A shared point of care ultrasound curriculum for graduate medical education.

BACKGROUND: Point of care ultrasound (POCUS) education has grown significantly over the past two decades. Like most curricular items, POCUS education is siloed within individual graduate medical education (GME) programs. The purpose of this study was to evaluate the effectiveness of a shared GME POCUS curriculum between five GME programs at a single institution. METHODS: Post-graduate-year-1 (PGY-1) residents from emergency medicine (EM), family medicine (FM), internal medicine (IM), combined internal medicine-pediatrics (IM-Peds) and combined emergency medicine-pediatrics (EM-Peds) residency programs were enrolled in a core POCUS curriculum. The curriculum included eleven asynchronous online learning modules and ten hands-on training sessions proctored by sonographers and faculty physicians with POCUS expertise. Data was gathered about the curriculum's effectiveness including participation, pre- and post-curricular surveys, pre- and post-knowledge assessments, and an objective skills assessment. RESULTS: Of the 85 residents enrolled, 61 (72%) participated in the curriculum. Engagement varied between programs, with attendance at hands-on sessions varying the most (EM 100%, EM-Peds 100%, FM 40%, IM 22%, Med-Peds 11%). Pre- and post-knowledge assessment scores improved for all components of the curriculum. Participants felt significantly more confident with image acquisition, anatomy recognition, interpreting images and incorporating POCUS findings into clinical practice (p < 0.001) after completing the curriculum. CONCLUSION: In this shared GME POCUS curriculum, we found significant improvement in POCUS knowledge, attitudes, and psychomotor skills. This shared approach may be a viable way for other institutions to provide POCUS education broadly to their GME programs.

Rapid photothermal assay for ultrasensitive point-of-care detection of tumor markers based on a filter membrane.

An ultrasensitive photothermal assay was designed for point-of-care testing (POCT) of tumor markers based on a filter membrane. Firstly, Cu2-xSe was successfully encapsulated in liposome spheres with biotin on the surface and connected to carcinoembryonic antigen (CEA) aptamer with 3'end modified biotin by streptavidin. Secondly, the CEA antibody was successfully modified on the surface of the nitrocellulose membrane through simple incubation. Finally, the assay process was completed using a disposable syringe, and the temperature was recorded using a handheld infrared temperature detector. In the range 0-50 ng mL-1, the temperature change of the nitrocellulose membrane has a strong linear relationship with CEA concentration, and the detection limit is 0.097 ng mL-1. It is worth noting that the entire testing process can be easily performed in 10 min, much shorter than traditional clinical methods. In addition, this method was successfully applied to the quantitative determination of CEA levels in human serum samples with a recovery of 96.2-103.3%. This rapid assay can be performed by "one suction and one push" through a disposable syringe, which is simple to operate, and the excellent sensitivity reveals the great potential of the proposed strategy in the POCT of tumor biomarkers.

Utility of Point-of-Care Diagnosis of Chronic Heart Failure Using an Express Test for Semi-Quantitative Determination of NT-proBNP Levels.

AIM: To evaluate the accuracy of a rapid test for semi-quantitative determination of NT-proBNP levels in the diagnosis of CHF in comparison with quantitative assessment; to study the strength of the association of the results of this NT-proBNP test with indicators of the CHF severity. MATERIAL AND METHODS: The concentration of NT-proBNP was determined in 44 patients at bedside both semi-quantitatively using an express test (BioTest, Novosibirsk) and quantitatively in a laboratory. In 11 patients, the severity of CHF was assessed with the CHF Clinical Status Scale (CSS). Echocardiography was performed in all patients. RESULTS: The sensitivity of the quantitative and semi-quantitative tests coincided and was 95%. The specificity of the quantitative test was 100% in our study, whereas the semi-quantitative test showed a specificity of 92%. The negative predictive value of either test was 96%. The diagnostic accuracy was 98% and 93%, respectively. In patients with significantly high NT-proBNP concentrations, the semi-quantitative test demonstrated a reduced ability to verify values above 1800 pg/ml; in patients with threshold concentrations, the semi-quantitative test showed an increased subthreshold sensitivity. Increases in the NT-proBNP concentration correlated with the severity of CHF according to the stage of the disease. CONCLUSION: Due to the sufficiently high sensitivity, specificity, ease of use, and speed of obtaining results, the rapid test for semi-quantitative measuring NT-proBNP is promising for outpatient screening bedside diagnosis of CHF and in the emergency room to confirm or exclude CHF. When determining the dynamics of NT-proBNP during the treatment of CHF, the use of the semi-quantitative rapid test with visual assessment of the results may produce an error compared to the quantitative assessment, which will probably not allow tracking the effect of therapy or predicting exacerbation of the disease.

Paper-Based Microfluidic Analytical Device Patterned by Label Printer for Point-of-Care Blood Glucose and Hematocrit Detection Using 3D-Printed Smartphone Cassette.

This study presents a portable, low-cost, point-of-care (POC) system for the simultaneous detection of blood glucose and hematocrit. The system consists of a disposable origami microfluidic paper-based analytical device (µPAD) for plasma separation, filtration, and reaction functions and a 3D-printed cassette for hematocrit and blood glucose detection using a smartphone. The origami µPAD is patterned using a cost-effective label printing technique instead of the conventional wax printing method. The 3D-printed cassette incorporates an array of LED lights, which mitigates the effects of intensity variations in the ambient light and hence improves the accuracy of the blood glucose and hematocrit concentration measurements. The hematocrit concentration is determined quantitatively by measuring the distance of plasma wicking along the upper layer of the origami µPAD, which is pretreated with sodium chloride and Tween 20 to induce dehydration and aggregation of the red blood cells. The filtered plasma also penetrates to the lower layer of the origami µPAD, where it reacts with embedded colorimetric assay reagents to produce a yellowish-brown complex. A color image of the reaction complex is captured using a smartphone inserted into the 3D-printed cassette. The image is analyzed using self-written RGB software to quantify the blood glucose concentration. The calibration results indicate that the proposed detection platform provides an accurate assessment of the blood glucose level over the range of 45-630 mg/dL (R2 = 0.9958). The practical feasibility of the proposed platform is demonstrated by measuring the blood glucose and hematocrit concentrations in 13 human whole blood samples. Taking the measurements obtained from commercial glucose and hematocrit meters as a benchmark, the proposed system has a differential of no more than 6.4% for blood glucose detection and 9.1% for hematocrit detection. Overall, the results confirm that the proposed µPAD is a promising solution for cost-effective and reliable POC health monitoring.

Automatic tablet-based monoplane quantification of stroke volume and left ventricular ejection fraction: A comparative assessment against computer-based biplane and monoplane tools.

BACKGROUND: Point-of-care cardiovascular left ventricle ejection fraction (LVEF) quantification is established, but automatic tablet-based stroke volume (SV) quantification with handheld ultrasound (HAND) devices is unexplored. We evaluated a tablet-based monoplane LVEF and LV volume quantification tool (AutoEF) against a computer-based tool (Tomtec) for LVEF and SV quantification. METHODS: Patients underwent HAND scans, and LVEF and SV were quantified using AutoEF and computer-based software that utilized either apical four-chamber views (Auto Strain-monoplane [AS-mono]) or both apical four-chamber and apical two-chamber views (Auto Strain-biplane [AS-bi]). Correlation and Bland-Altman analysis were used to compare AutoEF with AS-mono and AS-bi. RESULTS: Out of 43 participants, eight were excluded. AutoEF showed a correlation of .83 [.69:.91] with AS-mono for LVEF and .68 [.44:.82] for SV. The correlation with AS-bi was .79 [.62:.89] for LVEF and .66 [.42:.81] for SV. The bias between AutoEF and AS-mono was 4.88% [3.15:6.61] for LVEF and 17.46 mL [12.99:21.92] for SV. The limits of agreement (LOA) were [-5.50:15.26]% for LVEF and [-8.02:42.94] mL for SV. The bias between AutoEF and AS-bi was 6.63% [5.31:7.94] for LVEF and 20.62 mL [16.18:25.05] for SV, with LOA of [-1.20:14.47]% for LVEF and [-4.71:45.94] mL for SV. CONCLUSION: LVEF quantification with AutoEF software was accurate and reliable, but SV quantification showed limitations, indicating non-interchangeability with neither AS-mono nor AS-bi. Further refinement of AutoEF is needed for reliable SV quantification at the point of care.

Identifying Frailty Using Point-of-Care Ultrasonography: Image Acquisition and Assessment.

Frailty is a significant predictor of a range of adverse outcomes in surgical patients, including increased mechanical ventilation time, longer hospital stays, unplanned readmissions, stroke, delirium, and death. However, accessible tools for screening in clinical settings are limited. Computed tomography of the psoas muscle is the current standard imaging device for measuring frailty, but it is expensive, time-consuming, and exposes the patient to ionizing radiation. Recently, the use of point-of-care ultrasound (POCUS) has emerged as a potential tool to determine the presence of frailty and has been shown to accurately predict frailty and postoperative outcomes. In this article, we will describe the image acquisition of the quadriceps muscles and explain how they can be used to determine frailty and predict postoperative adverse events. We will present information on probe selection, patient positioning, and troubleshooting. Images from a demonstration will be used to present the POCUS technique and example results. The article will culminate in a discussion of the use of these images in medical decision-making and potential limitations.

Clinical and Analytical Performance of a Novel Point-of-Care High-Sensitivity Cardiac Troponin I Assay.

BACKGROUND: Point-of-care (POC) high-sensitivity cardiac troponin assays may further accelerate the diagnosis of myocardial infarction (MI). OBJECTIVES: This study sought to assess the clinical and analytical performance of the novel high-sensitivity cardiac troponin I (hs-cTnI)-SPINCHIP POC test. METHODS: Adult patients presenting with acute chest discomfort to the emergency department were enrolled in an international, diagnostic, multicenter study. The final diagnosis was centrally adjudicated by 2 independent cardiologists using all clinical information. We compared the discriminatory performance of hs-cTnI-SPINCHIP with current established central laboratory assays and derived an assay-specific hs-cTnI-SPINCHIP 0/1-hour algorithm. Secondary analyses included sample type comparisons (whole blood, fresh/frozen plasma, and capillary finger prick) and precision analysis. RESULTS: MI was the adjudicated final diagnosis in 214 (19%) of 1,102 patients. Area under the receiver-operating characteristic curve was 0.94 (95% CI: 0.92-0.95) for hs-cTnI-SPINCHIP vs 0.94 (95% CI: 0.92-0.95) for hs-cTnI-Architect (P = 0.907) and 0.93 (95% CI: 0.91-0.95) for high-sensitivity cardiac troponin T Elecsys (P = 0.305). A cutoff <7 ng/L at presentation (if chest pain onset was >3 hours) or <7 ng/L together with a 0/1-hour delta of <4 ng/L ruled out 51% with a sensitivity and negative predictive value of 100% (95% CI: 97.7%-100%) and 100% (95% CI: 99.0%-100%), respectively. A hs-cTnI-SPINCHIP concentration ≥36 ng/L or a 0/1-hour delta ≥11 ng/L ruled in 27% with a specificity and positive predictive value of 90.9% (95% CI: 88.3%-92.9%) and 72.9% (95% CI: 66.4%-78.6%), respectively. Bootstrap internal validation confirmed excellent diagnostic performance. High agreement was observed between different sample types. CONCLUSIONS: The SPINCHIP hs-cTnI POC test has very high diagnostic accuracy. Its assay-specific 0/1-hour algorithm achieved very high sensitivity/negative predictive value and specificity/positive predictive value for rule-out/in MI. (Advantageous Predictors of Acute Coronary Syndromes Evaluation [APACE] Study [APACE]; NCT00470587).

Evaluation of left ventricular ejection fraction by a new automatic tool on a pocket ultrasound device: Concordance study with cardiac magnetic resonance imaging.

INTRODUCTION: Assessment of left ventricular ejection fraction (LVEF) is one of the primary objectives of echocardiography. The gold standard assessment technique in emergency medicine is eyeballing. A new tool is now available on pocket ultrasound devices (PUD): automatic LVEF. The primary aim of this study was to evaluate the concordance between LVEF values estimated by automatic LVEF with PUD and by cardiac magnetic resonance imaging (MRI). MATERIALS: This was a prospective, monocentric, and observational study. All adult patients with an indication for cardiac MRI underwent a point-of-care ultrasound. Blinded to the MRI results, the emergency physician assessed LVEF using the automatic PUD tool and by visual evaluation. RESULTS: Sixty patients were included and analyzed. Visual estimation of LVEF was feasible for all patients and automatic evaluation for 52 (87%) patients. Lin's concordance correlation coefficient between automatic ejection fraction with PUD and by cardiac MRI was 0.23 (95% CI, 0.03-0.40). CONCLUSION: Concordance between LVEF estimated by the automatic ejection fraction with PUD and LVEF estimated by MRI was non-existent.

Development of Aptamer-Functionalized Gold Nanoparticles as Probes in Point-of-Care Diagnostic Device for Rapid Detection of Multidrug-Resistant Bacteria in Bombyx mori L. .

The sericulture industry suffers severe crop losses due to various silkworm diseases, necessitating the development of further technologies for rapid pathogen detection. Here, we report an all-in-one portable biosensor that combines conjugated gold nanoparticles (Au NPs) with an aptamer-based lateral flow assay (LFA) platform for the real-time analysis of Mammaliicoccus sp. and Pseudomonas sp. Our platform enables sample-to-answer naked eye detection within 5 min without any cross-reactivity with other representatives of the silkworm pathogenic bacterial group. This assay was based on the sandwich-type format using a bacteria-specific primary aptamer (Apt1) conjugated with 23 nm ± 1.27 nm Au NPs as a signal probe and another bacteria-specific secondary aptamer (Apt2)-coated nitrocellulose membrane as a capture probe. The hybridization between the signal probe and the capture probe in the presence of bacteria develops a red band in the test line, whose intensity is directly proportional to the bacterial concentration. Under the optimal experimental conditions, the visual limit of detection of the strip for Mammaliicoccus sp. and Pseudomonas sp. was 1.5 × 104 CFU/mL and 1.5 × 103 CFU/mL, respectively. Additionally, the performance of the LFA device was validated by using a colorimetric assay, and the results from the colorimetric assay are consistent with those obtained from the LFA. Our findings indicate that the developed point-of-care diagnostic device has significant potential for providing a cost-effective, scalable alternative for the rapid detection of silkworm pathogens.

Economics of reducing response time to foreign-animal disease in the United States with point-of-care diagnostic tests.

BACKGROUND: As low probability events, United States producers, value chain actors, and veterinary services (VS) have limited experience with identifying foreign animal disease (FAD), which can allow FADs to spread undetected. Point-of-care (POC) diagnostic testing may help reduce the time from detecting an initial suspect case to implementing actionable interventions compared to the current approach of only using laboratory diagnostic testing for disease diagnosis and confirmation. To evaluate the value of the reduced response time, we compare the associated costs between the two diagnostic approaches while accounting for the uncertainty surrounding the size of a FAD event. METHODS: We apply a state-contingent approach (SCA) to model the uncertainty surrounding a FAD through alternative events, where the event defines the scale of outbreak size and its duration. We apply this approach within a cost-benefit framework (CBA) to determine the economic value from the two testing investment strategies to help explain the policymaker's response (and costs) to alternative FAD events while also considering the cost impacts on the producers from each event. RESULTS: Compared to the current laboratory strategy, a POC strategy that reduces response time by 0.5-days (swine, cattle scenarios) and 1.5-days (poultry scenario) may provide cost-saving to both producers and public response efforts. The benefit-cost analysis further suggests that despite the higher fixed costs to adopt the POC strategy, the swine and cattle sectors may benefit while the benefits may not be as pronounced in the poultry sector. DISCUSSION: POC testing that can reduce the time between detection and response during a FAD event may be a sound strategy for public expenditure and provide cost-savings for producers, especially when minimal fixed costs are incurred. However, to fully determine the value of POC testing, the consequences (costs) associated with potential actions if something goes wrong, (e.g. false positive results), should be considered in future studies.

Rapid detection of SARS-CoV-2 with a mobile device based on pulse controlled amplification.

In the past, vast research has been conducted on biosensors and point-of-care (PoC) diagnostics. Despite rapid advances especially during the SARS-CoV-2 pandemic in this research field a low-cost molecular biosensor exhibiting the user-friendliness of a rapid antigen test, and also the sensitivity and specificity of a PCR test, has not been developed yet. To this end we developed a novel microfluidics based and handheld PoC device, that facilitates viral detection at PCR sensitivity and specificity in less than 40 min, including 15 min sample preparation. This was attained by incorporation of pulse controlled amplification (PCA), a method which uses short electrical pulses to rapidly increase the temperature of a small fraction of the sample volume. In this work, we present a low-cost PCA device with a microfluidic consumable intended for the use in a decentralized or home-setting. We used finite element analysis (FEA) simulations to display the fundamental principle and highlight the critical parameter dependency of PCA, such as pulse length and resistor shape. Furthermore, we integrated a simple and fast workflow for sample preparation and evaluated the limit of detection (LoD) for SARS-CoV-2 viral RNA, which is 0.88 copies/µL (=44 copies/reaction), and thus, comparable to conventional RT-qPCR. Additionally, target specificity of the device was validated. Our device and PCA approach enables cost-effective, rapid and mobile molecular diagnostics while remaining highly sensitive and specific.

Colorimetric detection of serum creatinine on a miniaturized platform using hue-saturation-value space analysis.

Chronic kidney disease (CKD) is a widespread condition with considerable health and economic impacts globally. However, existing methodologies for serum creatinine assessment often involve prolonged wait times and sophisticated equipment, such as spectrometers, hindering real-time diagnosis and care. Innovative solutions like point-of-care (POC) devices are emerging to address these challenges. In this context, there is a recognized need for remote, regular, automated, and low-cost analysis of serum creatinine levels, given its role as a critical parameter for CKD diagnosis and management. This study introduces a miniaturized system with integrated heater elements designed for precise serum creatinine measurement. The system operates based on the Jaffe method and accurate serum creatinine measurement within a microreservoir chip. Smartphone-based image processing using the hue-saturation-value (HSV) color space was applied to captured images of microreservoirs. The creatinine analyses were conducted in serum with a limit of detection of ~ 0.4 mg/dL and limit of quantification of ~ 1.3 mg/dL. Smartphone-based image processing employing the HSV color space outperformed spectrometric analysis for creatinine measurement conducted in serum. This pioneering technology and smartphone-based processing offer the potential for decentralized renal function testing, which could significantly contribute to improved patient care. The miniaturized system offers a low-cost alternative ($87 per device), potentially reducing healthcare expenditures (~ $0.5 per test) associated with CKD diagnosis and management. This innovation could greatly improve access to diagnosis and monitoring of CKD, especially in regions where access to sophisticated laboratory equipment is limited.

First insights of integrating the Bonn Internship Curriculum for Point-of-Care Ultrasound (BI-POCUS): progress and educational aspects.

BACKGROUND: Point-of-care ultrasound (POCUS) is rapidly gaining prominence in various clinical settings. As its use becomes more widespread, there is a growing need for comprehensive ultrasound training in medical education to ensure that future healthcare professionals are proficient in this essential diagnostic tool. OBJECTIVE: This study is the first attempt by the University of Bonn to seamlessly integrate ultrasound courses and the use of ultrasound devices into the regular activities of final year medical students and to evaluate the usage of these devices. METHODS: A total of forty students in their practical year were provided with a hendheld ultrasound device for a period of four months. During this time, they were invited to take part in eight optional ultrasound courses in which they acquired images and those images were rated using a specially developed rating system. At the end of the tertial, students were able to take part in a voluntary survey on the use of the equipment. RESULTS: Participation in the optional ultrasound courses was well received, with the Introduction and FAST module drawing the largest number of participants (29). Among the ultrasound images acquired by students, those of the lungs obtaining the highest rating, with 18.82 (SD ± 4.30) points out of 23 points, while the aorta and vena cava images scored lowest, with an average of 16.62 (SD ± 1.55) points. The overall mean score for all images was 17.47 (SD ± 2.74). Only 21 students responded to the survey. Of the participating students, 67% used the device independently four times or fewer during the tertial. CONCLUSION: The study aimed to enhance the BI-POCUS curriculum by improving students' ultrasound skills during their practical year. However, device usage was lower than expected, with most students using it only once a month or less. This raises concerns about the justification of the effort and resources. Future initiatives will focus on technical improvements, better login data provision, and closer monitoring of usage and progress, emphasizing the need for practical ultrasound training in medical education.

Point-of-Care Multiplex Detection of Respiratory Viruses.

The COVID-19 pandemic, in addition to the co-occurrence of influenza virus and respiratory syncytial virus (RSV), has emphasized the requirement for efficient and reliable multiplex diagnostic methods for respiratory infections. While existing multiplex detection techniques are based on reverse transcription quantitative polymerase chain reaction (RT-qPCR) and extraction and purification kits, the need for complex instrumentation and elevated cost limit their scalability and availability. In this study, we have developed a point-of-care (POC) device based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) that can simultaneously detect four respiratory viruses (SARS-CoV-2, Influenza A, Influenza B, and RSV) and perform two controls in less than 30 min, while avoiding the use of the RNA extraction kit. The system includes a disposable microfluidic cartridge with mechanical components that automate sample processing, with a low-cost and portable optical reader and a smartphone app to record and analyze fluorescent images. The application as a real point-of-care platform was validated using swabs spiked with virus particles in nasal fluid. Our portable diagnostic system accurately detects viral RNA specific to respiratory pathogens, enabling deconvolution of coinfection information. The detection limits for each virus were determined using virus particles spiked in chemical lysis buffer. Our POC device has the potential to be adapted for the detection of new pathogens and a wide range of viruses by modifying the primer sequences. This work highlights an alternative approach for multiple respiratory virus diagnostics that is well-suited for healthcare systems in resource-limited settings or at home.

Performance evaluation and characterization of pre-analytical effects by sample types and storage conditions on tumor marker measurement by the point-of-care test platform IchromaTM II.

Tumor markers should be measured regularly and accurately to prevent, diagnose, and monitor cancers efficiently. We aimed to characterize the pre-analytical factors effecting on the analytical performance of point-of-care test (POCT) platform IchromaTM II (Boditech Med Inc., Gangwon-do, Korea) for alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and prostate specific antigen (PSA) and evaluate their consequences in clinical practice. Based on comprehensive evaluation for the analytical performance of IchromaTM II including precision, linearity, and method comparison performed according to CLSI guidelines, pre-analytical factors of sample types and conditions were extensively analyzed. A total of five sample types [serum, plasma (PL) and whole blood (WB) from EDTA tube, PL and WB from sodium heparin tube] from 40 patients were used for comparing among specimen types. Additionally, stability was assessed up to 21 h at room temperature, refrigerated for 8 days, and frozen for 16 weeks by using 4 levels of pooled patient samples which were measured in triplicate. Precision, linearity and correlation with central laboratory analyzers observed in all three tumor markers were within acceptable criteria. However, variable degrees of percent deviations were observed according to sample type and storage conditions. Only EDTA PL samples presented clinically acceptable percentage biases for all three tumor markers when stored at room temperature or refrigerated condition. Positive bias of CEA and PSA in storage duration until 16 weeks were observed when stored in frozen condition. While IchromaTM II showed an adequate analytical performance as a POCT platform with simple operating procedures for the measurement of tumor markers, clinical laboratories should be aware of stability issues when different types of blood specimens are practically utilized.

[POCUS in the emergency department: some nervous system applications]. / POCUS aux urgences : quelques applications en lien avec le système nerveux.

Point of care ultrasound (POCUS) is used daily to diagnose and treat patients in emergency medicine. This article aims to demonstrate its utility focusing on central and peripheric nervous system pathologies frequently encountered in the emergency department such as difficult lumbar puncture, pain relief for proximal fracture of the femur and the detection of intracranial hypertension. Taught by well trained professionals the learning curve for performing these interventions safely is quick. The developmental potential for peripheral nerve blocks in emergency departments is high, especially for the fascia iliaca block.

Le POCUS (point of care ultrasound) est utilisé quotidiennement dans les services d'urgences à des fins diagnostiques et thérapeutiques. Cet article a pour but de démontrer son utilité dans quelques situations cliniques rencontrées fréquemment aux urgences en lien avec les systèmes nerveux central et périphérique, à savoir la ponction lombaire difficile, l'antalgie lors de fracture du fémur proximal et la détection d'une hypertension intracrânienne. Au contact de personnes formées, la courbe d'apprentissage pour réaliser ces gestes en toute sécurité est rapide. Un fort potentiel de développement existe pour la réalisation des blocs nerveux périphériques dans les services d'urgences, en particulier pour le bloc iliofascial.