Incorporating ultrasound training into undergraduate medical education in a faculty-limited setting.

BACKGROUND: Point of care ultrasound (POCUS) is becoming a major extension of patient care. From diagnostic efficacy to its widespread accessibility, POCUS has expanded beyond emergency departments to be a tool utilized by many specialties. With the expansion of its use, medical education has begun to implement ultrasound education earlier in curricula. However, at institutions without a formal ultrasound fellowship or curriculum, these students lack the fundamental knowledge of ultrasound. At our institution, we set out to incorporate an ultrasound curriculum, into undergraduate medical education utilizing a single faculty member and minimal curricular time. METHODS: Our stepwise implementation began with the development of a 3-hour fourth-year (M4) Emergency Medicine clerkship ultrasound teaching session, which included pre- and post-tests as well as a survey. The success with this session progressed to the development of a designated fourth-year ultrasound elective, which was evaluated with narrative feedback. Finally, we developed six 1-hour ultrasound sessions that correlated with first-year (M1) gross anatomy and physiology. A single faculty member was responsible for this curriculum and other instructors included residents, M4 students, and second-year (M2) near-peer tutors. These sessions also included pre- and post-tests and a survey. Due to curricular time limitations, all but the M4 Emergency Medicine clerkship session were optional. RESULTS: 87 students participated in the emergency medicine clerkship ultrasound session and 166 M1 students participated in the voluntary anatomy and physiology ultrasound sessions. All participants agreed or strongly agreed that they would like more ultrasound training, that ultrasound training should be integrated into all four years of undergraduate medical education. Students were in strong agreement that the ultrasound sessions helped increase understanding of anatomy and anatomical identification with ultrasound. CONCLUSION: We describe the stepwise addition of ultrasound into the undergraduate medical education curriculum of an institution with limited faculty and curricular time.

Prolonging the Shelf Life of Homemade Gelatin Ultrasound Phantoms.

A significant limitation of homemade phantoms is shelf life. Our goal was to compare the impact on shelf life of easily obtained additives. Fifteen additives were mixed into a gelatin-psyllium hydrophilic mucilloid fiber phantom; three of these additives were used as a layer on top of the phantom. The mixtures were stored in the refrigerator and at room temperature. The samples were evaluated daily for microbial growth and phantom degradation. A 4% of chlorhexidine gluconate layer on top of the phantom quickly made the phantom unusable. The addition of benzoic acid and bleach to the mixture negatively affected phantom appearance with ultrasound imaging. The addition of household bleach or 4% chlorhexidine gluconate to the mixture or a 10% povidone-iodine layer on top of the phantom was the best way to preserve samples stored at room temperature. The refrigerated sample outlasted the paired room temperature sample in every case, with most room temperature samples becoming unusable by day 10 and most refrigerated samples lasting past 50 days.

A Realistic and Inexpensive Ultrasound Phantom for Teaching M-Mode Measurement of Fetal Heart Rate.

BACKGROUND: M-mode ultrasound is frequently used to measure a fetal heart rate. Phantoms are used to simulate clinical conditions for teaching ultrasound-related skills. This is particularly important in the case of early pregnancy, when it is not ethical to use a live fetus in utero for teaching purposes. OBJECTIVES: To date, no phantom has been created to model the beating heart of an intrauterine pregnancy. Our goal was to create such a model for use in teaching M-mode ultrasound. MATERIALS AND METHODS: The phantom is constructed using a toy fish, several balloons, and water-absorbing gel crystals. RESULTS: We have created a novel phantom for use in teaching M-mode measurements. The cost per phantom is around $20 and the phantom can be constructed in about 20 min. CONCLUSION: This phantom is easily constructed and cost-effective. It gives learners the opportunity to practice measuring an intrauterine fetal heart rate in a learning environment without exposing a live fetus to unnecessary ultrasound.

A Simple, Realistic, Inexpensive Nerve Phantom.

Ultrasound-guided nerve blocks are common techniques in several medical specialties. Phantoms are commonly used when teaching these procedures. Commercial phantoms are expensive, and most previously published "homemade" nerve phantoms have a substantial amount of posterior shadowing, making it difficult to visualize the needle posterior to the simulated nerve. We have constructed a simple and easy-to-make nerve block phantom using a hot dog core embedded in a gelatin-psyllium hydrophilic mucilloid fiber mixture that has little to no posterior shadowing.

Improving the Performance Time and Accuracy of Ultrasound-Guided Interventions: A Randomized Controlled Double-Blind Trial of the Line-of-Sight Approach and the "APPLES" Mnemonic.

OBJECTIVES: To determine whether the line-of-sight approach improved the performance time and accuracy of ultrasound (US)-guided needle placement targeting the subdeltoid bursa in a cadaver among novice operators compared to the side approach. A secondary objective was to determine whether participants thought the APPLES (angle, position, perpendicular, line up, entry, sweep) mnemonic was a helpful guide for performing the procedure. METHODS: Medical students and residents were randomized into either a line-of-sight or side approach group and then crossed over to the other group. The procedure time was determined by 2 blinded reviewers. A survey was administered to determine which method participants preferred and whether they thought the APPLES mnemonic was helpful. A paired t test was used to compare the performance time, and the McNemar test was used to compare the accuracy of the methods. RESULTS: Among the 110 participants, the performance time with the line-of-sight approach (mean, 14.4 seconds; SD, 9.95 seconds) was significantly decreased compared to the side approach (mean, 18.6 seconds; SD, 10.1 seconds; P = .00029). Additionally, participants who only hit the target using one method were more likely to hit the target in 30 seconds using the line-of-sight approach (P = .035). In total, 72.7% of participants preferred the line-of-sight approach over the side approach, and 88.2% of participants thought that APPLES mnemonic was useful. CONCLUSIONS: This study highlights the finding that positioning of the operator is important in performing US-guided interventions, and the line-of-sight approach may improve the performance time and accuracy among novice operators. Furthermore, the APPLES mnemonic serves as a useful educational tool for teaching US-guided interventional procedures.

Reduced Survival Outcome After Receiving a New Cancer Diagnosis in the Emergency Department: Findings from a Hospital Network in Rural Eastern North Carolina.

PURPOSE: Patients whose cancer was found during an Emergency Department (ED) visit often present at later stages when survival outcomes are worse. Limited research has characterized the survival experience of cancer patients who receive their diagnosis through the ED versus those who do not. METHODS: A retrospective cohort study identified all patients presenting to the ED between 2014 and 2015 in a rural, regional hospital system with a visit or resulting admission associated with an oncologic ICD-9 code. The chart was abstracted to determine a new cancer diagnosis versus an existing case. Cox proportional hazards (HR) estimated survival time. Patient and cancer characteristics were compared between those who were newly diagnosed through the ED and patients who were not. FINDINGS: Thirty-nine percent of patients in our sample received their new cancer diagnosis as a result of an ED visit. The median survival was lower in cancer cases diagnosed through the ED (13 vs. 39 months, P < .001), men (20 vs. 32 months, P < .001), and patients aged ≥ 65 (22 months vs. 32 months, P < .001). Factors associated with lower survival were having a type of cancer location other than breast (HR = 1.96; P < .001), followed by being newly diagnosed with cancer through the ED (HR = 1.71; P < .001), and stage IV at diagnosis (HR = 1.70; P < .001). CONCLUSIONS: Patients who received a new cancer diagnosis through the ED and required subsequent hospitalization had shorter overall survival and presented with advanced disease. Future research should address socioeconomic factors that may influence these patterns of cancer presentation.

Realistic and inexpensive ultrasound phantoms to demonstrate aortic aneurysm and aortic dissection.

Introduction: Using ultrasound to evaluate for the presence of aortic pathology is a common procedure in the emergency department. Phantoms are models that are used to simulate clinical conditions for teaching ultrasound-related skills. To date, no 'homemade' phantom has been created to model aortic aneurysms, and no phantoms exist to model aortic dissection. Methods: We used several readily available, inexpensive ingredients to create ultrasound phantoms. Results: These phantoms realistically mimic aortic aneurysm and aortic dissection. Discussion: These are the first 'homemade' phantoms that demonstrate aortic pathology. Conclusions: We have created realistic, affordable, easily reproducible phantoms for use in teaching clinicians to use ultrasound when evaluating patients for aortic aneurysm and/or aortic dissection.

Impact of Predefined Angles and a Revised APPLES Mnemonic on Accuracy and Performance Time for Simulated Ultrasound-Guided Injections.

OBJECTIVES: Our objective was to determine whether predefined angles would improve performance time and accuracy of ultrasound-guided procedures by novice operators and whether a revised APPLES (approach, position, perpendicular, lift, entry, sweep) mnemonic was a helpful guide for performing the procedure. METHODS: Participants attempted to hit targets in-plane and out-of-plane at different depths with a needle under ultrasound guidance with and without predefined angles. Participants were then asked if they thought that the mnemonic would be helpful when learning both methods for ultrasound-guided procedures. RESULTS: There were 120 participants all of whom had performed fewer than six ultrasound guided procedures. Accuracy increased in all groups when angles were provided; however, only the 3-cm in-plane approach achieved statistical significance. Performance time also achieved statistical significance in two of the four groups. Ninety-five percent of participants thought that the revised APPLES mnemonic would be helpful for learning and performing ultrasound-guided procedures in the future. CONCLUSIONS: Predefined angles seem to positively impact procedure time and accuracy for some target depths, and the APPLES mnemonic could be a helpful mental checklist for many novice operators. These may be useful tools to facilitate safe and efficient ultrasound-guided procedures in the clinical space.

A temperature-regulated Campylobacter jejuni gluconate dehydrogenase is involved in respiration-dependent energy conservation and chicken colonization.

Campylobacter jejuni is a gastrointestinal pathogen of humans but can asymptomatically colonize the avian gut. C. jejuni therefore grows at both 37 degrees C and 42 degrees C, the internal temperatures of humans and birds respectively. Microarray and proteomic studies on temperature regulation in C. jejuni strain 81-176 revealed the upregulation at 42 degrees C of two proteins, Cj0414 and Cj0415, orthologous to gluconate dehydrogenase (GADH) from Pectobacterium cypripedii. 81-176 demonstrated GADH activity, converting d-gluconate to 2-keto-d-gluconate, that was higher at 42 degrees C than at 37 degrees C. In contrast, cj0414 and cj0415 mutants lacked GADH activity. Wild-type but not cj0415 mutant bacteria exhibited gluconate-dependent respiration. Neither strain grew in defined media with d-gluconate or 2-keto-d-gluconate as a sole carbon source, revealing that gluconate was used as an electron donor rather than as a carbon source. When administered to chicks individually or in competition with wild-type, the cj0415 mutant was impaired in establishing colonization. In contrast, there were few significant differences in colonization of BALB/c-ByJ mice in single or mixed infections. These results suggest that the ability of C. jejuni to use gluconate as an electron donor via GADH activity is an important metabolic characteristic that is required for full colonization of avian but not mammalian hosts.

Cj0596 is a periplasmic peptidyl prolyl cis-trans isomerase involved in Campylobacter jejuni motility, invasion, and colonization.

BACKGROUND: Campylobacter jejuni is a gastrointestinal pathogen of humans, but part of the normal flora of poultry, and therefore grows well at the respective body temperatures of 37 degrees C and 42 degrees C. Proteomic studies on temperature regulation in C. jejuni strain 81-176 revealed the upregulation at 37 degrees C of Cj0596, a predicted periplasmic chaperone that is similar to proteins involved in outer membrane protein folding and virulence in other bacteria. RESULTS: The cj0596 gene was highly conserved in 24 strains and species of Campylobacter, implying the importance of this gene. To study the role that Cj0596 plays in C. jejuni pathogenesis, a mutant derivative of strain 81-176 was constructed in which the cj0596 gene was precisely deleted. A revertant of this mutant was isolated by restoring the gene to its original chromosomal location using streptomycin counterselection. The cj0596 mutant strain demonstrated a slightly decreased growth rate and lower final growth yield, yet was more motile and more invasive of human intestinal epithelial cells than wild-type. In either single or mixed infections, the mutant was less able to colonize mice than 81-176. The cj0596 mutant also expressed altered levels of several proteins. CONCLUSION: Mutation of cj0596 has an effect on phenotypes related to C. jejuni pathogenesis, probably due to its role in the proper folding of critical outer membrane proteins.

Angioedema after thrombolysis with tissue plasminogen activator: an airway emergency.

Recombinant tissue plasminogen activator (rtPA), an enzyme that catalyzes the conversion of plasminogen to plasmin resulting in fibrinolysis, is used for the treatment of acute ischemic strokes. The use of this medication is not without complication. One complication of this therapy is angioedema. This complication can be life-threatening if not recognized quickly. However, the potential for the development of angioedema after rtPA administration is not widely known. This is a case of a 60-year-old man who suffered an acute ischemic stroke and was given rtPA. The patient subsequently developed rapidly progressing angioedema leading to airway compromise. The patient was intubated with some difficulty and the angioedema improved and the patient was able to be extubated the next day. Angioedema secondary to administration of rtPA is thought to be bradykinin mediated, but the exact mechanism is unknown. Treatment with FFP, Icatibant, Ecallantide or a C1-esterase inhibitor can be considered.

Mutation of PEB4 alters the outer membrane protein profile of Campylobacter jejuni.

Campylobacter jejuni is a significant cause of human gastroenteritis worldwide. In an attempt to further define bacterial factors that influence infectivity, Cj0596 was identified as playing a role in C. jejuni virulence. Cj0596 is a periplasmic chaperone that is similar to proteins involved in outer membrane protein (OMP) folding in other bacteria. Mutation of cj0596 caused an alteration in the levels of eight OMPs, compared with wild-type bacteria. Replacement of the cj0596 mutation with the wild-type cj0596 gene restored a wild-type OMP profile. The altered OMP profile in the cj0596 mutant was accompanied by significant changes in several virulence properties, including an increase in the ability to autoagglutinate, increased susceptibility to several antimicrobial agents, and increased biofilm formation. In summary, mutation of cj0596 alters the C. jejuni OMP profile and leads to changes in OMP-related phenotypes involved in C. jejuni pathogenesis.