinical practice (“no influence on my clinical practice”: n = 0, 0%; “little influence on my clinical practice”: n = 4, 5.4%,). One participant (1.35%) didn’t answer this single question.

Discussion

As the evidence supporting UGRA applications in EM practice grow at rapid pace, defining which set of skills and competencies emergency physicians should acquire – and how they should develop them - is a priority for scientific societies and educators. In recent years, our research group identified the need to implement UGRA education for Italian EM trainees and practicing emergency physicians, as we noticed that this important area of expertise was rarely taught in our national residency programs. We therefore set up a course that incorporates teaching of background knowledge - largely based on the UGRA Curriculum for emergency medicine by Tucker et al. [14]- and simulation-based learning. Based on our findings, the course led to a significant improvement in participants’ self-reported knowledge across all domains of knowledge. The improvement in “Knowledge of sonoanatomy” was modest, although most participants found the sonoanatomy training useful. This probably suggests that more time is required for learners to gain confidence with the relevant sonoanatomy, and that the one-hour scanning session on a healthy volunteer is perceived as insufficient. In future courses, we could improve this by dedicating more time to this session and by letting participants scan more than one volunteer. In our opinion, this could lead to better recognition and more confidence with anatomical variants that will be faced in clinical practice. Participants particularly appreciated the needling station with an ex-vivo model (turkey thigh), which enables training on needle-probe coordination and hydro dissection of fascial planes. Being a low-cost solution, it can easily be replicated in other settings with limited resources, similarly to other ex-vivo models that have already been described [26].

We did not ask participants to rate the utility of the simulation-based learning experience with the mannequin HAL® S3201 (Gaumard), but they self-reported their “knowledge of LAST management” which significantly improved post-course. Being LAST a high-acuity, low-occurrence event, it lands itself well to simulation-based learning. We adopted a high-fidelity mannequin and immersive reality, but less expensive alternatives could be used (e.g., basic life support mannequins). The availability of a checklist during a stressful event like LAST can improve physician’s performance by supporting them with a stepwise approach of drug selection, avoiding reliance on memory [22, 25, 27]. We therefore provide this costless tool during the scenario and highlight to participants the importance of adopting it in their clinical setting [25]. The majority of participants appreciated the BlockSim™, although some criticized what was the main limitation of the former version of the simulator, i.e., the inability to re-adjust needle’s trajectory after the needle has passed the skin. Based on participants’ feedback the manufacturing company has now implemented this function to make the simulation of fascial plane and nerve blocks even more realistic. In general, the major advantage of the simulator is that physicians can train the sonoanatomy and motor skills of several procedures before attempting them on patients for the first time. This could improve block success in the clinical setting and help educators pre-assess the level of competence of learners to determine whether they are ready to start practicing UGRA on patients.

Eventually, for what concerns the background knowledge, we believe that some nerve blocks not recommended in the curriculum by Tucker et al. – namely PENG block, ESP block and stellate ganglion block - are particularly relevant for EM practice and we therefore included them in our course, based on recent evidences that were not available at the time the curriculum was developed [5, 8,9,10]. The consensus of experts also considered outside the scope of an introductory curriculum all elements of the “Institutional factors” and “Interdepartmental politics” [14]. However, we know that some colleagues will experience in their local context a lack of support by hospital leadership or even resistance against the implementation of UGRA practice. This could be particularly true in Italy where EM is a relatively young specialty, or in other European countries, where it does not even formally exist yet, as compared to the United States where EM training is more uniformly structured, and the scope of practice more clearly defined. Therefore, we highlight the importance of involving local opinion leaders and establishing structured training pathways for emergency physicians (e.g., attending operating rooms to gain proficiency under anaesthetic supervision). Moreover, it is essential to frame UGRA practice within specific pathways (e.g., hip fracture pathway) that should be well defined and agreed by a multidisciplinary team across the hospital (e.g., ED team, orthopedics and anaesthetists for hip fracture pathways). In general, many barriers can be encountered against the implementation of UGRA practice in ED setting, and no “magic bullet” exists to solve this issue. Instead, all tools offered by implementation science should be used to overcome barriers and let patients benefit from UGRA application in the emergency setting. We therefore always conclude our course with a brief “tips and tricks” discussion, where we provide suggestions on how to deal with “political dramas” that may arise during the implementation of UGRA practice, and how to build constructive interdepartmental cooperation.

Limitations

Although almost all participants stated that this course will positively affect their everyday clinical practice, we do not know whether this will occur or not.

In fact, the main limitation of this study is that measurements are limited to learners’ reaction to learning and self-assessment outcomes, corresponding to Kirkpatrick level 1 [16]. We did not measure the impact of our course on participants’ performance in simulated setting, or on their behavior in the clinical setting, or on patient outcomes. This should be assessed in future studies.

The sample size of participants was relatively small, although larger than most published similar studies. In addition to that, the wide geographical distribution of participants should be regarded as a strength of the study. In fact, they represented many Italian regions and part of Switzerland, thus increasing the generalizability of the study results at least at a national level.

Conclusions

Our one-day (8 h), simulation-based, UGRA course specifically tailored for emergency physicians led to improved participant’s self-reported knowledge across several domains of UGRA practice. All stations - including a needling station with turkey thigh, a simulation-based learning experience on LAST, a scanning session on the UGRA simulator BlockSim™ and a scanning session on a healthy individual – were considered of high utility by participants. Our findings suggest that a one-hour scanning session on a single healthy volunteer may be insufficient for learners to gain confidence with the relevant sonoanatomy.