Ultrasound technology as a tool to teach basic concepts of physiology and anatomy in undergraduate and graduate courses: a systematic review.

Many publications describe use of ultrasound imaging in teaching on clinical courses, primarily integrated with clinical applications. More recently there has been increasing numbers of papers describing ultrasound as a tool primarily for teaching basic anatomy and physiology concepts, rather than clinical applications. Of these, many described qualitative analysis with a consensus that its use was viewed very positively by students for aiding learning. Far fewer studies have attempted quantitative analysis to support this belief, and conclusions have been varied. A review of studies was conducted which included those that used ultrasound to teach physiology and anatomy concepts. Studies were excluded if they did not contain quantitative or qualitative assessment of efficacy. Medline and Embase databases were searched (16/11/22) and screened by two independent reviewers. Forty-six studies were included, with data extracted relating to cohort characteristics, ultrasound intervention, quantitative or qualitative assessments and any barriers to implementation. It was confirmed that both student and teacher opinions are extremely favourable in most cases. Although conclusions from quantitative studies were not as clear, there was evidence that ultrasound is at least as effective as more conventional teaching methods and could have significantly better performances in short-term assessments. However, varied methods of teaching intervention, experimental protocols and assessment of learning may have contributed to the lack of clarity. Within this context, some of the problems encountered with implementing ultrasound as an educational tool (such as financial and temporal constraints), and in conducting more definitive studies, are discussed.

Ultrasound skills teaching in UK medical education: A systematic review.

BACKGROUND: Sonography is increasingly integrated into medical curricula to prepare students for clinical practice. In 2022, we conducted a systematic review to explore the degree to which ultrasound skill acquisition is incorporated into undergraduate medial education in the United Kingdom. METHODS: A search of Medline and Embase databases from 2003 to 2022 identified 15 relevant articles. Studies were included if they described ultrasound skills training in UK undergraduate medical education. FINDINGS: A range of teaching methods were reported including didactic demonstrations, hands-on experience and combinations thereof. Portable machines were more common than cart-based machines, and most demonstrators were ultrasound-trained clinicians. Ultrasound teaching is well received, with improvements in confidence using ultrasound, motivation to learn anatomy and retention of knowledge. DISCUSSION: Obstacles to integration were noted including training, cost, curriculum time constraints and the issue of incidental pathology. One study demonstrated that anatomists with appropriate training could provide ultrasound teaching, reducing the need for clinicians or sonographers. Costs may be reduced by renting machines or purchasing portable/hand-held devices. Allowing access to machines during student's free time may address scheduling difficulties. A final recommendation is to pre-scan volunteers prior to the teaching session. CONCLUSION: We have outlined approaches to ultrasound skills teaching and the inherent hurdles to this, as well as potential solutions. This may aid educators wishing to augment their curricula. Although there are relatively few studies from the United Kingdom, there is consensus that students enjoy the incorporation of ultrasound practice and believe it complements existing teaching, especially in a small group setting.

Impact of Peripheral Nerve Block Technique on Incidence of Phrenic Nerve Palsy in Shoulder Surgery.

Peripheral nerve blocks are an increasingly common method of providing postoperative analgesia for shoulder surgeries. However, the standard technique, the interscalene block (ISB), inevitably causes hemidiaphragmatic paresis (HDP), secondary to phrenic nerve palsy. This can cause morbidity in patients with preexisting respiratory compromise, prompting investigation into alternative "phrenic-sparing" nerve blocks. The aim of this review was to give an overview of these blocks and critically evaluate the current literature to determine if any are suitable replacements for ISB. The incidence of HDP and analgesic efficacy were considered. We queried four electronic databases and one register. Twenty-eight original articles were selected for review. The use of ultrasound guidance, lower volumes of local anaesthetic (LA), and injection 4 mm outside the brachial plexus fascia reduced HDP incidence for the ISB; however, no single modification did so sufficiently. While the anterior suprascapular nerve block (SSNB) showed comparable analgesic effects to the ISB, HDP prevalence was also high. The posterior SSNB produced consistently low HDP incidences but also inferior analgesia to ISB, except when combined with an infraclavicular brachial plexus block. The superior trunk block (STB) provided equivalent analgesia to the ISB while reducing HDP incidence, but not significantly. Lower LA volumes consistently led to lower HDP incidence across all blocks, likely due to a reduced ability to spread to the phrenic nerve. Further investigation into the minimum effective volumes of the extrafascial ISB, anterior SSNB, STB, and combined posterior SSNB with infraclavicular block is warranted to determine if any of these blocks can successfully balance HDP prevention with analgesic efficacy.

Bidirectional TRP/L Type Ca2+ Channel/RyR/BKCa Molecular and Functional Signaloplex in Vascular Smooth Muscles.

TRP channels are expressed both in vascular myocytes and endothelial cells, but knowledge of their operational mechanisms in vascular tissue is particularly limited. Here, we show for the first time the biphasic contractile reaction with relaxation followed by a contraction in response to TRPV4 agonist, GSK1016790A, in a rat pulmonary artery preconstricted with phenylephrine. Similar responses were observed both with and without endothelium, and these were abolished by the TRPV4 selective blocker, HC067047, confirming the specific role of TRPV4 in vascular myocytes. Using selective blockers of BKCa and L-type voltage-gated Ca2+ channels (CaL), we found that the relaxation phase was inducted by BKCa activation generating STOCs, while subsequent slowly developing TRPV4-mediated depolarisation activated CaL, producing the second contraction phase. These results are compared to TRPM8 activation using menthol in rat tail artery. Activation of both types of TRP channels produces highly similar changes in membrane potential, namely slow depolarisation with concurrent brief hyperpolarisations due to STOCs. We thus propose a general concept of bidirectional TRP-CaL-RyR-BKCa molecular and functional signaloplex in vascular smooth muscles. Accordingly, both TRPV4 and TRPM8 channels enhance local Ca2+ signals producing STOCs via TRP-RyR-BKCa coupling while simultaneously globally engaging BKCa and CaL channels by altering membrane potential.

Ultrasound imaging in teaching cardiovascular physiology: disruption and challenge to foster learning.

This work extends previously described applications of ultrasound technology in illustrating cardiovascular phenomena to investigation of learning effectiveness. To this end, learning in ultrasound-enhanced classes was assessed by quantifying the improvement in single best answer (SBA) exams conducted before and after an ultrasound practical class. This improvement was then compared to that seen in the same SBA exams conducted in matched groups that undertook similar classes conducted without ultrasound equipment. The SBA exams were designed to include questions that directly related to the phenomena being investigated in the practical classes as well as other "filler" questions to disguise the intent of the exam and ensure that standards of physiology knowledge were similar between the two groups. Any small statistically significant gains in performance observed between the two groups were confounded by differences in baseline (pretest) performance between the groups. These results contradict our previous work, which showed that self-reported measures of learning increased after ultrasound classes. It may be optimistic to expect improvements in deep learning and test performance immediately after even the most effective educational intervention. Direct measurement of the phenomena that bring about deep, long-term learning in classes remains problematic. Notwithstanding this, there is much evidence for the value of enhancing physiology learning by providing varying contexts in the physical, semantic, and cognitive domains. Ultrasound technology is a cheap and effective means of providing such context in physiology practical classes.NEW & NOTEWORTHY This work compares learning in cardiovascular physiology classes enhanced by using cheap ultrasound equipment with learning in comparable control classes without ultrasound. Performance improvement in single best answer tests between pre- and postclass tests were compared for the ultrasound and control classes, with little difference shown between the two classes. We question whether it is appropriate to measure deep learning after 2-h classes or whether other, phenomenological, qualitative measures of educational effectiveness would be better.

Snapshot of ultrasound imaging in basic anatomy and physiology teaching in the United Kingdom and Republic of Ireland: perceptions, obstacles, and solutions.

We have used ultrasound imaging and technology as a tool for nonclinical teaching of basic physiological concepts for several years and are aware anecdotally that only a few others in the United Kingdom and Republic of Ireland (UK/ROI) are also using ultrasound with this intention in physiology and anatomy teaching. To better understand what areas ultrasound is used for by others, along with what barriers might exist to its use, we reached out to colleagues in UK/ROI institutions instructing on anatomy and physiology courses by asking them to complete a survey regarding their experiences. Relatively few institutions (9%) reported using the technology in this way but covered physiology and anatomy teaching in most major body systems. The perception of responding educators overall is that, overwhelmingly, ultrasound offers a useful addition to the teaching of physiology and anatomy and is very popular with students. Barriers to its implementation were identified, including unfamiliarity with equipment and potential uses. Lack of funding for equipment and staff, issues with class sizes, and lack of curriculum time were also identified. Despite these potential impediments, most nonusers were interested in finding out about the uses of ultrasound as a teaching tool. We conclude that the teaching community would benefit from wider dissemination of local practices.NEW & NOTEWORTHY We surveyed UK and Republic of Ireland institutions to establish the extent of ultrasound use in teaching undergraduate modules with significant anatomy or physiology content. Responses indicate that although ultrasound is used for a wide variety of systems, only a small proportion of courses use ultrasound for teaching. There is widespread interest in its use, with the main barriers being unfamiliarity with potential uses and the technology. We endorse further dissemination of this teaching practice.

Brachial artery blood flow by vascular ultrasound in education.

There is extensive and increasing use of ultrasound in medical care and scientific research, so it is important that the technique, indication, and interpretation of ultrasound investigations are included in medical and biological education. Applications of ultrasound in medical care and education employ not only noninvasive imaging of structure but also the evaluation of organ function. Vascular ultrasound is one such application that has been hitherto relatively neglected in physiology education. The techniques of vascular ultrasound and the physiological regulation of human limb blood flow are reviewed to inform students and curriculum designers. Emphasis is placed on the value of converting velocity measurement by ultrasound to volumetric flow and on the mechanisms involved in rapidly changing flows with interventions. Live collection of real data by ultrasound can show macrovascular and microvascular features of vascular physiology. Macrovascular features include imaging and flow velocity profiles. Microvascular perfusion studies show conductance changes with interventions such as exercise and ischemia. Vascular ultrasound offers exciting opportunities for undergraduate research projects using human subjects. The literature is interesting and, though complex, offers excellent educational experience, with scope for the development of critical thinking and meaningful original research.NEW & NOTEWORTHY Ultrasound imaging has emergent prominence in clinical investigation and education. Vascular ultrasound also evaluates function. Simple methods are described that enable the application of basic ultrasound principles to the measurement of velocity and, importantly, to calculate absolute volumetric blood flow. These methods should be useful in undergraduate and graduate education, with application in clinical practice and research.

Feeder-Cell-Free and Serum-Free Expansion of Natural Killer Cells Using Cloudz Microspheres, G-Rex6M, and Human Platelet Lysate.

The versatility of natural killer cells has ignited growing interest in their therapeutic use for cancer and other immunotherapy treatments. However, NK cells compose a small portion of peripheral blood mononuclear cells (5%-20% of PBMCs) and clinical doses require billions of cells. Manufacturing suitable doses of NK cells remains a major challenge for NK immunotherapy. The current standard for expanding NK cells relies on feeder cells and fetal bovine serum to achieve large expansion, but both encounter regulatory concerns. We developed NK Cloudz, a dissolvable polymer-based microsphere platform, as an alternative to a feeder cell approach to expand NK cells. We demonstrated that a combination of NK Cloudz, a G-Rex6M culture vessel, and GMP Human Platelet Lysate expanded NK cells 387 ± 100-fold in 10 days from a PBMC starting population. The NK purity, viability, and cytotoxicity were similar to both a feeder cell protocol and an FBS-based protocol. Additionally, we found no significant differences between FBS and GMP Human Platelet Lysate and concluded that platelet lysate is a good xeno-free alternative to FBS for NK expansion. Overall, we demonstrated a feeder-cell-free and FBS-free protocol that leverages NK Cloudz as a promising step toward a commercial GMP manufacturing method to expand NK cells for therapeutic use.

Using two-dimensional ultrasound imaging to examine venous pressure.

Ultrasound imaging is being used increasingly to aid in the teaching of human physiology and anatomy. Here we describe how its use can be integrated into the teaching of concepts surrounding venous circulation, specifically 1) venous valves and the muscle pump, 2) the effects of hydrostatic pressure on venous pressure, and 3) central venous pressure. The imaging procedures described are relatively simple but add a dimension that helps deliver the teaching points clearly and is enjoyable for students. They also aid in the link of basic physiology to clinical aspects of venous circulatory physiology.

Understanding basic vein physiology and venous blood pressure through simple physical assessments.

An understanding of the complexity of the cardiovascular system is incomplete without a knowledge of the venous system. It is important for students to understand that, in a closed system, like the circulatory system, changes to the venous side of the circulation have a knock-on effect on heart function and the arterial system and vice versa. Veins are capacitance vessels feeding blood to the right side of the heart. Changes in venous compliance have large effects on the volume of blood entering the heart and hence cardiac output by the Frank-Starling Law. In healthy steady-state conditions, venous return has to equal cardiac output, i.e., the heart cannot pump more blood than is delivered to it. A sound understanding of the venous system is essential in understanding how changes in cardiac output occur with changes in right atrial pressure or central venous pressure, and the effect these changes have on arterial blood pressure regulation. The aim of this paper is to detail simple hands-on physiological assessments that can be easily undertaken in the practical laboratory setting and that illustrate some key functions of veins. Specifically, we illustrate that venous valves prevent the backflow of blood, that venous blood pressure increases from the heart to the feet, that the skeletal muscle pump facilitates venous return, and we investigate the physiological and clinical significance of central venous pressure and how it may be assessed.