Improving assay feasibility and biocompatibility of 3D cyclic olefin copolymer microwells by superhydrophilic modification via ultrasonic spray deposition of polyvinyl alcohol.

Sample partitioning is a crucial step towards digitization of biological assays on polymer microfluidic platforms. However, effective liquid filling into microwells and long-term hydrophilicity remain a challenge in polymeric microfluidic devices, impeding the applicability in diagnostic and cell culture studies. To overcome this, a method to produce permanent superhydrophilic 3-dimensional microwells using cyclic olefin copolymer (COC) microfluidic chips is presented. The COC substrate is oxidized using UV treatment followed by ultrasonic spray coating of polyvinyl alcohol solution, offering uniform and long-term coating of high-aspect ratio microfeatures. The coated COC surfaces are UV-cured before bonding with a hydrophobic pressure-sensitive adhesive to drive selective filling into the wells. The surface hydrophilicity achieved using this method remains unchanged (water contact angle of 9°) for up to 6 months and the modified surface is characterized for physical (contact angle & surface energy, morphology, integrity of microfeatures and roughness), chemical composition (FTIR, Raman spectroscopy) and coating stability (pH, temperature, time). To establish the feasibility of the modified surface in biological applications, PVA-coated COC microfluidic chips are tested for DNA sensing (digital LAMP detection of CMV), and biocompatibility through protein adsorption and cell culture studies (cell adhesion, viability, and metabolic activity). Kidney and breast cells remained viable for the duration of testing (7 days) on this modified surface, and the coating did not affect the protein content, morphology or quality of the cultured cells. The ultrasonic spray coated system, coating with 0.25 % PVA for 15 cycles with 0.12 A current after UV oxidation, increased the surface energy of the COC (naturally hydrophobic) from 22.04 to 112.89 mJ/m2 and improved the filling efficiency from 40 % (native untreated COC) to 94 % in the microwells without interfering with the biocompatibility of the surface, proving to be an efficient, high-throughput and scalable method of microfluidic surface treatment for diagnostic and cell growth applications.

Inferior vena cava ultrasound to predict hypotension after general anesthesia induction: a systematic review and meta-analysis of observational studies.

PURPOSE: Hypotension after induction of general anesthesia is common and is associated with significant adverse events. Identification of patients at high risk can inform the use of preoperative mitigation strategies. We conducted a systematic review and meta-analysis to assess the diagnostic accuracy of the inferior vena cava collapsibility index (IVC-CI) and maximal diameter (dIVCmax) in predicting postinduction hypotension and to identify their predictive performance across different threshold ranges. METHODS: We searched MEDLINE, PubMed®, and Embase from inception to March 2023 for prospective observational studies exploring the performance of IVC-CI and dIVCmax in predicting postinduction hypotension in adults presenting for elective surgery under general anesthesia. We excluded studies reporting on IVC parameters predicting postinduction hypotension in the obstetric patient population or exclusively in patients with obesity. Trials screening and data extraction were conducted independently. We performed meta-analyses to identify the performance of IVC parameters in predicting postinduction hypotension, followed by subgroup analyses that sought the IVC-CI range with the highest hierarchical summary receiver-operating characteristic area under the curve (HSROC-AUC). We used a bivariate random effects model to calculate summary estimates. We evaluated study quality using Newcastle-Ottawa scores and certainty of evidence using the GRADE framework. RESULTS: We included 14 studies involving 1,166 patients. Pooled sensitivity and specificity of the IVC-CI to predict postinduction hypotension was 0.68 (95% confidence interval [CI], 0.55 to 0.79; coverage probability, 0.91) and 0.78 (95% CI, 0.69 to 0.85; coverage probability, 0.9), respectively, with an HSROC-AUC of 0.80 (95% CI, 0.68 to 0.85, high quality of evidence). An IVC-CI threshold range of 40-45% had an HSROC-AUC of 0.86 (95% CI, 0.69 to 0.93, high quality of evidence). CONCLUSIONS: Preoperative IVC-CI is a strong predictor of postinduction hypotension. We recommend that future studies use an IVC-CI threshold of 40-45% (low certainty of evidence). Future studies are needed to establish whether ultrasound-guided preoperative optimization improves outcomes in high-risk patients. STUDY REGISTRATION: PROSPERO ( CRD42022316140 ); first submitted 10 March 2022.

RéSUMé: OBJECTIF: L'hypotension après l'induction de l'anesthésie générale est fréquente et est associée à des effets indésirables importants. L'identification des patient•es à haut risque peut éclairer l'utilisation de stratégies préopératoires d'atténuation. Nous avons réalisé une revue systématique et une méta-analyse pour évaluer la précision diagnostique de l'indice de collapsibilité de la veine cave inférieure (IC-VCI) et du diamètre maximal (dVCImax) pour prédire l'hypotension post-induction et identifier leurs performances prédictives dans différentes plages de seuils. MéTHODE: Nous avons fait des recherches dans les bases de données MEDLINE, PubMed® et Embase de leur création jusqu'en mars 2023 pour en extraire les études observationnelles prospectives explorant les performances de l'IC-VCI et du dVCImax pour la prédiction de l'hypotension post-induction chez des adultes se présentant pour une chirurgie non urgente sous anesthésie générale. Nous avons exclu les études rapportant des paramètres de VCI prédisant l'hypotension post-induction dans la population obstétricale ou exclusivement chez des personnes obèses. Le tri des études et l'extraction des données ont été menés indépendamment. Nous avons réalisé des méta-analyses pour identifier la performance des paramètres de VCI dans la prédiction de l'hypotension post-induction, suivies d'analyses de sous-groupes qui ont recherché la plage d'IC-VCI avec le plus haut niveau de hiérarchie de l'aire sous la courbe de la courbe ROC (HSROC-AUC). Nous avons utilisé un modèle bivarié à effets aléatoires pour calculer des estimations sommaires. Nous avons évalué la qualité des études à l'aide des scores de Newcastle-Ottawa et la certitude des données probantes à l'aide de l'outil GRADE. RéSULTATS: Quatorze études portant sur 1166 patient·es ont été incluses. La sensibilité et la spécificité combinées de l'IC-VCI pour prédire l'hypotension post-induction étaient de 0,68 (intervalle de confiance [IC] à 95 %, 0,55 à 0,79; probabilité de couverture, 0,91) et 0,78 (IC 95 %, 0,69 à 0,85; probabilité de couverture, 0,9), respectivement, avec une HSROC-AUC de 0,80 (IC 95 %, 0,68 à 0,85, données probantes de haute qualité). Une plage de seuils d'IC-VCI de 40 à 45 % avait une HSROC-AUC de 0,86 (IC 95 %, 0,69 à 0,93, haute qualité des données probantes). CONCLUSION: L'IC-VCI préopératoire est un bon prédicteur de l'hypotension post-induction. Nous recommandons que les études futures utilisent un seuil d'IC-VCI de 40 à 45 % (faible certitude des données probantes). De futures études sont nécessaires pour déterminer si l'optimisation préopératoire échoguidée améliore les devenirs chez la patientèle à risque élevé. ENREGISTREMENT DE L'éTUDE: PROSPERO ( CRD42022316140 ); première soumission le 10 mars 2022.

Revolutionary Point-of-Care Wearable Diagnostics for Early Disease Detection and Biomarker Discovery through Intelligent Technologies.

Early-stage disease detection, particularly in Point-Of-Care (POC) wearable formats, assumes pivotal role in advancing healthcare services and precision-medicine. Public benefits of early detection extend beyond cost-effectively promoting healthcare outcomes, to also include reducing the risk of comorbid diseases. Technological advancements enabling POC biomarker recognition empower discovery of new markers for various health conditions. Integration of POC wearables for biomarker detection with intelligent frameworks represents ground-breaking innovations enabling automation of operations, conducting advanced large-scale data analysis, generating predictive models, and facilitating remote and guided clinical decision-making. These advancements substantially alleviate socioeconomic burdens, creating a paradigm shift in diagnostics, and revolutionizing medical assessments and technology development. This review explores critical topics and recent progress in development of 1) POC systems and wearable solutions for early disease detection and physiological monitoring, as well as 2) discussing current trends in adoption of smart technologies within clinical settings and in developing biological assays, and ultimately 3) exploring utilities of POC systems and smart platforms for biomarker discovery. Additionally, the review explores technology translation from research labs to broader applications. It also addresses associated risks, biases, and challenges of widespread Artificial Intelligence (AI) integration in diagnostics systems, while systematically outlining potential prospects, current challenges, and opportunities.

Effect of Departmental and Physician-Selected Interventions on Point-of-Care Ultrasound Documentation Completion.

Background Point-of-care ultrasound (POCUS) has been disruptive to many experienced emergency physicians as it requires competence in a new physical skill, real-time image interpretation, and navigation of novel software for submission to the electronic health record (EHR). Incomplete documentation of a performed POCUS study used for clinical decision-making represents a potential medicolegal liability, may expose the patient to repetitive or potentially unnecessary imaging, and is a missed opportunity for reimbursement. Identifying effective facilitators of ED POCUS documentation completion requires additional investigation. Methods In the first part of this mixed-methods study, eligible attending physicians were stratified into levels of use ("high"/"low"/"never") based on recent POCUS documentation performance. Semi-structured interviews were conducted with high and low utilizers to explore their perceptions of the POCUS submission workflow and their receptivity to various proposed interventions. Qualitative data were analyzed using a thematic analysis that explored perceived usefulness and usability. The second part of the study consisted of two intervention phases. First, physicians achieving minimum POCUS documentation numbers were rewarded with additional shift scheduling flexibility. In the second phase, the intervention that garnered the most interview support, daily documentation reminder emails, was implemented. The primary outcome was the individual POCUS documentation rates calculated as all studies submitted divided by all studies performed (submitted plus unsubmitted) per month. Provider-level monthly data was aggregated into a departmental rate. Results Interviews were conducted with 12 physicians, six from the highest and six from the lowest documentation quartiles. Both groups supported the same two proposed interventions: reminder emails ranked first, then monetary rewards ranked second. High utilizers emphasized the clinical utility of POCUS, whereas low utilizers expressed concerns over "double billing" and exposure to medicolegal liability with uncertain scan interpretations. For low utilizers, a documentation decision could be dependent on the performing resident physician's displayed confidence. Both groups voiced frustration with the need to use a separate program, Qpath (Telexy Healthcare, Inc, Maple Ridge, British Columbia, Canada), for POCUS documentation. During intervention phase one, the aggregate departmental documentation rate increased from 44.6% to 60.1% with the introduction of the schedule request incentive. This improvement was seen across all documentation quartiles. The departmental rate remained stable and did not improve further following the addition of the daily documentation reminder emails in intervention phase two. When reminder emails ceased yet the day-off request incentive continued, the departmental rate did not drop. Conclusions The implementation of a non-financial shift scheduling incentive correlated with the largest increase in departmental POCUS documentation rate. Interviewees incorrectly predicted that email reminders would be the most influential intervention highlighting a mismatch between physician perception and effective drivers of behavior change. Further investigation may focus on determining the size and longevity of the isolated impact of a schedule request incentive, as one might expect diminishing marginal utility.

Co-crosslinking strategy for dual functionalization of small magnetic nanoparticles with redox probes and biological probes.

Surface functionalization strategy is becoming a crucial bridge from magnetic nanoparticles (MNPs) to their broad bio-application. To realize the multiple functions of MNPs such as magnetic manipulation, target capture, and signal amplification in their use of electrochemical biosensing, co-crosslinking strategy was proposed here to construct dual-functionalized MNPs by combining ultra-sensitive redox moieties and specific biological probes. In this work, MNPs with a TEM size of 10 nm were synthesized by co-precipitation for amination and PEGylation to maintain colloid stability once dispersed in high-ionic-strength buffer (such as phosphate-buffered saline). Then, MNPs@IgG were prepared via the bis(sulfosuccinimidyl) suberate (BS3) cross-linker to conjugate these IgG onto the MNP surface, with a binding efficiency of 73%. To construct dual-functionalized MNPs, these redox probes of ferrocene-NHS (Fc) were co-crosslinked onto the MNP surface, together with IgG, by using BS3. The developed MNPs@Redox@IgG were characterized by SDS‒PAGE to identify IgG binding and by square wave voltammetry (SWV) to validate the redox signal. Additionally, the anti-CD63 antibodies were selected for the development of MNPs@anti-CD63 for use in the bio-testing of exosome sample capture. Therefore, co-crosslinking strategy paved a way to develop dual-functionalized MNPs that can be an aid of their potential utilization in diagnostic assay or electrochemical methods.

CRISPR-based electrochemical biosensors: an alternative for point-of-care diagnostics?

The combination of CRISPR technology and electrochemical sensors has sparked a paradigm shift in the landscape of point-of-care (POC) diagnostics. This review explores the dynamic convergence between CRISPR and electrochemical sensing, elucidating their roles in rapid and precise biosensing platforms. CRISPR, renowned for its remarkable precision in genome editing and programmability capability, has found a novel application in conjunction with electrochemical sensors, promising highly sensitive and specific detection of nucleic acids and biomarkers associated with diverse diseases. This article navigates through fundamental principles, research developments, and applications of CRISPR-based electrochemical sensors, highlighting their potential to revolutionize healthcare accessibility and patient outcomes. In addition, some key points and challenges regarding applying CRISPR-powered electrochemical sensors in real POC settings are presented. By discussing recent advancements and challenges in this interdisciplinary field, this review evaluates the potential of these innovative sensors as an alternative for decentralized, rapid, and accurate POC testing, offering some insights into their applications across clinical scenarios and their impact on the future of diagnostics.

Impact of point-of-care gonorrhea and chlamydia testing in the emergency department on reducing overtreatment rates.

BACKGROUND: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections continue to increase in the United States. Advancement in technology with point-of-care (POC) testing can improve the overall treatment of sexually transmitted infections (STI) in the emergency department (ED) by shortening the time to test result and administration of accurate treatment. The purpose of this study was to assess if the POC test reduced the rate of overtreatment for CT and/or NG compared to the standard-of-care (SOC) test. METHODS: This retrospective cohort study included adult patients tested for CT and NG at two urban EDs between August 2020 and October 2022. This cohort excluded hospital admissions, elopement, pregnancy, rectal and oral samples, victims of sexual assault, and diagnoses for which antimicrobial treatment overlapped that of CT/NG. The primary outcome assessed overtreatment, defined as receiving treatment in the ED or a prescription prior to discharge for patients who tested negative for CT and/or NG. Secondary outcomes included undertreatment rates, overtreatment rates in select populations, test turnaround time, and ED length of stay (LOS). RESULTS: Of 327 patients screened, 97 patients were included in the SOC group and 100 in POC. Overtreatment for CT was provided in zero POC patients and 29 (29.9%) SOC patients (p < 0.001). NG was overtreated in 1 (1%) POC and 23 (23.7%) SOC (p < 0.001). POC was associated with undertreatment of CT and/or NG in two patients, compared to four patients tested with SOC. Overall, treatment was deemed inappropriate for 5 (5%) of those tested with POC, compared to 35 (36%) tested with SOC (p < 0.001). There was no difference in ED LOS (2.7 vs 3.01 h, p = 0.41). CONCLUSIONS: POC testing facilitated the return of results prior to patients being discharged from the ED. Compared to standard testing, POC improved appropriateness of CT and NG treatment by reducing the rates of overtreatment.

Fluid Responsiveness and Management in Obstetrics using Point-of-Care Ultrasound.

Fluid management in obstetric care is crucial due to the complex physiological conditions of pregnancy, which complicate clinical manifestations and fluid balance management. This expert review examines the use of point-of-care ultrasound (POCUS) to evaluate and monitor the response to fluid therapy in pregnant patients. Pregnancy induces significant physiological changes, including increased cardiac output and glomerular filtration rate, decreased systemic vascular resistance, and plasma oncotic pressure. Conditions like preeclampsia further complicate fluid management due to decreased intravascular volume and increased capillary permeability. Traditional methods of assessing fluid volume status, such as physical examination and invasive monitoring, are often unreliable or inappropriate. POCUS provides a non-invasive, rapid, and reliable means to assess fluid responsiveness, which is essential in managing fluid therapy in pregnant patients. This review details various POCUS modalities used to measure dynamic changes in fluid status, focusing on the evaluation of the inferior vena cava (IVC), lung ultrasound (Lung US), and the left ventricular outflow tract (LVOT). IVC ultrasound in spontaneously breathing patients determines diameter variability, predicting fluid responsiveness and being feasible even late in pregnancy. Lung ultrasound is critical for detecting early signs of pulmonary edema before clinical symptoms arise and is more accurate than traditional radiography. The LVOT velocity-time integral (VTI) assesses stroke volume response to fluid challenges, providing a quantifiable measure of cardiac function, especially beneficial in critical care settings where rapid and accurate fluid management is essential. The expert review synthesizes current evidence and practice guidelines, suggesting integrating POCUS as a fundamental aspect of fluid management in obstetrics. It calls for ongoing research to enhance techniques and validate their use in broader clinical settings, aiming to improve outcomes for pregnant patients and their babies by preventing complications associated with both under- and over-resuscitation.

Gamified Crowdsourcing as a Novel Approach to Lung Ultrasound Data Set Labeling: Prospective Analysis.

BACKGROUND: Machine learning (ML) models can yield faster and more accurate medical diagnoses; however, developing ML models is limited by a lack of high-quality labeled training data. Crowdsourced labeling is a potential solution but can be constrained by concerns about label quality. OBJECTIVE: This study aims to examine whether a gamified crowdsourcing platform with continuous performance assessment, user feedback, and performance-based incentives could produce expert-quality labels on medical imaging data. METHODS: In this diagnostic comparison study, 2384 lung ultrasound clips were retrospectively collected from 203 emergency department patients. A total of 6 lung ultrasound experts classified 393 of these clips as having no B-lines, one or more discrete B-lines, or confluent B-lines to create 2 sets of reference standard data sets (195 training clips and 198 test clips). Sets were respectively used to (1) train users on a gamified crowdsourcing platform and (2) compare the concordance of the resulting crowd labels to the concordance of individual experts to reference standards. Crowd opinions were sourced from DiagnosUs (Centaur Labs) iOS app users over 8 days, filtered based on past performance, aggregated using majority rule, and analyzed for label concordance compared with a hold-out test set of expert-labeled clips. The primary outcome was comparing the labeling concordance of collated crowd opinions to trained experts in classifying B-lines on lung ultrasound clips. RESULTS: Our clinical data set included patients with a mean age of 60.0 (SD 19.0) years; 105 (51.7%) patients were female and 114 (56.1%) patients were White. Over the 195 training clips, the expert-consensus label distribution was 114 (58%) no B-lines, 56 (29%) discrete B-lines, and 25 (13%) confluent B-lines. Over the 198 test clips, expert-consensus label distribution was 138 (70%) no B-lines, 36 (18%) discrete B-lines, and 24 (12%) confluent B-lines. In total, 99,238 opinions were collected from 426 unique users. On a test set of 198 clips, the mean labeling concordance of individual experts relative to the reference standard was 85.0% (SE 2.0), compared with 87.9% crowdsourced label concordance (P=.15). When individual experts' opinions were compared with reference standard labels created by majority vote excluding their own opinion, crowd concordance was higher than the mean concordance of individual experts to reference standards (87.4% vs 80.8%, SE 1.6 for expert concordance; P<.001). Clips with discrete B-lines had the most disagreement from both the crowd consensus and individual experts with the expert consensus. Using randomly sampled subsets of crowd opinions, 7 quality-filtered opinions were sufficient to achieve near the maximum crowd concordance. CONCLUSIONS: Crowdsourced labels for B-line classification on lung ultrasound clips via a gamified approach achieved expert-level accuracy. This suggests a strategic role for gamified crowdsourcing in efficiently generating labeled image data sets for training ML systems.

Examining barriers to antiretroviral therapy initiation in infants living with HIV in sub-Saharan Africa despite the availability of point-of-care diagnostic testing: a narrative systematic review.

INTRODUCTION: Antiretroviral therapy (ART) initiation in infants living with HIV before 12 weeks of age can reduce the risk of mortality by 75%. Point-of-care (POC) diagnostic testing is critical for prompt ART initiation; however, despite its availability, rates of ART initiation are still relatively low before 12 weeks of age. This systematic review describes the barriers to ART initiation in infants before 12 weeks of age, despite the availability of POC. METHODS: This systematic review used a narrative synthesis methodology. We searched PubMed and Scopus using search strategies that combined terms of multiple variants of the keywords "early infant initiation on antiretroviral therapy," "barriers" and "sub-Saharan Africa" (initial search 18th January 2023; final search 1st August 2023). We included qualitative, observational and mixed methods studies that reported the influences of early infant initiation on ART. We excluded studies that reported influences on other components of the Prevention of Mother to Child Transmission cascade. Using a deductive approach guided by the updated Consolidated Framework of Implementation Research, we developed descriptive codes and themes around barriers to early infant initiation on ART. We then developed recommendations for interventions for the identified barriers using the action, actor, target and time framework from the codes. RESULTS: Of the 266 abstracts reviewed, 52 full-text papers were examined, of which 12 papers were included. South Africa had most papers from a single country (n = 3) and the most reported study design was retrospective (n = 6). Delays in ART initiation beyond 12 weeks in infants 0-12 months were primarily associated with health facility and maternal factors. The most prominent barriers identified were inadequate resources for POC testing (including human resources, laboratory facilities and patient follow-up). Maternal-related factors, such as limited male involvement and maternal perceptions of treatment and care, were also influential. DISCUSSION: We identified structural barriers to ART initiation at the health system, social and cultural levels. Improvements in the timely allocation of resources for POC testing operations, coupled with interventions addressing social and behavioural barriers among both mothers and healthcare providers, hold a promise for enhancing timely ART initiation in infants. CONCLUSIONS: This paper identifies barriers and proposes strategies for timely ART initiation in infants.

Effectiveness of HIV self-testing when offered within assisted partner services in Western Kenya (APS-HIVST Study): a cluster randomized controlled trial.

INTRODUCTION: Assisted partner services (APS) is an effective strategy for increasing HIV testing, new diagnosis, and linkage to care among sexual partners of people living with HIV (PLWH). APS can be resource intensive as it requires community tracing to locate each partner named and offer them testing. There is limited evidence for the effectiveness of offering HIV self-testing (HIVST) as an option for partner testing within APS. METHODS: We conducted a cluster randomized controlled trial comparing provider-delivered HIV testing (Standard APS) versus offering partners the option of provider-delivered testing or HIVST (APS+HIVST) at 24 health facilities in Western Kenya. Facilities were randomized 1:1 and we conducted intent-to-treat analyses using Poisson generalized linear mixed models to estimate intervention impact on HIV testing, new HIV diagnoses, and linkage to care. All models accounted for clustering at the clinic level and new diagnoses and linkage models were adjusted for individual-level age, sex, and income a priori. RESULTS: From March to December 2021, 755 index clients received APS and named 5054 unique partners. Among these, 1408 partners reporting a prior HIV diagnosis were not eligible for HIV testing and were excluded from analyses. Of the remaining 3646 partners, 96.9% were successfully contacted for APS and tested for HIV: 2111 (97.9%) of 2157 in the APS+HIVST arm and 1422 (95.5%) of 1489 in the Standard APS arm. In the APS+HIVST arm, 84.6% (1785/2111) tested via HIVST and 15.4% (326/2111) received provider-delivered testing. Overall, 16.7% of the 3533 who tested were newly diagnosed with HIV (APS+HIVST = 357/2111 [16.9%]; Standard APS = 232/1422 [16.3%]). Of the 589 partners who were newly diagnosed, 90.7% were linked to care (APS+HIVST = 309/357 [86.6%]; Standard APS = 225/232 [97.0%]). There were no significant differences between the two arms in HIV testing (relative risk [RR]: 1.02, 95% CI: 0.96-1.10), new HIV diagnoses (adjusted RR [aRR]: 1.03, 95% CI: 0.76-1.39) or linkage to care (aRR: 0.88, 95% CI: 0.74-1.06). CONCLUSIONS: There were no differences between APS+HIVST and Standard APS, demonstrating that integrating HIVST into APS continues to be an effective strategy for identifying PLWH by successfully reaching and HIV testing >95% of elicited partners, newly diagnosing with HIV one in six of those tested, >90% of whom were linked to care. CLINICAL TRIAL NUMBER: NCT04774835.

Facilitators, barriers, and changes in POCUS use: longitudinal follow-up after participation in a national point-of-care ultrasound training course in Japan.

BACKGROUND: POCUS training courses are effective at improving knowledge and skills, but few studies have followed learners longitudinally post-course to understand facilitators, barriers, and changes in POCUS use in clinical practice. We conducted a prospective observational study of physicians who attended 11 standardized POCUS training courses between 2017 and 2019 in Japan. Physicians who attended a standardized POCUS course were surveyed about their current frequency of POCUS use of the heart, lung, abdomen, and lower extremity veins, and perceived barriers and facilitators to POCUS use in clinical practice. RESULTS: Data were analyzed from 112 completed surveys (response rate = 20%). A majority of responding physicians were faculty (77%) in internal medicine (69%) affiliated with community hospitals (55%). The mean delay between course attendance and survey response was 50.3 months. A significant increase in POCUS use from < 1 to ≥ 1 time per week was seen for all organ systems after 50 months post-course (p < 0.01). Approximately half of course participants reported an increase in the frequency of cardiac (61%), lung (53%), vascular (44%), and abdominal (50%) ultrasound use. General facilitators of POCUS use were easy access to ultrasound machines (63%), having a colleague with whom to learn POCUS (47%), and adequate departmental support (46%). General barriers included lack of opportunities for POCUS training (47%), poor access to ultrasound machines (38%), and limited time for POCUS training (33%). In the group with increased POCUS usage, specific facilitators reported were enhanced POCUS knowledge, improved image acquisition skills, and greater self-confidence in performing POCUS. Conversely, the group without increased POCUS usage reported lack of supervising physicians, low confidence, and insufficient training opportunities as specific barriers. CONCLUSIONS: Approximately half of physicians reported an increase in cardiac, lung, vascular, and abdominal POCUS use > 4 years after attending a POCUS training course. In addition to improving access to ultrasound machines and training opportunities, a supportive local clinical environment, including colleagues to share experiences in learning POCUS and local experts to supervise scanning, is important to foster ongoing POCUS practice and implementation into clinical practice.

Serial paired arterial and jugular venous point-of-care values in dogs undergoing manual basic life support.

OBJECTIVE: To evaluate differences in point-of-care (POC) variables obtained from arterial and jugular venous blood in dogs undergoing manual basic life support (BLS) and report changes over time. DESIGN: Experimental study. SETTING: Small animal research facility. ANIMALS: Twenty-four purpose-bred research dogs. INTERVENTIONS: Dogs were anesthetized, and arterial catheters were placed before euthanasia. One minute after cardiopulmonary arrest, BLS consisting of manual chest compressions and ventilation delivered via endotracheal intubation, face mask, mouth-to-nose, or no ventilation was initiated. Paired arterial and jugular venous blood samples were obtained for POC testing before euthanasia (T0), at 3 minutes (T3), and at 6 minutes (T6) into BLS. MEASUREMENTS AND MAIN RESULTS: The association of POC variables with arterial or venous sample type while controlling for type of ventilation and sampling timepoint was determined using a generalized linear mixed model. Variables obtained from arterial and venous blood samples were compared over time using repeated measures ANOVA or Friedman test. Pao2, anion gap, potassium, chloride, glucose concentration, and PCV were significantly higher in arterial blood samples compared with venous samples (P < 0.03). By T6, arterial glucose concentration, arterial and venous base excess, venous pH, and plasma lactate, potassium, creatinine, bicarbonate, and sodium concentrations were significantly increased, and arterial and venous Po2, ionized calcium concentration, PCV, and total plasma protein concentration were significantly decreased from T0 (P < 0.05). CONCLUSIONS: Although statistically significant, arteriovenous differences and changes in POC blood variables during BLS were small and not clinically relevant over time. Given the challenges of arterial blood sampling, it may be reasonable to pursue venous blood sampling during CPR. Further studies in dogs undergoing BLS and advanced life support are needed to better understand the potential clinical role of POC testing during CPR.

Development of two novel on-site detection visualization methods for murine hepatitis virus based on the multienzyme isothermal rapid amplification.

Murine hepatitis virus (MHV) infection is one of the most prevalent types of mice infection in laboratory. MHV could cause death in mice and even interfere with the results in animal experiments. Herein, we developed two isothermal approaches based on the Multienzyme Isothermal Rapid Amplification (MIRA), for rapid detection of MHV in conserved M gene. We designed and screened several pairs of primers and probes and the isothermal fluorescence detector was applied for the exonuclease Ⅲ reverse transcription MIRA (exo-RT-MIRA) assay. To further simplify the workflow, the portable fluorescence visualization instrument, also as a palm-sized handheld system, was used for the naked-eye exo-RT-MIRA assay. The amplification temperature and time were optimized. The assay could be processed well at 42 °C 20 min for the exo-RT-MIRA and the naked-eye exo-RT-MIRA assay. The limit of detection (LoD) of the exo-RT-MIRA assay was 43.4 copies/µL. The LoD of the naked-eye exo-RT-MIRA assay was 68.2 copies/µL. No nonspecific amplifications were observed in the two assays. A total of 107 specimens were examined by qPCR and two assays developed. The experimental results statistical analysis demonstrated that the exo-RT-MIRA assay with the qPCR yielded sufficient agreement with a kappa value of 1.000 (p < 0.0001). The results also exhibited a good agreement (kappa value, 0.961) (p < 0.0001) between the naked-eye exo-RT-MIRA assay and the qPCR assay. In our study, the exo-RT-MIRA assay and the naked-eye exo-RT-MIRA assay presented the possibility of new methods in MHV point-of-testing diagnosis.

Multicenter validation study for automated left ventricular ejection fraction assessment using a handheld ultrasound with artificial intelligence.

We sought to validate the ability of a novel handheld ultrasound device with an artificial intelligence program (AI-POCUS) that automatically assesses left ventricular ejection fraction (LVEF). AI-POCUS was used to prospectively scan 200 patients in two Japanese hospitals. Automatic LVEF by AI-POCUS was compared to the standard biplane disk method using high-end ultrasound machines. After excluding 18 patients due to infeasible images for AI-POCUS, 182 patients (63 ± 15 years old, 21% female) were analyzed. The intraclass correlation coefficient (ICC) between the LVEF by AI-POCUS and the standard methods was good (0.81, p < 0.001) without clinically meaningful systematic bias (mean bias -1.5%, p = 0.008, limits of agreement ± 15.0%). Reduced LVEF < 50% was detected with a sensitivity of 85% (95% confidence interval 76%-91%) and specificity of 81% (71%-89%). Although the correlations between LV volumes by standard-echo and those by AI-POCUS were good (ICC > 0.80), AI-POCUS tended to underestimate LV volumes for larger LV (overall bias 42.1 mL for end-diastolic volume). These trends were mitigated with a newer version of the software tuned using increased data involving larger LVs, showing similar correlations (ICC > 0.85). In this real-world multicenter study, AI-POCUS showed accurate LVEF assessment, but careful attention might be necessary for volume assessment. The newer version, trained with larger and more heterogeneous data, demonstrated improved performance, underscoring the importance of big data accumulation in the field.

The use of diagnostic ultrasound by primary care physicians in Switzerland - a cross-sectional study.

BACKGROUND: Diagnostic ultrasound has become a bedside tool widely available to many primary care physicians (PCPs) in Europe. It is often used as point-of-care ultrasonography (POCUS) in this setting. In Switzerland, certain POCUS examinations are listed as learning objectives in existing ultrasound training programs (we defined these examinations as swissPOCUS = sPOCUS). Ultrasound performed by PCPs can lead to faster diagnostic workup and reduce referral to secondary care units. However, adequate training is crucial to guarantee high quality. To guide the development of ultrasound training programs for PCPs, this study explores the use of ultrasound in primary care in Switzerland. METHODS: This was a cross-sectional study. We invited PCPs from the Swiss practice-based research network "Sentinella" to collect data on the first 5 daily ultrasounds they ordered or performed themselves. Participating PCPs collected data for 3 months - divided into 4 groups to account for seasonal differences. RESULTS: Out of 188 PCPs invited, 81.9% provided data through an initial questionnaire. 46.8% provided data on 1616 ultrasounds. 56.5% of PCPs had access to ultrasound machines, while 29.8% had completed formal training. 77% of the reported ultrasounds were self-performed; 27% of the reported scans (35% of all self-performed scans) were performed by PCPs with incomplete or no formal training. The main areas of interest were the abdominal (57.9%) and the musculoskeletal (22%) region. 36.9% of reported examinations were sPOCUS exams. Among PCPs with access to US machines, the percentages of referred examinations were similar for sPOCUS (11.9%) and non-sPOCUS (11.3%) indications. However, some sPOCUS musculoskeletal ultrasounds were often referred (e.g. tendon/ligament/muscle injuries or cutaneous/subcutaneous tumour). CONCLUSION: Most Swiss PCPs had access to ultrasound equipment and performed a majority of both sPOCUS and non-sPOCUS scans themselves, often without or with incomplete training. This reflects the fact that POCUS was only recently introduced in Switzerland. There is a need for easily accessible POCUS training programs aimed at PCPs in Switzerland. Training courses for PCPs should focus on abdominal and musculoskeletal ultrasound, because these were the most common sites for scans, and because some sPOCUS musculoskeletal examinations showed a particularly high percentage of referral.

Artificial Intelligence-Based Evaluation of Carotid Artery Compressibility via Point-of-Care Ultrasound in Determining the Return of Spontaneous Circulation During Cardiopulmonary Resuscitation.

AIM: This study introduces RealCAC-Net, an artificial intelligence (AI) system, to quantify carotid artery compressibility (CAC) and determine the return of spontaneous circulation (ROSC) during cardiopulmonary resuscitation . METHODS: A prospective study based on data from a South Korean emergency department from 2022 to 2023 investigated carotid artery compressibility in adult patients with cardiac arrest using a novel AI model, RealCAC-Net. The data comprised 11,958 training images from 161 cases and 15,080 test images from 134 cases. RealCAC-Net processes images in three steps: TransUNet-based segmentation, the carotid artery compressibility measurement algorithm for improved segmentation and CAC calculation, and CAC-based classification from 0 (indicating a circular shape) to 1 (indicating high compression). The accuracy of the ROSC classification model was tested using metrics such as the dice similarity coefficient, intersection-over-union, precision, recall, and F1 score. RESULTS: RealCAC-Net, which applied the carotid artery compressibility measurement algorithm, performed better than the baseline model in cross-validation, with an average dice similarity coefficient of 0.90, an intersection-over-union of 0.84, and a classification accuracy of 0.96. The test set achieved a classification accuracy of 0.96 and an F1 score of 0.97, demonstrating its efficacy in accurately identifying ROSC in cardiac arrest situations. CONCLUSIONS: RealCAC-Net enabled precise CAC quantification for ROSC determination during cardiopulmonary resuscitation. Future research should integrate this AI-enhanced ultrasound approach to revolutionize emergency care.

Point-of-care isothermal nucleic acid amplification tests: progress and bottlenecks for extraction-free sample collection and preparation.

INTRODUCTION: Suitable sample collection and preparation methods are essential to enable nucleic acid amplification testing at the point of care (POC). Strategies that allow direct isothermal nucleic acid amplification testing (iNAAT) of crude sample lysate without the need for nucleic acid extraction minimize time to result as well as the need for operator expertise and costly infrastructure. AREAS COVERED: The authors review research to understand how sample matrix and preparation affect the design and performance of POC iNAATs. They focus on approaches where samples are directly combined with liquid reagents for preparation and amplification via iNAAT strategies. They review factors related to the type and method of sample collection, storage buffers, and lysis strategies. Finally, they discuss RNA targets and relevant regulatory considerations. EXPERT OPINION: Limitations in sample preparation methods are a significant technical barrier preventing implementation of nucleic acid testing at the POC. The authors propose a framework for co-designing sample preparation and amplification steps for optimal performance with an extraction-free paradigm by considering a sample matrix and lytic strategy prior to an amplification assay and readout. In the next 5 years, the authors anticipate increasing priority on the co-design of sample preparation and iNAATs.

The cost-effectiveness of integrating simplified HCV testing into HIV pre-exposure prophylaxis (PrEP) and treatment services among men who have sex with men in Taiwan.

Background: Simplified hepatitis C virus (HCV) testing integrated into existing HIV services has the potential to improve HCV diagnoses and treatment. We evaluated the cost-effectiveness of integrating different simplified HCV testing strategies into existing HIV pre-exposure prophylaxis (PrEP) and treatment services among men who have sex with men (MSM) in Taiwan. Methods: Mathematical modeling was used to assess the cost-effectiveness of integrating simplified HCV tests (point-of-care antibody, reflex RNA, or immediate point-of-care RNA) with HCV treatment into existing HIV prevention and care for MSM from a healthcare perspective. The impact of increasing PrEP and HIV treatment coverage among MSM in combination with these HCV testing strategies was also considered. We reported lifetime costs (2022 US dollars) and quality-adjusted life years (QALYs) and calculated incremental cost-effectiveness ratios (ICERs) with a 3% annual discounting rate. Findings: Point-of-care HCV antibody and reflex RNA testing are cost-effective compared to current HCV testing in all PrEP and HIV treatment coverage scenarios (ICERs <$32,811/QALY gained). Immediate point-of-care RNA testing would be only cost-effective compared to the current HCV testing if coverage of HIV services remained unchanged. Point-of-care antibody testing in an unchanged HIV services coverage scenario and all simplified HCV testing strategies in scenarios that increased both HIV PrEP and treatment coverage form an efficient frontier, indicating best value for money strategies. Interpretation: Our findings support the integration of simplified HCV testing and people-centered services for MSM and highlight the economic benefits of integrating simplified HCV testing into existing services for MSM alongside HIV PrEP and treatment. Funding: This study was made possible as part of a research-funded PhD being undertaken by HJW under the UNSW Sydney Scientia scholarship and was associated with the Rapid Point of Care Research Consortium for infectious disease in the Asia Pacific (RAPID), which is funded by an NHMRC Centre for Research Excellence. JG is supported by a National Health and Medical Research Council Investigator Grant (1176131).

The utilisation of emergency point-of-care ultrasound in a tertiary hospital emergency department in East London, South Africa.

Introduction: Emergency departments are the primary entry point for emergencies in the public healthcare system. Resource constraints burden a large proportion of the public hospital emergency departments, which includes limited access to radiological services. Emergency point-of-care ultrasound provides a tool capable of bridging this gap. The Eastern Cape is yet to describe the utilisation of emergency point-of-care ultrasound in any of its emergency departments. Methods: Frere Hospital initiated a clinical audit to assess the utilisation of emergency point-of-care ultrasound in its emergency department in 2022. This study was a retrospective review of the audit between 01 November 2022 until 28 February 2023. Data from the handwritten register regarding patient's presenting complaints and provisional diagnoses was also captured during the study period to draw comparisons between burden of disease and use of emergency point-of-care ultrasound. Results: A total of 9501 patients attended Frere Hospital's emergency department over the study period with 492 emergency point-of-care ultrasounds performed (overall utilisation rate 5.2 %). The five credentialed emergency point-of-care ultrasound providers performed the majority (n = 360, 73.2 %) of the applications, compared to 132 (26.8 %) performed by the seven non-credentialed providers. The extended focused abdominal sonography in trauma (eFAST) was the most frequently performed application (n = 140, 28.5 %). Conclusion: Emergency point-of-care ultrasound is underutilised in Frere Hospital's emergency department. The varied casemix requires upskilling of clinicians in emergency point-of-care ultrasound to suit the burden of disease experienced in the department. Ongoing emergency point-of-care ultrasound training, credentialing and research is important to ensure appropriate and quality emergency point-of-care ultrasound utilisation.