Causative Activities and Prognostic Factors of Open-Globe Injury: A Registry-Based City-Wide Multicentre Study.

PURPOSE: Traumatic globe injury is classified into closed-globe and open-globe injury (OGI); OGI leads to a worse prognosis. We aimed to identify causative activities and prognostic factors of OGI in a metropolitan city in South Korea. METHODS: This retrospective observational study used a prospective eye-injury registry conducted in Daegu, South Korea, between 1 August 2016 and 31 July 2021. We identified epidemiology and visual outcomes of OGI at four tertiary hospitals. Those with the best visual acuity lower than counting fingers at the 6-month follow-up were considered to have poor visual outcome. RESULTS: Of 9,208 patients with eye injuries, 282 had OGI. Most OGI patients were male (261, 92.6%), with the largest proportion in their 50s (76, 27.0%). The most frequent causative activity was mowing (59, 20.9%), and poor visual outcome was most seen in assault (7, 87.5%) and sports activity (9, 81.8%). Hammering, metal work, and sports activity were prevalent in those under 30, and mowing was most prevalent in those in their 50s (16, 21.1%) and 60s (29, 40.3%). In the multivariable logistic regression analysis, OGI related to traffic accident and sports activity were presented poor prognosis (adjusted odds ratio [aOR] 13.259, 95% confidence interval [CI] 1.202-146.205 for traffic accident; aOR 6.801, 95% CI 1.064-43.487 for sports activity). CONCLUSION: We need to develop advanced vehicle safety equipment, implement public education promoting seat belt usage and hazards of OGI, establish eye protection standards for key causal activities, and provide eye protection equipment for sports activities and mowing.

Vitamin D deficiency as a risk factor for sudden cardiac arrest: A multicenter case-control study.

BACKGROUND AND AIMS: Vitamin D is known to influence the risk of cardiovascular disease, which is a recognized risk factor for sudden cardiac arrest (SCA). However, the relationship between vitamin D and SCA is not well understood. Therefore, this study aims to investigate the association between vitamin D and SCA in out-of-hospital cardiac arrest (OHCA) patients compared to healthy controls. METHODS AND RESULTS: Using the Phase II Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance (CAPTURES II) registry, a 1:1 propensity score-matched case-control study was conducted between 2017 and 2020. Serum 25-hydroxyvitamin D (vitamin D) levels in patients with OHCA (454 cases) and healthy controls (454 cases) were compared after matching for age, sex, cardiovascular risk factors, and lifestyle behaviors. The mean vitamin D levels were 14.5 ± 7.6 and 21.3 ± 8.3 ng/mL among SCA cases and controls, respectively. Logistic regression analysis was used adjusting for cardiovascular risk factors, lifestyle behaviors, corrected serum calcium levels, and estimated glomerular filtration rate (eGRF). The adjusted odds ratio (aOR) for vitamin D was 0.89 (95% confidence interval [CI] 0.87-0.91). The dose-response relationship demonstrated that vitamin D deficiency was associated with SCA incidence (severe deficiency, aOR 10.87, 95% CI 4.82-24.54; moderate deficiency, aOR 2.24, 95% CI 1.20-4.20). CONCLUSION: Vitamin D deficiency was independently and strongly associated with an increased risk of SCA, irrespective of cardiovascular and lifestyle factors, corrected calcium levels, and eGFR.

Comparison of modal and zonal wavefront measurements of refractive extended depth of focus intraocular lenses.

Extended depth-of-focus (EDoF) intraocular lenses (IOLs) are typically evaluated using commercially available aberrometers. Given the intricate optical design of these IOLs, employing an appropriate wavefront reconstruction method with a sufficient sampling resolution of the aberrometer is crucial. A high-resolution Shack-Hartmann wavefront sensor was developed by magnifying the pupil aperture by a factor of five onto a lenslet array (pitch: 133 µm) and utilizing a full-frame CMOS sensor (24 by 36 mm), resulting in a 26.6 µm sampling resolution. Zonal wavefront reconstruction was used and compared with Zernike-based modal wavefront reconstruction to retain detailed local slope irregularities. Four refractive EDoF IOLs with a power of 20D were examined, and the wavefront difference between the zonal and modal methods, expressed as the root mean squared error (RMSE), remained significant for two of the IOLs up to the 16th-order Zernike spherical aberrations (SAs). Conversely, a negligibly small RMSE was observed for the other two IOLs, as long as the Zernike SAs were higher than the 6th order. The raytracing simulation results from the zonal wavefronts exhibited a stronger correlation with the results of recent optical bench studies than those from the modal wavefronts. The study suggests that certain recent refractive EDoF IOLs possess a complex optical profile that cannot be adequately characterized by limited orders of SAs.

Inappropriate use of intravenous epinephrine leading to atrial fibrillation during prehospital anaphylaxis treatment: A case report.

In a prehospital setting, the narrow therapeutic window of epinephrine necessitates its cautious administration for anaphylaxis. In this case, a 46-year-old man presented severe anaphylactic symptoms. Following standard protocol, the emergency medical technician (EMT) administered intramuscular epinephrine; however, symptoms persisted. Under the oversight of the emergency medical service (EMS) medical director, an additional intravenous bolus of epinephrine was administered, unfortunately leading to atrial fibrillation. This case underscores the potential risks of intravenous epinephrine, which isn't typically recommended for anaphylaxis without continuous monitoring. Since 2019, South Korea has initiated a pilot program to expand the EMT's scope of practice, which gives them the authority to administer epinephrine for anaphylaxis. The ultimate decision regarding epinephrine use for anaphylaxis, emphasizing patient safety, rests with the EMS medical director. Proper training for EMTs, coupled with the EMS medical director's comprehensive knowledge and meticulous protocol adherence, can ensure patient safety and optimal outcomes.

Prehospital factors associated with out-of-hospital cardiac arrest outcomes in a metropolitan city: a 4-year multicenter study.

BACKGROUND: Prehospital factors play a vital role in out-of-hospital cardiac arrest (OHCA) survivability, and they vary between countries and regions. We investigated the prehospital factors associated with OHCA outcomes in a single metropolitan city in the Republic of Korea. METHODS: This study included adult medical OHCA patients enrolled prospectively, using data from the citywide OHCA registry for patients registered between 2018 and 2021. The primary outcome was survival to hospital discharge. Multivariable logistic regression analysis was conducted to determine the factors associated with the study population's clinical outcomes, adjusting for covariates. We performed a sensitivity analysis for clinical outcomes only for patients without prehospital return of spontaneous circulation prior to emergency medical service departure from the scene. RESULTS: In multivariable logistic regression analysis, older age (odds ratio [OR] 0.96; 95% confidence interval [CI] 0.95-0.97), endotracheal intubation (adjusted odds ratio [aOR] 0.29; 95% [CIs] 0.17-0.51), supraglottic airway (aOR 0.29; 95% CI 0.17-0.51), prehospital mechanical chest compression device use (OR 0.13; 95% CI 0.08-0.18), and longer scene time interval (OR 0.96; 95% CI 0.93-1.00) were negatively associated with survival. Shockable rhythm (OR 24.54; 95% CI 12.99-42.00), pulseless electrical activity (OR 3.11; 95% CI 1.74-5.67), and witnessed cardiac arrest (OR 1.59; 95% CI 1.07-2.38) were positively associated with survival. In the sensitivity analysis, endotracheal intubation, supraglottic airway, prehospital mechanical chest compression device use, and longer scene time intervals were associated with significantly lower survival to hospital discharge. CONCLUSIONS: Regional resuscitation protocol should be revised based on the results of this study, and modifiable prehospital factors associated with lower survival of OHCA should be improved.

Exploring the Potential of a Thermionic LaB6 Virtual Source Mode Electron Gun for a High Angular Current Density and a Narrow Energy Distribution.

To date, lanthanum hexaboride (LaB6) thermionic electron sources have not been able fully to capitalize on their inherent potential, resulting in an ambiguous position within the application area. Although they exhibit higher brightness compared with a tungsten filament source, they still fall short of the performance of Schottky electron sources. This study aims to explore the capabilities of the LaB6 electron source under different operating conditions to bridge the gap, ultimately to realize its untapped potential. Simulations in virtual source mode indicated enhanced beam brightness and a reduced beam half-angle with an increase the extraction voltage, promising up to tenfold times higher beam brightness compared with the crossover mode. The energy distribution measured using a prelens retarding field energy analyzer revealed an energy distribution of 0.55 eV and a high angular current density of 33 mA/sr in the virtual source mode. Therefore, the virtual source mode of LaB6 can provide a narrow energy distribution akin to that of a ZrO/W Schottky electron gun (1600 K) while having an angular current density over 2,000 times higher. In addition, the stability of the virtual source mode is ±0.022%, while that of the crossover mode is ±0.138%.

Enhanced Scanning Electron Microscopy Using Auto-Optimized Image Restoration With Constrained Least Squares Filter for Nanoscience.

The growing demands of nanoscience require the continuous improvement of visualization methods. The imaging performance of scanning electron microscopy (SEM) is fundamentally limited by the point spread function of the electron beam and degrades because of noise. This paper proposes an auto-optimization algorithm based on deconvolution for the restoration of SEM images. This algorithm uses a constrained least squares filter and does not dependent on the user's experience or the availability of nondegraded images. The proposed algorithm improved the quality of the SEM images of 10-nm Au nanoparticles, and achieved balance among the sharpness, contrast-to-noise ratio (CNR), and image artifacts. For the SEM image of 100-nm pitched line patterns, the analysis of the spatial frequencies allowed the 2.5-fold improvement of the intensity of 4-nm information, and the noise floor decreased approximately 32 times. Along with the results obtained by the application of the proposed algorithm to images of tungsten disulfide (WS2) flakes, carbon nanotubes (CNTs), and HeLa cells, the evaluation results confirm that the proposed algorithm can enhance the SEM imaging of nanoscale features that lie close to the microscope's resolution limit.

Anti-heat shock protein 10 IgG in chronic spontaneous urticaria: Relation with miRNA-101-5p and platelet-activating factor.

BACKGROUND: Anti-heat shock protein (HSP) autoantibodies are detected in autoimmune diseases. We sought to ascertain whether anti-HSP10 IgG is present in patients with CSU and to elucidate the role of HSP10 in CSU pathogenesis. METHOD: Using a human proteome microarray, six potential autoantibodies had higher expression in 10 CSU samples compared with 10 normal controls (NCs). Among them, HSP10 IgG autoantibody was quantified by immune dot-blot assay in sera from 86 CSU patients and 44 NCs. The serum levels of HSP10 and microRNA-101-5p were measured in CSU patients and NCs. The effects of HSP10 and miR-101-5p on mast cell degranulation in response to IgE, compound 48/80, and platelet-activating factor (PAF) were investigated. RESULTS: CSU patients had higher IgG positivity to HSP10 (40.7% vs. 11.4%, p = .001), lower serum HSP10 levels (5.8 ± 3.6 vs. 12.2 ± 6.6 pg/mL, p < .001) than in NCs, and their urticaria severity was associated with anti-HSP10 IgG positivity, while HSP10 levels were related to urticaria control status. MiR-101-5p was increased in CSU patients. PAF enhanced IL4 production in PBMCs from CSU patients. IL-4 upregulated miR-101-5p and reduced HSP10 expression in keratinocytes. Transfection of miR-101-5p reduced HSP10 expression in keratinocytes. MiR-101-5p promoted PAF-induced mast cell degranulation, while HSP10 specifically prevented it. CONCLUSION: A new autoantibody, anti-HSP10 IgG was detected in CSU patients, which showed a significant correlation with UAS7 scores. A decreased serum HSP10 level was associated with upregulation of miR-101-5p due to increased IL-4 and PAF in CSU patients. Modulation of miR-101-5p and HSP10 may be a novel therapeutic approach for CSU.

Impact of emergency medical service with advanced life support training for adults with out-of-hospital cardiac arrest in the Republic of Korea: A retrospective multicenter study.

Prehospital advanced life support (ALS) has been offered in many countries for patients experiencing out-of-hospital cardiac arrest (OHCA); however, its effectiveness remains unclear. This study aimed to determine the impact of emergency medical service (EMS) with ALS training as a nationwide pilot project for adults with OHCA in the Republic of Korea. This retrospective multicenter observational study was conducted between July 2019 and December 2020 using the Korean Cardiac Arrest Research Consortium registry. The patients were categorized into an intervention group that received EMS with ALS training and a control group that did not receive EMS with ALS training. Conditional logistic regression analysis was performed using matched data to compare clinical outcomes between the two groups. Compared with the control group, the intervention group had a lower rate of supraglottic airway usage (60.5% vs. 75.6%) and a higher rate of undergoing endotracheal intubation (21.7% vs. 6.1%, P < 0.001). In addition, the intervention group was administered more intravenous epinephrine (59.8% vs. 14.2%, P < 0.001) and used mechanical chest compression devices more frequently in prehospital settings than the control group (59.0% vs. 23.8%, P < 0.001). Based on the results of multivariable conditional logistic regression analysis, survival to hospital discharge (odds ratio: 0.48, 95% confidence interval: 0.27-0.87) of the intervention group was significantly lower than that of the control group; however, good neurological outcome was not significantly different between the two groups. In this study, survival to hospital discharge was worse in patients with OHCA who received EMS with ALS training than in those who did not.

Comparison of incidence and outcome between occupational and non-occupational motorcycle injuries in Korea: A 7-years observational study.

Motorcycles are widely used in various workplaces. Motorcycle use for occupational purposes continues to increase owing to growing e-commerce. Here, we aimed to highlight the importance of occupational motorcycle injuries by analyzing their epidemiologic characteristics and outcomes. We analyzed retrospective data from the Emergency Department-based Injury In-depth Surveillance program from 2012 to 2018. Motor vehicle injuries involving riders aged ≥16 years were included. Patients were divided into occupational motorcycle and non-occupational motorcycle injury groups based on whether or not the injury occurred during work time. General characteristics, injury details, and clinical outcomes such as injury severity and in-hospital mortality were analyzed. Of the 37,194 study patients, 24.2% (8,991) experienced occupational motorcycle injuries. The number of injuries in both groups increased yearly, as did the proportion of occupational injuries among total injuries. In both the groups, patients aged 20-29 years had the highest proportion of injuries. Regarding collision pattern and injury counterpart, side-to-side collisions and injuries involving small four-wheel vehicles were the most frequent. Alcohol intake was significantly lower, while helmet usage was higher in the occupational motorcycle injury group. Moreover, patients with occupational motorcycle injuries had lower injury severity, admission rate, and in-hospital mortality. On multivariable logistic regression analysis, increasing age, time of the injury, alcohol intake, not using a helmet, and collision with a human or animal were associated with higher odds of severe injury. Patients with occupational injuries had higher helmet usage, lower injury severity, lower mortality, and lower admission rate than did patients with non-occupational injuries. Injury severity was associated with the time of injury, collision with other living objects, alcohol consumption, and helmet usage.

Influence of Zika virus 3'-end sequence and nonstructural protein evolution on the viral replication competence and virulence.

Zika virus (ZIKV) has been circulating in human networks over 70 years since its first appearance in Africa, yet little is known about whether the viral 3'-terminal sequence and nonstructural (NS) protein diverged genetically from ancient ZIKV have different effects on viral replication and virulence in currently prevailing Asian lineage ZIKV. Here we show, by a reverse genetics approach using an infectious cDNA clone for a consensus sequence (Con1) of ZIKV, which represents Asian ZIKV strains, and another clone derived from the MR766 strain isolated in Uganda, Africa in 1947, that the 3'-end sequence -UUUCU-3' homogeneously present in MR766 genome and the -GUCU-3' sequence strictly conserved in Asian ZIKV isolates are functionally equivalent in viral replication and gene expression. By gene swapping experiments using the two infectious cDNA clones, we show that the NS1-5 proteins of MR766 enhance replication competence of ZIKV Con1. The Con1, which was less virulent than MR766, acquired severe bilateral hindlimb paralysis when its NS1-5 genes were replaced by the counterparts of MR766 in type I interferon receptor (IFNAR1)-deficient A129 mice. Moreover, MR766 NS5 RNA-dependent RNA polymerase (RdRp) alone also rendered the Con1 virulent, despite there being no difference in RdRp activity between MR766 and Con1 NS5 proteins. By contrast, the Con1 derivatives expressing MR766 Nsps, like Con1, did not develop severe disease in wild-type mice treated with an IFNAR1 blocking antibody. Together, our findings uncover an unprecedented role for ZIKV NS proteins in determining viral pathogenicity in immunocompromised hosts.

High-Performance Compact Pre-Lens Retarding Field Energy Analyzer for Energy Distribution Measurements of an Electron Gun.

The energy distribution of an electron gun is one of the most important characteristics determining the performance of electron beam-based instruments, such as electron microscopes and electron energy loss spectroscopes. For accurate measurements of the energy distribution, this study presents a novel retarding field energy analyzer (RFEA) with the feature of an additional integrated pre-lens, which enables an adjustment of beam trajectory into the analyzer. The advantages of this analyzer are its compact size and simple electrode configuration. According to trajectory simulation theories, the optimum condition arises when the incident electron beam inside the RFEA is focused on the center of a retarding electrode. Comparing I­V curves depending on whether the pre-lens working or not, it is confirmed that the use of the pre-lens dramatically improves the energy resolution and efficiency of the signal acquisition process. The pre-lens RFEA was applied to characterize a Schottky electron gun under various temperatures and extraction voltages as operational conditions. When the tip temperature was increased by 50 K, we were able to measure an energy distribution broadening of 13.8 meV with the proposed pre-lens RFEA. The relative standard deviation of energy distribution was 0.7% for each working condition.

Neurologic outcomes of prehospital mechanical chest compression device use during transportation of out-of-hospital cardiac arrest patients: a multicenter observational study.

OBJECTIVE: High-quality cardiopulmonary resuscitation with chest compression is important for good neurologic outcomes during out-of-hospital cardiac arrest (OHCA). Several types of mechanical chest compression devices have recently been implemented in Korean emergency medical services. This study aimed to identify the effect of prehospital mechanical chest compression device use on the outcomes of OHCA patients. METHODS: We retrospectively analyzed data drawn from the regional cardiac arrest registry in Daegu, Korea. This registry prospectively collected data from January 2017 to December 2020. Patients aged 18 years or older who experienced cardiac arrest presumed to have a medical etiology were included. The exposure variable was the use of a prehospital mechanical device during transportation by emergency medical technicians. The outcomes measured were neurologic outcomes and survival to discharge. Logistic regression analysis was used. RESULTS: Among 3,230 OHCA patients, 1,111 (34.4%) and 2,119 (65.6%) were managed with manual chest compression and with a mechanical chest compression device, respectively. The mechanical chest compression group showed poorer neurologic outcomes than the manual chest compression group (adjusted odds ratio, 0.12; 95% confidence interval, 0.04-0.33) and decreased survival to discharge (adjusted odds ratio, 0.39; 95% confidence interval, 0.19-0.82) after adjustment for confounding variables. CONCLUSION: Prehospital mechanical chest compression device use in OHCA was associated with poorer neurologic outcomes and survival to discharge compared to manual chest compression.

High prevalence of depression and sleep-wake disorders among female emergency medicine residents in South Korea.

BACKGROUND: Depression and sleep-wake disorders are recognized as one of the major problems among emergency physicians. While depression is more common in females than in males, the associated factors linking depression and sleep-wake disorders in emergency physicians, particularly females, remain unknown. OBJECTIVE: To analyze the prevalence of depression and sleep-wake problems among emergency medicine (EM) residents in South Korea and to identify the gender differences and situations that adversely predispose female residents to mental health problems. METHODS: We conducted a cross-sectional analysis using the data collected from the 2019 National EM Residents Wellness Survey targeting all of 630 EM residents in South Korea. The survey included variables potentially influencing depression and sleep-wake problems, such as personal characteristics, work-related stress, and extrinsic environment. Information regarding medical conditions, depression, job stress, and sleep deprivation was obtained using the self-administered Patient Health Questionnaire (PHQ-9), the Apgar Wellness Score (AWS), and the Epworth Sleepiness Scale (ESS). We analyzed the data using IBM SPSS Statistics version 25 and MedCalc version 17. RESULTS: A total of 384 residents participated in the survey. Overall, 27.5% of the EM residents met the criteria for at least moderate depression and 36.9% of the EM residents had sleep-related problems. We found that difficulty in trading the shift schedule and frequent night shifts was associated with depression (p = .001, p = .005; respectively). Female residents demonstrated an increased risk of depression and sleepiness compared to their male counterparts (odds ratio [OR] 1.95, OR 1.81; respectively). In addition, logistic regression analysis revealed significant differences by gender in depression with regards to flexibility of trading shifts (p = .005), level of training in the emergency medical centre (p = .035), and frequent night shifts (p = .010). CONCLUSIONS: Approximately, one-third of EM residents report depression and sleep-wake problems, with female residents showing a higher risk than male residents. Several risk factors were identified, and future strategies should be aimed to address these issues to improve the training environment and overall wellbeing of EM residents.KEY MESSAGESThe prevalence of depression and sleep-related problems were, respectively, 1.95 and 1.81 times higher in female residents compared to their male colleagues.The associated risk factors for depression were flexibility of shift trade, level of training in the emergency medical centre, and frequency of night shifts.Improving the training environment and facilities, as well as offering more flexible duty trading options can provide potential opportunities to reduce the risk.

Real-world evidence for subcutaneous infliximab (CT-P13 SC) treatment in patients with psoriatic arthritis during the coronavirus disease (COVID-19) pandemic: A case series.

The COVID-19 pandemic highlighted the benefits of subcutaneous (SC) administration for healthcare systems. The first SC infliximab, CT-P13 SC, was safe and effective for the treatment of psoriatic arthritis. Observed patient preferences for continuing CT-P13 SC suggest that patients receiving IV infliximab should be offered a switch to CT-P13 SC.

Epidemiological Characteristics of Paediatric Eye Injuries in a Large Metropolitan City in South Korea: A Multicentre, Prospective Study.

PURPOSE: The aim of this study was to identify the epidemiological characteristics of paediatric eye injury in a large metropolitan city based on age group and sex. METHODS: This prospective, multicentre, observational study used data extracted from the eye injury registry for tertiary teaching hospitals in Daegu, South Korea, between August 2016 and July 2018. Children aged < 16 years were classified as infants, pre-schoolers, school children, and adolescents based on their age group. RESULTS: This study included 502 patients; most eye injuries occurred among boys (n = 349, 69.5%) and school children (n = 168, 33.5%). Unstructured play (n = 268, 53.4%) was the most common cause of eye injury, followed by sports (n = 69, 13.7%) and home activities (n = 52, 10.4%). Among adolescent boys, eye injuries were mostly caused by sports activities (n = 49, 37.7%), including soccer and basketball. Only 1 out of 69 children wore protective eyewear during sports activities. Eye injuries occurred most often in school (n = 63, 41.2%) during adolescence and at home (n = 270, 53.8%) in most other age groups. CONCLUSION: Eye injuries were more common in boys. Boys and girls had relatively higher proportion of eye injuries during sports and home activities, respectively. In infants to school children, eye injuries mainly occurred at home and by unstructured play, whereas in adolescents, they mostly occurred at school and during sports activities. To prevent eye injuries sustained during sports in adolescents, wearing personal protective equipment during high-risk exercise in schools or sports facilities is recommended.

Effective Response to a Regional Outbreak of COVID-19: Experience of a Tertiary Emergency Center.

OBJECTIVE: This study evaluates the usefulness, safety, and outcomes of operating a pretriage screening clinic and an expanded preemptive quarantine area in the emergency department (ED) during a regional coronavirus disease 2019 (COVID-19) outbreak. METHODS: A descriptive cross-sectional, retrospective study conducted in a single institution. General patient demographic data, initial vital sign, symptoms, and patient outcome was collected from January to March of 2020. Data were compared according to the implementation of a new protocol involving pretriage screening and risk stratification. Outcome was also analyzed according to quarantine areas, including conventional, negative pressured, cohort, or preemptive quarantine area. RESULTS: The pretriage clinic lowered the volume of low severity patients entering emergency department. Preemptive and cohort quarantine area provided more care to febrile patients compared with conventional quarantine area with longer length of hospital stay and lower mortality. After implementing the new protocol, emergency department in the study hospital was not closed again. CONCLUSIONS: In a regional outbreak of an epidemic, pretriage clinic safely screened infectious patients from entering ED. Expanded preemptive quarantine area increased surge capacity on quarantine area. An infectious disease protocol implementing 2 treatment areas may contribute to preserve and maintain ED function.

High-sensitivity microvolume UV absorption spectrometry for routine analysis of small-volume biological samples.

Substantial improvement of microvolume UV absorption spectrometry in sensitivity, robustness and ease of operation was achieved for routine biological applications. A unique microtubing-based absorption cell (208 µm internal diameter) featuring enhanced light transmission with a liquid core waveguide technique provided dramatically enhanced absorption sensitivity, proportional to the extended path length (50 mm, from the typical 1 mm), while robust measurement performance was attained by implementation of preventive measures against bubble trapping along the light path. For pBR322 plasmid DNA, absorbance at 260 nm was reliably measurable down to 0.1 ng/µl with repeatability typically 2-3% RSD. The detection limit was 0.03 ng/µl dsDNA, far lower than the current state-of-the-art âˆ¼1 ng/µl. Sample consumption for each measurement was 2.4 µl. Automated operation implemented for the first time in microvolume spectrophotometry facilitated the ease in handling with small-volume biological samples.

External validation of multimodal termination of resuscitation rules for out-of-hospital cardiac arrest patients in the COVID-19 era.

BACKGROUND: Futile resuscitation for out-of-hospital cardiac arrest (OHCA) patients in the coronavirus disease (COVID)-19 era can lead to risk of disease transmission and unnecessary transport. Various existing basic or advanced life support (BLS or ALS, respectively) rules for the termination of resuscitation (TOR) have been derived and validated in North America and Asian countries. This study aimed to evaluate the external validation of these rules in predicting the survival outcomes of OHCA patients in the COVID-19 era. METHODS: This was a multicenter observational study using the WinCOVID-19 Daegu registry data collected during February 18-March 31, 2020. The subjects were patients who showed cardiac arrest of presumed cardiac etiology. The outcomes of each rule were compared to the actual patient survival outcomes. The sensitivity, specificity, false positive value (FPV), and positive predictive value (PPV) of each TOR rule were evaluated. RESULTS: In total, 170 of the 184 OHCA patients were eligible and evaluated. TOR was recommended for 122 patients based on the international basic life support termination of resuscitation (BLS-TOR) rule, which showed 85% specificity, 74% sensitivity, 0.8% FPV, and 99% PPV for predicting unfavorable survival outcomes. When the traditional BLS-TOR rules and KoCARC TOR rule II were applied to our registry, one patient met the TOR criteria but survived at hospital discharge. With regard to the FPV (upper limit of 95% confidence interval < 5%), specificity (100%), and PPV (> 99%) criteria, only the KoCARC TOR rule I, which included a combination of three factors including not being witnessed by emergency medical technicians, presenting with an asystole at the scene, and not experiencing prehospital shock delivery or return of spontaneous circulation, was found to be superior to all other TOR rules. CONCLUSION: Among the previous nine BLS and ALS TOR rules, KoCARC TOR rule I was most suitable for predicting poor survival outcomes and showed improved diagnostic performance. Further research on variations in resources and treatment protocols among facilities, regions, and cultures will be useful in determining the feasibility of TOR rules for COVID-19 patients worldwide.