Determination of Endovaginal Ultrasound Proficiency and Learning Curve Among Emergency Medicine Trainees.

OBJECTIVES: Performing and interpreting endovaginal ultrasound is an important skill used during the evaluation of obstetric and gynecologic emergencies. This study aims to describe the level of proficiency and confidence achieved after performing 25 endovaginal examinations. METHODS: This is a prospective study at a single urban academic emergency department. Participants performed a minimum of 25 endovaginal ultrasounds under the supervision of a point-of-care ultrasound expert. Anatomical structures were identified by the expert under ultrasound prior to each session. Each examination was scored for agreement of findings between the participant and expert. The data were used to develop a performance curve identifying when proficiency was achieved, where experiential benefit diminished, and when participants felt confident. RESULTS: A total of 1117 endovaginal ultrasound examinations were performed by 50 participants. Agreement after 25 examinations was highest (>95%) for probe insertion and preparation, bladder and uterus identification, and directionality. Agreement was lowest for identification of the ovaries (76%). Experiential benefit plateaus occurred earliest (10 exams) for preparation and insertion followed by bladder identification and directionality. Surprisingly, ovarian experiential benefit plateaued at 16 exams. Participant confidence improved overall and was lowest for the identification of ovaries and abnormal pelvic anatomy. CONCLUSIONS: There is a significant learning curve when performing endovaginal ultrasound. Our data do not support the use of 25 examinations as a minimum standard for identification of the ovaries or abnormal ovarian pathology.

A New Inexpensive Simulation Model for Ultrasound Assessment of Optic Nerve Sheath Diameter.

BACKGROUND: Sonographic measurement of optic nerve sheath diameter (ONSD) is becoming increasingly accepted as a diagnostic modality to detect elevations in intracranial pressure. As this technique becomes more widespread, methods to address the inherent operator-dependent nature of this modality will need to be developed. We propose a novel low-cost model to accurately simulate sonographic ONSD measurement for purposes of training and assessment. METHODS: We designed models composed of medical tubing of various diameters readily available from typical hospital supplies and suspended them in gelatin. The models were evaluated by ultrasound by three expert point-of-care sonographers using a standard linear array probe and technique proposed in the literature. RESULTS: This model generates faithful simulation of the ONS that closely approximates in vivo images and can be used to produce accurate, reproducible measurements. Materials are low cost and easy to acquire and assemble. CONCLUSIONS: Our model provides realistic simulated images of the ONS. Through comparison of sonographic measurements to the known tube diameters, this model serves as a promising inexpensive tool to teach the method of ultrasound assessment of ONSD or as a way to determine accuracy of this novel ultrasound technology.

The Canadian Medical Student Ultrasound Curriculum: A Statement From the Canadian Ultrasound Consensus for Undergraduate Medical Education Group.

OBJECTIVES: This study sought to establish by expert review a consensus-based, focused ultrasound curriculum, consisting of a foundational set of focused ultrasound skills that all Canadian medical students would be expected to attain at the end of the medical school program. METHODS: An expert panel of 21 point-of-care ultrasound and educational leaders representing 15 of 17 (88%) Canadian medical schools was formed and participated in a modified Delphi consensus method. Experts anonymously rated 195 curricular elements on their appropriateness to include in a medical school curriculum using a 5-point Likert scale. The group defined consensus as 70% or more experts agreeing to include or exclude an element. We determined a priori that no more than 3 rounds of voting would be performed. RESULTS: Of the 195 curricular elements considered in the first round of voting, the group reached consensus to include 78 and exclude 24. In the second round, consensus was reached to include 4 and exclude 63 elements. In our final round, with 1 additional item added to the survey, the group reached consensus to include an additional 3 and exclude 8 elements. A total of 85 curricular elements reached consensus to be included, with 95 to be excluded. Sixteen elements did not reach consensus to be included or excluded. CONCLUSIONS: By expert opinion-based consensus, the Canadian Ultrasound Consensus for Undergraduate Medical Education Group recommends that 85 curricular elements be considered for inclusion for teaching in the Canadian medical school focused ultrasound curricula.

Orthopaedic residents demonstrate retention of point of care ultrasound knowledge after a brief educational session: a quasi experimental study.

BACKGROUND: Musculoskeletal point of care ultrasound (MSK POCUS) has many uses for orthopaedic surgeons, but orthopaedic trainees are rarely exposed to this modality. The purpose of this project was to assess the usefulness in clinical education of a newly implemented MSK POCUS course in an orthopaedic surgery program. METHODS: An MSK POCUS course for orthopaedic surgery residents was developed by an interdisciplinary team. Online videos were created to be viewed by residents prior to a half-day long practical course. An online survey covering the level of training of the resident and their previous use of ultrasound (total hours) was completed by the participants prior to the course. Resident's knowledge acquisition was measured with written pre-course, same-day post-course and six-month follow-up tests. Residents were also scored on a practical shoulder examination immediately after the course and at six-month follow-up. Changes in test scores between time points were evaluated using Wilcoxon signed-rank tests. RESULTS: Ten orthopaedic surgery residents underwent the MSK POCUS curriculum. Pre-course interest in MSK-POCUS was moderate (65%) and prior exposure was low (1.5 h mean total experience). Written test scores improved significantly from 50.7 ± 17.0% before to 84.0 ± 10.7% immediately after the course (p < 0.001) and suffered no significant drop at 6 months (score 75.0 ± 8.7%; p = 0.303). Average post-course practical exam score was 78.8 ± 3.1% and decreased to 66.2 ± 11.3% at 6 months (p = 0.012). Residents significantly improved their subjective comfort level with all aspects of ultrasound use at 6 months (p = 0.007-0.018) but did not significantly increase clinical usage frequency. CONCLUSION: An MSK POCUS curriculum was successfully developed and implemented using an interdisciplinary approach. The course succeeded in improving the residents' knowledge, skills, and comfort with MSK POCUS. This improvement was maintained at 6 months on the written test but did not result in higher frequency of use by the residents.

Bedside Identification of Massive Pulmonary Embolism with Point-of-Care Transesophageal Echocardiography.

BACKGROUND: Pulmonary embolism can be difficult to diagnose, particularly in those who are hemodynamically unstable and cannot be imaged to confirm the diagnosis. Echocardiography can allow for rapid assessment of patients in shock, but requires adequate transthoracic windows to obtain clinically useful information. Emergency physician-performed transesophageal echocardiography (TEE) may be a useful tool when transthoracic echocardiography fails. CASE REPORT: An 86-year-old woman presented to the emergency department after a fall at home. She rapidly decompensated in the emergency department and sustained a pulseless electrical activity cardiac arrest. Attempts made during the resuscitation to obtain transthoracic echocardiographic views to elicit the cause of the patient's cardiac arrest were unsuccessful. An emergency physician, with previous focused training in TEE, performed emergent TEE. The TEE examination rapidly revealed a dilated right ventricle and an empty, hyperdynamic left ventricle, suggestive of an unsuspected massive acute pulmonary embolism. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: With continued growth and utility of point-of-care ultrasound in emergency medicine, TEE provides an attractive means to assess critically ill patients that may not otherwise be assessable.

Comparison of lung ultrasound scoring systems for the prognosis of COVID-19 in the emergency department: An international prospective cohort study.

Purpose: The purpose of this study was to evaluate whether the lung ultrasound (LUS) scores applied to an international cohort of patients presenting to the emergency department (ED) with suspected COVID-19, and subsequently admitted with proven disease, could prognosticate clinical outcomes. Methods: This was an international, multicentre, prospective, observational cohort study of patients who received LUS and were followed for the composite primary outcome of intubation, intensive care unit (ICU) admission or death. LUS scores were later applied including two 12-zone protocols ('de Alencar score' and 'CLUE score'), a 12-zone protocol with lung and pleural findings ('Ji score') and an 11-zone protocol ('Tung-Chen score'). The primary analysis comprised logistic regression modelling of the composite primary outcome, with the LUS scores analysed individually as predictor variables. Results: Between April 2020 to April 2022, 129 patients with COVID-19 had LUS performed according to the protocol and 24 (18.6%) met the composite primary endpoint. No association was seen between the LUS score and the composite primary end point for the de Alencar score [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97-1.11; P = 0.29], the CLUE score (OR = 1.03; 95% CI: 0.96-1.10; P = 0.40), the Ji score (OR = 1.02; 95% CI: 0.97-1.07; P = 0.40) or the Tung-Chen score (OR = 1.02; 95% CI: 0.97-1.08). Discussion: Compared to these earlier studies performed at the start of the pandemic, the negative outcome of our study could reflect the changing scenario of the COVID-19 pandemic, including patient, disease, and system factors. The analysis suggests that the study may have been underpowered to detect a weaker association between a LUS score and the primary outcome. Conclusion: In an international cohort of adult patients presenting to the ED with suspected COVID-19 disease who had LUS performed and were subsequently admitted to hospital, LUS severity scores did not prognosticate the need for invasive ventilation, ICU admission or death.

Just the facts: brachial plexus blocks for upper extremity injuries in the emergency department.

Ultrasound-guided nerve blocks (UGNBs) are becoming a more common method for pain control in the emergency department. Specifically, brachial plexus blocks have shown promise for acute upper extremity injuries as well as an alternative to procedural sedation for glenohumeral reductions. Unfortunately, there is minimal discussion in the EM literature regarding phrenic nerve paralysis (a well-known complication from brachial plexus blocks). The anatomy of the brachial plexus, its relationship to the phrenic nerve, and why ultrasound-guided brachial plexus blocks can cause phrenic nerve paralysis and resultant respiratory impairment will be discussed. The focus on patient safety is paramount, and those with preexisting respiratory conditions, extremes of age or weight, spinal deformities, previous neck injuries, and anatomical variations are at greater risk. We put forth different block strategies for risk mitigation, including patient selection, volume and type of anesthetic, block location, postprocedural monitoring, and specific discharge instructions. Understanding the benefits and risks of UGNBs is critical for emergency physicians to provide effective pain control while ensuring optimal patient safety.

POCUS literature primer: key papers on POCUS in cardiac arrest and shock.

OBJECTIVE: The objective of this study is to identify the top five most influential papers published on the use of point-of-care ultrasound (POCUS) in cardiac arrest and the top five most influential papers on the use of POCUS in shock in adult patients. METHODS: An expert panel of 14 members was recruited from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative. The members of the panel are ultrasound fellowship trained or equivalent, are engaged in POCUS research, and are leaders in POCUS locally and nationally in Canada. A modified Delphi process was used, consisting of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers for the use of POCUS in cardiac arrest and shock. RESULTS: The panel identified 39 relevant papers on POCUS in cardiac arrest and 42 relevant papers on POCUS in shock. All panel members participated in all three rounds of the modified Delphi process, and we ultimately identified the top five most influential papers on POCUS in cardiac arrest and also on POCUS in shock. Studies include descriptions and analysis of safe POCUS protocols that add value from a diagnostic and prognostic perspective in both populations during resuscitation. CONCLUSION: We have developed a reading list of the top five influential papers on the use of POCUS in cardiac arrest and shock to better inform residents, fellows, clinicians, and researchers on integrating and studying POCUS in a more evidence-based manner.

RéSUMé: OBJECTIF: L'objectif de cette étude est d'identifier les cinq articles les plus influents publiés sur l'utilisation de l'échographie au point de soin (POCUS) dans l'arrêt cardiaque et les cinq articles les plus influents sur l'utilisation de POCUS dans le choc chez les patients adultes. MéTHODES: Un comité d'experts composé de 14 membres a été recruté par le Comité d'échographie d'urgence de l'Association canadienne des médecins d'urgence (ACMU) et le Canadian Ultrasound Fellowship Collaborative. Les membres du comité sont formés en échographie ou l'équivalent, participent à la recherche sur le POCUS et sont des chefs de file du POCUS à l'échelle locale et nationale au Canada. Un processus Delphi modifié a été utilisé, consistant en trois séries de sondages séquentiels et de discussions pour parvenir à un consensus sur les cinq articles les plus influents pour l'utilisation de POCUS dans les arrêts cardiaques et les chocs. RéSULTATS: Le panel a identifié 39 articles pertinents sur le POCUS en arrêt cardiaque et 42 articles pertinents sur le POCUS en état de choc. Tous les membres du panel ont participé aux trois cycles du processus Delphi modifié, et nous avons finalement identifié les cinq articles les plus influents sur le POCUS en arrêt cardiaque et aussi sur le POCUS en état de choc. Les études comprennent des descriptions et des analyses de protocoles POCUS sûrs qui ajoutent de la valeur d'un point de vue diagnostique et pronostique dans les deux populations pendant la réanimation. CONCLUSION: Nous avons dressé une liste de lecture des cinq principaux articles influents sur l'utilisation du POCUS en cas d'arrêt cardiaque et de choc afin de mieux informer les résidents, les boursiers, les cliniciens et les chercheurs sur l'intégration et l'étude du POCUS d'une manière plus factuelle.

Carotid Flow Time Compared with Invasive Monitoring as a Predictor of Volume Responsiveness in ICU patients.

Objectives: Identifying patients who will have an increase in their cardiac output from volume administration is difficult to identify. We propose the use of carotid flow time, which is a non-invasive means to determine if a patient is volume responsive. Methods: Patients admitted to a critical care unit with a pulmonary artery catheter in place were enrolled. We perform a carotid flow time and pulmonary artery catheter measurement of cardiac output pre and post-passive leg raise and comparing the two. An increase of 10% change in the pre- vs. post-passive leg raise measurement would be indicative of a patient who is volume responsive. Results: We identified 8 patients who were volume responsive as determined by the gold standard pulmonary artery catheter. The sensitivity 87.5% and specificity 90.9%. Pearson correlation coefficient between PA-CO measurements and CFT was r=0.8316, indicative of strong correlation between the two measurements. Conclusion: In our patient sample of critically ill patients with pulmonary artery catheters, we found a strong correlation between corrected carotid flow times and cardiac output measurements from pulmonary artery catheters.

Optimizing simulator-based training for emergency transesophageal echocardiography: A randomized controlled trial.

Background: Resuscitative clinician-performed transesophageal echocardiography (TEE) is a relatively novel ultrasound application; however, optimal teaching methods have not been determined. Previous studies have demonstrated that variable practice (VP), where practice conditions are changed, may improve learning of procedural skills compared with blocked practice (BP), where practice conditions are kept constant. We compared VP and BP for teaching resuscitative TEE to emergency medicine residents using a simulator. Methods: Emergency medicine residents with no prior TEE experience were randomized to the BP or VP groups. The BP group practiced 10 repetitions of a fixed five-view TEE sequence, while the VP group practiced 10 different random five-view TEE sequences on a simulator. Participants completed a performance assessment immediately after training and a transfer test 2 weeks after training. Ultrasound images and transducer motion metrics were captured by the simulator for blinded analysis. The primary outcome was the percentage of successful views on the transfer test. Results: Twenty-eight participants completed the study (14 in the BP group, 14 in the VP group). The BP group had a higher rate of successful views compared with the VP group on the transfer test (93.6% vs. 77.6%; p = 0.002). The BP group also had higher image quality on a 5-point scale (3.3 vs. 2.9; p = 0.01) and fewer probe angular changes (2982.5 degrees vs. 4239.8 degrees; p = 0.04). There were no statistically significant differences between the groups for the rate of correct diagnoses, confidence level, or scan time. Conclusions: Practicing a fixed sequence of views was more effective than a variable sequence of views for learning resuscitative TEE on a simulator. These results should be validated in TEE scans performed in the clinical environment.

Flow Cytometric Enumeration of Peripheral Blood CD34+ Cells Predicts Bone Marrow Pathology in Patients with Less Than 1% Blasts by Manual Count.

Background and Aims: Significance of absolute number of CD34+ cells in the peripheral blood of patients with less than 1% myeloblasts by manual differential count is unknown and our aim is to study its relevance in clinical practice. Methods: We studied 138 peripheral bloods flow cytometric analyses in patients with less than 1% myeloblasts by manual differential, when CD34+ events were present in the gate that encompassed lymphocytes, monocytes, stem cells, and blasts. Results: The average absolute number of CD34+cells in the peripheral blood was 11 CD34+cells/µL ranging from less than 1 cell/µL to 147 cells/µL. The average absolute number of CD34+ cells in patients with an abnormal expansive process involving bone marrow (metastases, myelodysplasia, granulomas, marrow infections) or if bone marrow biopsy not performed, presumed expansive marrow process was 25 cells/µL, and in patients without an expansive marrow process (or presumed negative) was 4 cells/µL (P<0.00007). Cutoff 12 CD34+ cells/µL had 93% positive predictive value for bone marrow involvement by an expansive process and 78% negative predictive value. Conclusion: Flow cytometric testing of the peripheral blood is extremely sensitive method for enumerating CD34+ cells and can detect fewer than one CD34+ cell/µL. The absolute number of CD34+ cells in the peripheral blood is a useful parameter in determining marrow involvement by an expansive process and may provide guidance with respect to the necessity for bone marrow biopsy.

Point-of-Care Ultrasound (POCUS) Literature Primer: Key Papers on Renal and Biliary POCUS.

Objective The objective of this study is to identify the top five influential papers published on renal point-of-care ultrasound (POCUS) and the top five influential papers on biliary POCUS in adult patients. Methods A 14-member expert panel was recruited from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative. All panel members have had ultrasound fellowship training or equivalent, are actively engaged in POCUS scholarship, and are involved with POCUS at their local site and nationally in Canada. We used a modified Delphi process consisting of three rounds of sequential surveys and discussion to achieve consensus on the top five influential papers for renal POCUS and biliary POCUS. Results The panel identified 27 relevant papers on renal POCUS and 30 relevant papers on biliary POCUS. All panel members participated in all three rounds of the modified Delphi process, and after completing this process, we identified the five most influential papers on renal POCUS and the five most influential papers on biliary POCUS. Conclusion We have developed a list, based on expert opinion, of the top five influential papers on renal and biliary POCUS to better inform all trainees and clinicians on how to use these applications in a more evidence-based manner. This list will also be of interest to clinicians and researchers who strive to further advance the field of POCUS.

Intubation practices and outcomes for patients with suspected or confirmed COVID-19: a national observational study by the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN).

OBJECTIVE: Intubation practices changed during the COVID-19 pandemic to protect healthcare workers from transmission of disease. Our objectives were to describe intubation characteristics and outcomes for patients tested for SARS CoV-2 infection. We compared outcomes between patients testing SARS COV-2 positive with those testing negative. METHODS: We conducted a health records review using the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) registry. We included consecutive eligible patients who presented to one of 47 EDs across Canada between March 1, 2020 and June 20, 2021, were tested for SARS-CoV-2 and intubated in the ED. The primary outcome was the proportion of patients experiencing a post-intubation adverse event during the ED stay. Secondary outcomes included first-pass success, intubation practices, and hospital mortality. We used descriptive statistics to summarize variables with subgroup differences examined using t tests, z tests, or chi-squared tests where appropriate with 95% CIs. RESULTS: Of 1720 patients with suspected COVID-19 who were intubated in the ED during the study period, 337 (19.6%) tested SARS-CoV-2 positive and 1383 (80.4%) SARS-CoV-2 negative. SARS-CoV-2 positive patients presented to hospital with lower oxygen levels than SARS-CoV-2 negative patients (mean pulse oximeter SaO2 86 vs 94%, p < 0.001). In total, 8.5% of patients experienced an adverse event post-intubation. More patients in the SARS-CoV-2 positive subgroup experienced post-intubation hypoxemia (4.5 vs 2.2%, p = 0.019). In-hospital mortality was greater for patients who experienced intubation-related adverse events (43.2 vs 33.2%, p = 0.018). There was no significant difference in adverse event-associated mortality by SARS-CoV-2 status. First-pass success was achieved in 92.4% of all intubations, with no difference by SARS-CoV-2 status. CONCLUSIONS: During the COVID-19 pandemic, we observed a low risk of adverse events associated with intubation, even though hypoxemia was common in patients with confirmed SARS-CoV-2. We observed high rates of first-pass success and low rates of inability to intubate. The limited number of adverse events precluded multivariate adjustments. Study findings should reassure emergency medicine practitioners that system modifications made to intubation processes in response to the COVID-19 pandemic do not appear to be associated with worse outcomes compared to pre-COVID-19 practices.

RéSUMé: OBJECTIF: Les pratiques d'intubation ont changé au cours de la pandémie de COVID-19 afin de protéger le personnel de santé contre la transmission de la maladie. Nos objectifs étaient de décrire les caractéristiques de l'intubation et les résultats pour les patients testés pour l'infection par le CoV-2 du SRAS. Nous avons comparé les résultats entre les patients testés positifs au SARS COV-2 et ceux testés négatifs. MéTHODES: Nous avons effectué un examen des dossiers de santé à l'aide du registre du Réseau canadien d'intervention rapide dans les services d'urgence pour la COVID-19 (RCIRSUC). Nous avons inclus les patients éligibles consécutifs qui se sont présentés à l'un des 47 services d'urgence du Canada entre le 1er mars 2020 et le 20 juin 2021, qui ont été testés pour le SRAS-CoV-2 et qui ont été intubés dans le service d'urgence. Le résultat principal était la proportion de patients ayant subi un événement indésirable après l'intubation pendant leur séjour aux urgences. Les critères de jugement secondaires comprenaient le succès du premier passage, les pratiques d'intubation et la mortalité hospitalière. Nous avons utilisé des statistiques descriptives pour résumer les variables avec des différences de sous-groupes examinées à l'aide de tests t, de tests z ou de tests du chi carré, le cas échéant, avec des IC à 95%. RéSULTATS: Sur les 1720 patients suspects de COVID-19 qui ont été intubés aux urgences pendant la période de l'étude, 337 (19,6%) ont été testés positifs au SARS-CoV-2 et 1383 (80,4%) négatifs au SARS-CoV-2. Les patients positifs au SRAS-CoV-2 se sont présentés à l'hôpital avec des niveaux d'oxygène inférieurs à ceux des patients négatifs pour le SRAS-CoV-2 (oxymètre de pouls moyen SaO2 86% contre 94%, p < 0,001). Au total, 8,5% des patients ont présenté un événement indésirable après l'intubation. Un plus grand nombre de patients du sous-groupe positif au SRAS-CoV-2 ont présenté une hypoxémie post-intubation (4,5% vs 2,2%, p = 0,019). La mortalité hospitalière était plus élevée chez les patients ayant subi des événements indésirables liés à l'intubation (43,2% vs 33,2%, p = 0,018). Il n'y avait pas de différence significative dans la mortalité associée aux événements indésirables selon le statut du SRAS-CoV-2. Le succès du premier passage a été obtenu dans 92,4% de toutes les intubations, sans différence selon le statut SARS-CoV-2 CONCLUSIONS: Pendant la pandémie de COVID-19, nous avons observé un faible risque d'événements indésirables associés à l'intubation, même si l'hypoxémie était fréquente chez les patients atteints de SRAS-CoV-2 confirmé. Nous avons observé des taux élevés de réussite du premier passage et des taux faibles d'incapacité à intuber. Le nombre limité d'événements indésirables a empêché les ajustements multivariés. Les résultats de l'étude devraient rassurer les praticiens de la médecine d'urgence que les modifications apportées aux processus d'intubation en réponse à la pandémie de COVID-19 ne semblent pas être associées à des résultats plus défavorables que les pratiques antérieures à la pandémie de COVID-19.

The erector spinae plane block for acute pain management in emergency department patients with rib fractures.

OBJECTIVE: Rib fractures represent a significant cause of morbidity and mortality in trauma patients. The erector spinae plane block has come to the forefront as a potential safe and effective option for analgesia in painful conditions of the thorax over multiple dermatomal levels. Given the high morbidity associated with rib fractures, the inadequacy of opioid analgesia and the strong safety profile of the erector spinae plane block, this pilot study sought to address whether this block can be used to safely and effectively provide analgesia in emergency department (ED) patients with acute rib fractures. METHODS: A total of nine patients underwent the procedure successfully. Patients were found to have a significant reduction in their pain score pre- and post-block. The reduction in mean pre- and post-block pain scores was 9.89 vs 3.56 which was statistically significant (p < 0.0001). CONCLUSION: In a pilot sampling of emergency department patients with acute fractures who failed traditional analgesic therapy, the erector spinae plane block performed by emergency physicians provided safe and effective pain control. Further research is needed to fully establish the clinical benefit and safety of this procedure.

RéSUMé: OBJECTIFS: Les fractures des côtes représentent une cause importante de morbidité et de mortalité chez les patients traumatisés. Le bloc du plan des muscles érecteurs du rachis est apparu comme une option potentiellement sûre et efficace pour l'analgésie dans les états douloureux du thorax sur plusieurs niveaux dermatomiques. Compte tenu de la morbidité élevée associée aux fractures des côtes, de l'insuffisance de l'analgésie opiacée et du profil d'innocuité solide d'un bloc du plan des muscles érecteurs du rachis, cette étude pilote visait à déterminer si ce bloc peut être utilisé pour fournir une analgésie sûre et efficace aux patients des urgences présentant des fractures aiguës des côtes. MéTHODES: Au total, neuf patients ont subi l'intervention avec succès. On a constaté que les patients avaient une réduction significative de leur score de douleur avant et après le blocage. La réduction des scores moyens de la douleur avant et après le blocage était de 9.89 contre 3.56, ce qui était statistiquement significatif (p < 0.0001). CONCLUSION: Dans le cadre d'un projet pilote d'échantillonnage de patients des services d'urgence ayant subi des fractures aiguës et ayant échoué à la thérapie analgésique traditionnelle, le bloc du plan des muscles érecteurs du rachis effectué par les médecins urgentistes a permis de contrôler efficacement et en toute sécurité la douleur. Des recherches supplémentaires sont nécessaires pour établir pleinement les avantages cliniques et la sécurité de cette procédure.

Liesegang rings in the setting of end-stage renal disease.

Introduction: Liesegang rings are acellular, lamellar, concentric rings of organic or inorganic material naturally formed in both biologic and environmental systems. Description in human tissue is scarce. Liesegang rings have exclusively been identified in association with pathologic disease processes and thus are not typically considered in differential diagnosis. They are usually described with cystic or inflammatory lesions. Histologically, Liesegang rings show features that are also seen in sections of parasitic ova, larvae, psammoma bodies, and by radiology as calcifications in cystic diseases of the breast and kidney. Case presentation: We noted at autopsy of a 59-year-old diabetic woman multiple black "stones" in the renal medulla. Microscopic examination demonstrated these to contain Liesegang rings. Conclusion: Liesegang rings formation should be considered in the differential diagnosis of atypical appearing deposits in the kidneys and other tissues. They may play a role in the pathogenesis of kidney stones.

Accuracy of Optic Nerve Sheath Diameter Measurements in Pocket-Sized Ultrasound Devices in a Simulation Model.

Introduction: Transorbital sonographic measurement of optic nerve sheath diameter (ONSD) is an emerging non-invasive technique for the identification and monitoring of intracranial hypertension. In recent years, new pocket ultrasound devices have become available, and it is uncertain if they have the resolution to measure such small structures appropriately as compared to their predecessors. In this study, we measure the performance of three ultrasound units on a simulation model to establish their precision and accuracy. Methods: ONSD was measured by three expert point-of-care sonographers using ultrasound machines three times on each of seven discrete ONS model sizes ranging from 3.5 to 7.9 mm. Two pocket ultrasounds (IVIZ, Sonosite, and Lumify, Philips) and one standard-sized portable ultrasound (M-Turbo, Sonosite) were used. Measurements were analyzed for mean error and variance and tested for significance using blocked covariance matrix regression analyses. Results: The devices differed in their variances (Lumify: 0.19 mm2, M-Turbo: 0.26 mm2, IVIZ: 0.34 mm2) and their mean error (Lumify: -0.05 mm, M-Turbo: 0.10 mm, IVIZ: -0.10 mm). The difference in mean error between users is not significant (p = 0.45), but there is a significant difference in mean error between devices (p = 0.02). Conclusions: Accurate ONSD measurement is possible utilizing pocket-sized ultrasound, and in some cases, may be more accurate than larger portable ultrasound units. While the differences in these devices were statistically significant, all three were highly accurate, with one pocket device (Lumify) outperforming the rest. Further study in human subjects should be conducted prior to using pocket ultrasound devices for in vivo diagnosis of intracranial hypertension.

Point of Care Ultrasound Literature Primer: Key Papers on Focused Assessment With Sonography in Trauma (FAST) and Extended FAST.

Objective The objective of this study is to identify the top five most influential papers published on focused assessment with sonography in trauma (FAST) and the top five most influential papers on the extended FAST (E-FAST) in adult patients. Methods An expert panel was recruited from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative. These experts are ultrasound fellowship-trained or equivalent, are involved with point-of-care ultrasound (POCUS) research and scholarship, and are leaders in both the POCUS program at their local site and within the national Canadian POCUS community. This 14-member expert group used a modified Delphi process consisting of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers for FAST and E-FAST. Results The expert panel identified 56 relevant papers on FAST and 40 relevant papers on E-FAST. After completing all three rounds of the modified Delphi process, the authors identified the top five most influential papers on FAST and the top five most influential papers on E-FAST. Conclusion We have developed a reading list of the top five influential papers for FAST and E-FAST that will benefit residents, fellows, and clinicians who are interested in using POCUS in an evidence-informed manner.

The CCEDRRN COVID-19 Mortality Score to predict death among nonpalliative patients with COVID-19 presenting to emergency departments: a derivation and validation study.

BACKGROUND: Predicting mortality from COVID-19 using information available when patients present to the emergency department can inform goals-of-care decisions and assist with ethical allocation of critical care resources. The study objective was to develop and validate a clinical score to predict emergency department and in-hospital mortality among consecutive nonpalliative patients with COVID-19; in this study, we define palliative patients as those who do not want resuscitative measures, such as intubation, intensive care unit care or cardiopulmonary resuscitation. METHODS: This derivation and validation study used observational cohort data recruited from 46 hospitals in 8 Canadian provinces participating in the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN). We included adult (age ≥ 18 yr) nonpalliative patients with confirmed COVID-19 who presented to the emergency department of a participating site between Mar. 1, 2020, and Jan. 31, 2021. We randomly assigned hospitals to derivation or validation, and prespecified clinical variables as candidate predictors. We used logistic regression to develop the score in a derivation cohort and examined its performance in predicting emergency department and in-hospital mortality in a validation cohort. RESULTS: Of 8761 eligible patients, 618 (7.0%) died. The CCEDRRN COVID-19 Mortality Score included age, sex, type of residence, arrival mode, chest pain, severe liver disease, respiratory rate and level of respiratory support. The area under the curve was 0.92 (95% confidence interval [CI] 0.90-0.93) in derivation and 0.92 (95% CI 0.90-0.93) in validation. The score had excellent calibration. These results suggest that scores of 6 or less would categorize patients as being at low risk for in-hospital death, with a negative predictive value of 99.9%. Patients in the low-risk group had an in-hospital mortality rate of 0.1%. Patients with a score of 15 or higher had an observed mortality rate of 81.0%. INTERPRETATION: The CCEDRRN COVID-19 Mortality Score is a simple score that can be used for level-of-care discussions with patients and in situations of critical care resource constraints to accurately predict death using variables available on emergency department arrival. The score was derived and validated mostly in unvaccinated patients, and before variants of concern were circulating widely and newer treatment regimens implemented in Canada. STUDY REGISTRATION: ClinicalTrials.gov, no. NCT04702945.